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Publisher: Elsevier   (Total: 3155 journals)

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Showing 1 - 200 of 3155 Journals sorted alphabetically
A Practical Logic of Cognitive Systems     Full-text available via subscription   (Followers: 9)
AASRI Procedia     Open Access   (Followers: 15)
Academic Pediatrics     Hybrid Journal   (Followers: 34, SJR: 1.655, CiteScore: 2)
Academic Radiology     Hybrid Journal   (Followers: 23, SJR: 1.015, CiteScore: 2)
Accident Analysis & Prevention     Partially Free   (Followers: 96, SJR: 1.462, CiteScore: 3)
Accounting Forum     Hybrid Journal   (Followers: 27, SJR: 0.932, CiteScore: 2)
Accounting, Organizations and Society     Hybrid Journal   (Followers: 38, SJR: 1.771, CiteScore: 3)
Achievements in the Life Sciences     Open Access   (Followers: 5)
Acta Anaesthesiologica Taiwanica     Open Access   (Followers: 7)
Acta Astronautica     Hybrid Journal   (Followers: 411, SJR: 0.758, CiteScore: 2)
Acta Automatica Sinica     Full-text available via subscription   (Followers: 2)
Acta Biomaterialia     Hybrid Journal   (Followers: 27, SJR: 1.967, CiteScore: 7)
Acta Colombiana de Cuidado Intensivo     Full-text available via subscription   (Followers: 2)
Acta de Investigación Psicológica     Open Access   (Followers: 3)
Acta Ecologica Sinica     Open Access   (Followers: 10, SJR: 0.18, CiteScore: 1)
Acta Haematologica Polonica     Free   (Followers: 1, SJR: 0.128, CiteScore: 0)
Acta Histochemica     Hybrid Journal   (Followers: 3, SJR: 0.661, CiteScore: 2)
Acta Materialia     Hybrid Journal   (Followers: 259, SJR: 3.263, CiteScore: 6)
Acta Mathematica Scientia     Full-text available via subscription   (Followers: 5, SJR: 0.504, CiteScore: 1)
Acta Mechanica Solida Sinica     Full-text available via subscription   (Followers: 9, SJR: 0.542, CiteScore: 1)
Acta Oecologica     Hybrid Journal   (Followers: 12, SJR: 0.834, CiteScore: 2)
Acta Otorrinolaringologica (English Edition)     Full-text available via subscription  
Acta Otorrinolaringológica Española     Full-text available via subscription   (Followers: 3, SJR: 0.307, CiteScore: 0)
Acta Pharmaceutica Sinica B     Open Access   (Followers: 1, SJR: 1.793, CiteScore: 6)
Acta Poética     Open Access   (Followers: 4, SJR: 0.101, CiteScore: 0)
Acta Psychologica     Hybrid Journal   (Followers: 28, SJR: 1.331, CiteScore: 2)
Acta Sociológica     Open Access   (Followers: 1)
Acta Tropica     Hybrid Journal   (Followers: 6, SJR: 1.052, CiteScore: 2)
Acta Urológica Portuguesa     Open Access  
Actas Dermo-Sifiliograficas     Full-text available via subscription   (Followers: 3, SJR: 0.374, CiteScore: 1)
Actas Dermo-Sifiliográficas (English Edition)     Full-text available via subscription   (Followers: 2)
Actas Urológicas Españolas     Full-text available via subscription   (Followers: 3, SJR: 0.344, CiteScore: 1)
Actas Urológicas Españolas (English Edition)     Full-text available via subscription   (Followers: 1)
Actualites Pharmaceutiques     Full-text available via subscription   (Followers: 6, SJR: 0.19, CiteScore: 0)
Actualites Pharmaceutiques Hospitalieres     Full-text available via subscription   (Followers: 3)
Acupuncture and Related Therapies     Hybrid Journal   (Followers: 6)
Acute Pain     Full-text available via subscription   (Followers: 14, SJR: 2.671, CiteScore: 5)
Ad Hoc Networks     Hybrid Journal   (Followers: 11, SJR: 0.53, CiteScore: 4)
Addictive Behaviors     Hybrid Journal   (Followers: 17, SJR: 1.29, CiteScore: 3)
Addictive Behaviors Reports     Open Access   (Followers: 8, SJR: 0.755, CiteScore: 2)
Additive Manufacturing     Hybrid Journal   (Followers: 10, SJR: 2.611, CiteScore: 8)
Additives for Polymers     Full-text available via subscription   (Followers: 22)
Advanced Drug Delivery Reviews     Hybrid Journal   (Followers: 154, SJR: 4.09, CiteScore: 13)
Advanced Engineering Informatics     Hybrid Journal   (Followers: 11, SJR: 1.167, CiteScore: 4)
Advanced Powder Technology     Hybrid Journal   (Followers: 17, SJR: 0.694, CiteScore: 3)
Advances in Accounting     Hybrid Journal   (Followers: 8, SJR: 0.277, CiteScore: 1)
Advances in Agronomy     Full-text available via subscription   (Followers: 14, SJR: 2.384, CiteScore: 5)
Advances in Anesthesia     Full-text available via subscription   (Followers: 28, SJR: 0.126, CiteScore: 0)
Advances in Antiviral Drug Design     Full-text available via subscription   (Followers: 2)
Advances in Applied Mathematics     Full-text available via subscription   (Followers: 10, SJR: 0.992, CiteScore: 1)
Advances in Applied Mechanics     Full-text available via subscription   (Followers: 11, SJR: 1.551, CiteScore: 4)
Advances in Applied Microbiology     Full-text available via subscription   (Followers: 24, SJR: 2.089, CiteScore: 5)
Advances In Atomic, Molecular, and Optical Physics     Full-text available via subscription   (Followers: 14, SJR: 0.572, CiteScore: 2)
Advances in Biological Regulation     Hybrid Journal   (Followers: 4, SJR: 2.61, CiteScore: 7)
Advances in Botanical Research     Full-text available via subscription   (Followers: 2, SJR: 0.686, CiteScore: 2)
Advances in Cancer Research     Full-text available via subscription   (Followers: 33, SJR: 3.043, CiteScore: 6)
Advances in Carbohydrate Chemistry and Biochemistry     Full-text available via subscription   (Followers: 9, SJR: 1.453, CiteScore: 2)
Advances in Catalysis     Full-text available via subscription   (Followers: 5, SJR: 1.992, CiteScore: 5)
Advances in Cell Aging and Gerontology     Full-text available via subscription   (Followers: 4)
Advances in Cellular and Molecular Biology of Membranes and Organelles     Full-text available via subscription   (Followers: 12)
Advances in Chemical Engineering     Full-text available via subscription   (Followers: 27, SJR: 0.156, CiteScore: 1)
Advances in Child Development and Behavior     Full-text available via subscription   (Followers: 10, SJR: 0.713, CiteScore: 1)
Advances in Chronic Kidney Disease     Full-text available via subscription   (Followers: 10, SJR: 1.316, CiteScore: 2)
Advances in Clinical Chemistry     Full-text available via subscription   (Followers: 29, SJR: 1.562, CiteScore: 3)
Advances in Colloid and Interface Science     Full-text available via subscription   (Followers: 19, SJR: 1.977, CiteScore: 8)
Advances in Computers     Full-text available via subscription   (Followers: 14, SJR: 0.205, CiteScore: 1)
Advances in Dermatology     Full-text available via subscription   (Followers: 14)
Advances in Developmental Biology     Full-text available via subscription   (Followers: 12)
Advances in Digestive Medicine     Open Access   (Followers: 9)
Advances in DNA Sequence-Specific Agents     Full-text available via subscription   (Followers: 5)
Advances in Drug Research     Full-text available via subscription   (Followers: 25)
Advances in Ecological Research     Full-text available via subscription   (Followers: 44, SJR: 2.524, CiteScore: 4)
Advances in Engineering Software     Hybrid Journal   (Followers: 28, SJR: 1.159, CiteScore: 4)
Advances in Experimental Biology     Full-text available via subscription   (Followers: 8)
Advances in Experimental Social Psychology     Full-text available via subscription   (Followers: 46, SJR: 5.39, CiteScore: 8)
Advances in Exploration Geophysics     Full-text available via subscription   (Followers: 1)
Advances in Fluorine Science     Full-text available via subscription   (Followers: 9)
Advances in Food and Nutrition Research     Full-text available via subscription   (Followers: 58, SJR: 0.591, CiteScore: 2)
Advances in Fuel Cells     Full-text available via subscription   (Followers: 16)
Advances in Genetics     Full-text available via subscription   (Followers: 16, SJR: 1.354, CiteScore: 4)
Advances in Genome Biology     Full-text available via subscription   (Followers: 8, SJR: 12.74, CiteScore: 13)
Advances in Geophysics     Full-text available via subscription   (Followers: 6, SJR: 1.193, CiteScore: 3)
Advances in Heat Transfer     Full-text available via subscription   (Followers: 23, SJR: 0.368, CiteScore: 1)
Advances in Heterocyclic Chemistry     Full-text available via subscription   (Followers: 12, SJR: 0.749, CiteScore: 3)
Advances in Human Factors/Ergonomics     Full-text available via subscription   (Followers: 22)
Advances in Imaging and Electron Physics     Full-text available via subscription   (Followers: 2, SJR: 0.193, CiteScore: 0)
Advances in Immunology     Full-text available via subscription   (Followers: 35, SJR: 4.433, CiteScore: 6)
Advances in Inorganic Chemistry     Full-text available via subscription   (Followers: 8, SJR: 1.163, CiteScore: 2)
Advances in Insect Physiology     Full-text available via subscription   (Followers: 2, SJR: 1.938, CiteScore: 3)
Advances in Integrative Medicine     Hybrid Journal   (Followers: 6, SJR: 0.176, CiteScore: 0)
Advances in Intl. Accounting     Full-text available via subscription   (Followers: 3)
Advances in Life Course Research     Hybrid Journal   (Followers: 8, SJR: 0.682, CiteScore: 2)
Advances in Lipobiology     Full-text available via subscription   (Followers: 1)
Advances in Magnetic and Optical Resonance     Full-text available via subscription   (Followers: 8)
Advances in Marine Biology     Full-text available via subscription   (Followers: 18, SJR: 0.88, CiteScore: 2)
Advances in Mathematics     Full-text available via subscription   (Followers: 11, SJR: 3.027, CiteScore: 2)
Advances in Medical Sciences     Hybrid Journal   (Followers: 6, SJR: 0.694, CiteScore: 2)
Advances in Medicinal Chemistry     Full-text available via subscription   (Followers: 5)
Advances in Microbial Physiology     Full-text available via subscription   (Followers: 4, SJR: 1.158, CiteScore: 3)
Advances in Molecular and Cell Biology     Full-text available via subscription   (Followers: 23)
Advances in Molecular and Cellular Endocrinology     Full-text available via subscription   (Followers: 8)
Advances in Molecular Toxicology     Full-text available via subscription   (Followers: 7, SJR: 0.182, CiteScore: 0)
Advances in Nanoporous Materials     Full-text available via subscription   (Followers: 3)
Advances in Oncobiology     Full-text available via subscription   (Followers: 1)
Advances in Organ Biology     Full-text available via subscription   (Followers: 1)
Advances in Organometallic Chemistry     Full-text available via subscription   (Followers: 17, SJR: 1.875, CiteScore: 4)
Advances in Parallel Computing     Full-text available via subscription   (Followers: 7, SJR: 0.174, CiteScore: 0)
Advances in Parasitology     Full-text available via subscription   (Followers: 5, SJR: 1.579, CiteScore: 4)
Advances in Pediatrics     Full-text available via subscription   (Followers: 24, SJR: 0.461, CiteScore: 1)
Advances in Pharmaceutical Sciences     Full-text available via subscription   (Followers: 12)
Advances in Pharmacology     Full-text available via subscription   (Followers: 16, SJR: 1.536, CiteScore: 3)
Advances in Physical Organic Chemistry     Full-text available via subscription   (Followers: 8, SJR: 0.574, CiteScore: 1)
Advances in Phytomedicine     Full-text available via subscription  
Advances in Planar Lipid Bilayers and Liposomes     Full-text available via subscription   (Followers: 3, SJR: 0.109, CiteScore: 1)
Advances in Plant Biochemistry and Molecular Biology     Full-text available via subscription   (Followers: 10)
Advances in Plant Pathology     Full-text available via subscription   (Followers: 5)
Advances in Porous Media     Full-text available via subscription   (Followers: 5)
Advances in Protein Chemistry     Full-text available via subscription   (Followers: 18)
Advances in Protein Chemistry and Structural Biology     Full-text available via subscription   (Followers: 20, SJR: 0.791, CiteScore: 2)
Advances in Psychology     Full-text available via subscription   (Followers: 64)
Advances in Quantum Chemistry     Full-text available via subscription   (Followers: 6, SJR: 0.371, CiteScore: 1)
Advances in Radiation Oncology     Open Access   (SJR: 0.263, CiteScore: 1)
Advances in Small Animal Medicine and Surgery     Hybrid Journal   (Followers: 3, SJR: 0.101, CiteScore: 0)
Advances in Space Biology and Medicine     Full-text available via subscription   (Followers: 6)
Advances in Space Research     Full-text available via subscription   (Followers: 400, SJR: 0.569, CiteScore: 2)
Advances in Structural Biology     Full-text available via subscription   (Followers: 5)
Advances in Surgery     Full-text available via subscription   (Followers: 11, SJR: 0.555, CiteScore: 2)
Advances in the Study of Behavior     Full-text available via subscription   (Followers: 34, SJR: 2.208, CiteScore: 4)
Advances in Veterinary Medicine     Full-text available via subscription   (Followers: 17)
Advances in Veterinary Science and Comparative Medicine     Full-text available via subscription   (Followers: 13)
Advances in Virus Research     Full-text available via subscription   (Followers: 5, SJR: 2.262, CiteScore: 5)
Advances in Water Resources     Hybrid Journal   (Followers: 46, SJR: 1.551, CiteScore: 3)
Aeolian Research     Hybrid Journal   (Followers: 6, SJR: 1.117, CiteScore: 3)
Aerospace Science and Technology     Hybrid Journal   (Followers: 347, SJR: 0.796, CiteScore: 3)
AEU - Intl. J. of Electronics and Communications     Hybrid Journal   (Followers: 8, SJR: 0.42, CiteScore: 2)
African J. of Emergency Medicine     Open Access   (Followers: 6, SJR: 0.296, CiteScore: 0)
Ageing Research Reviews     Hybrid Journal   (Followers: 11, SJR: 3.671, CiteScore: 9)
Aggression and Violent Behavior     Hybrid Journal   (Followers: 456, SJR: 1.238, CiteScore: 3)
Agri Gene     Hybrid Journal   (Followers: 1, SJR: 0.13, CiteScore: 0)
Agricultural and Forest Meteorology     Hybrid Journal   (Followers: 17, SJR: 1.818, CiteScore: 5)
Agricultural Systems     Hybrid Journal   (Followers: 31, SJR: 1.156, CiteScore: 4)
Agricultural Water Management     Hybrid Journal   (Followers: 41, SJR: 1.272, CiteScore: 3)
Agriculture and Agricultural Science Procedia     Open Access   (Followers: 4)
Agriculture and Natural Resources     Open Access   (Followers: 3)
Agriculture, Ecosystems & Environment     Hybrid Journal   (Followers: 57, SJR: 1.747, CiteScore: 4)
Ain Shams Engineering J.     Open Access   (Followers: 5, SJR: 0.589, CiteScore: 3)
Air Medical J.     Hybrid Journal   (Followers: 6, SJR: 0.26, CiteScore: 0)
AKCE Intl. J. of Graphs and Combinatorics     Open Access   (SJR: 0.19, CiteScore: 0)
Alcohol     Hybrid Journal   (Followers: 11, SJR: 1.153, CiteScore: 3)
Alcoholism and Drug Addiction     Open Access   (Followers: 10)
Alergologia Polska : Polish J. of Allergology     Full-text available via subscription   (Followers: 1)
Alexandria Engineering J.     Open Access   (Followers: 1, SJR: 0.604, CiteScore: 3)
Alexandria J. of Medicine     Open Access   (Followers: 1, SJR: 0.191, CiteScore: 1)
Algal Research     Partially Free   (Followers: 11, SJR: 1.142, CiteScore: 4)
Alkaloids: Chemical and Biological Perspectives     Full-text available via subscription   (Followers: 2)
Allergologia et Immunopathologia     Full-text available via subscription   (Followers: 1, SJR: 0.504, CiteScore: 1)
Allergology Intl.     Open Access   (Followers: 5, SJR: 1.148, CiteScore: 2)
Alpha Omegan     Full-text available via subscription   (SJR: 3.521, CiteScore: 6)
ALTER - European J. of Disability Research / Revue Européenne de Recherche sur le Handicap     Full-text available via subscription   (Followers: 9, SJR: 0.201, CiteScore: 1)
Alzheimer's & Dementia     Hybrid Journal   (Followers: 51, SJR: 4.66, CiteScore: 10)
Alzheimer's & Dementia: Diagnosis, Assessment & Disease Monitoring     Open Access   (Followers: 4, SJR: 1.796, CiteScore: 4)
Alzheimer's & Dementia: Translational Research & Clinical Interventions     Open Access   (Followers: 4, SJR: 1.108, CiteScore: 3)
Ambulatory Pediatrics     Hybrid Journal   (Followers: 6)
American Heart J.     Hybrid Journal   (Followers: 50, SJR: 3.267, CiteScore: 4)
American J. of Cardiology     Hybrid Journal   (Followers: 54, SJR: 1.93, CiteScore: 3)
American J. of Emergency Medicine     Hybrid Journal   (Followers: 45, SJR: 0.604, CiteScore: 1)
American J. of Geriatric Pharmacotherapy     Full-text available via subscription   (Followers: 10)
American J. of Geriatric Psychiatry     Hybrid Journal   (Followers: 14, SJR: 1.524, CiteScore: 3)
American J. of Human Genetics     Hybrid Journal   (Followers: 34, SJR: 7.45, CiteScore: 8)
American J. of Infection Control     Hybrid Journal   (Followers: 29, SJR: 1.062, CiteScore: 2)
American J. of Kidney Diseases     Hybrid Journal   (Followers: 35, SJR: 2.973, CiteScore: 4)
American J. of Medicine     Hybrid Journal   (Followers: 47)
American J. of Medicine Supplements     Full-text available via subscription   (Followers: 3, SJR: 1.967, CiteScore: 2)
American J. of Obstetrics and Gynecology     Hybrid Journal   (Followers: 216, SJR: 2.7, CiteScore: 4)
American J. of Ophthalmology     Hybrid Journal   (Followers: 66, SJR: 3.184, CiteScore: 4)
American J. of Ophthalmology Case Reports     Open Access   (Followers: 5, SJR: 0.265, CiteScore: 0)
American J. of Orthodontics and Dentofacial Orthopedics     Full-text available via subscription   (Followers: 6, SJR: 1.289, CiteScore: 1)
American J. of Otolaryngology     Hybrid Journal   (Followers: 25, SJR: 0.59, CiteScore: 1)
American J. of Pathology     Hybrid Journal   (Followers: 28, SJR: 2.139, CiteScore: 4)
American J. of Preventive Medicine     Hybrid Journal   (Followers: 28, SJR: 2.164, CiteScore: 4)
American J. of Surgery     Hybrid Journal   (Followers: 38, SJR: 1.141, CiteScore: 2)
American J. of the Medical Sciences     Hybrid Journal   (Followers: 12, SJR: 0.767, CiteScore: 1)
Ampersand : An Intl. J. of General and Applied Linguistics     Open Access   (Followers: 7)
Anaerobe     Hybrid Journal   (Followers: 4, SJR: 1.144, CiteScore: 3)
Anaesthesia & Intensive Care Medicine     Full-text available via subscription   (Followers: 63, SJR: 0.138, CiteScore: 0)
Anaesthesia Critical Care & Pain Medicine     Full-text available via subscription   (Followers: 18, SJR: 0.411, CiteScore: 1)
Anales de Cirugia Vascular     Full-text available via subscription  
Anales de Pediatría     Full-text available via subscription   (Followers: 3, SJR: 0.277, CiteScore: 0)
Anales de Pediatría (English Edition)     Full-text available via subscription  
Anales de Pediatría Continuada     Full-text available via subscription  
Analytic Methods in Accident Research     Hybrid Journal   (Followers: 5, SJR: 4.849, CiteScore: 10)
Analytica Chimica Acta     Hybrid Journal   (Followers: 42, SJR: 1.512, CiteScore: 5)
Analytical Biochemistry     Hybrid Journal   (Followers: 180, SJR: 0.633, CiteScore: 2)
Analytical Chemistry Research     Open Access   (Followers: 12, SJR: 0.411, CiteScore: 2)
Analytical Spectroscopy Library     Full-text available via subscription   (Followers: 11)
Anesthésie & Réanimation     Full-text available via subscription   (Followers: 2)
Anesthesiology Clinics     Full-text available via subscription   (Followers: 23, SJR: 0.683, CiteScore: 2)
Angiología     Full-text available via subscription   (SJR: 0.121, CiteScore: 0)
Angiologia e Cirurgia Vascular     Open Access   (Followers: 1, SJR: 0.111, CiteScore: 0)
Animal Behaviour     Hybrid Journal   (Followers: 201, SJR: 1.58, CiteScore: 3)

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Journal Cover
Academic Radiology
Journal Prestige (SJR): 1.015
Citation Impact (citeScore): 2
Number of Followers: 23  
 
  Hybrid Journal Hybrid journal (It can contain Open Access articles)
ISSN (Print) 1076-6332
Published by Elsevier Homepage  [3155 journals]
  • Perceptual and Interpretive Error in Diagnostic Radiology—Causes and
           Potential Solutions
    • Abstract: Publication date: Available online 14 December 2018Source: Academic RadiologyAuthor(s): Andrew J. Degnan, Emily H. Ghobadi, Peter Hardy, Elizabeth Krupinski, Elena P. Scali, Lindsay Stratchko, Adam Ulano, Eric Walker, Ashish P. Wasnik, William F. AuffermannInterpretation of increasingly complex imaging studies involves multiple intricate tasks requiring visual evaluation, cognitive processing, and decision-making. At each stage of this process, there are opportunities for error due to human factors including perceptual and ergonomic conditions. Investigation into the root causes of interpretive error in radiology first began over a century ago. In more recent work, there has been increasing recognition of the limits of human image perception and other human factors and greater acknowledgement of the role of the radiologist's environment in increasing the risk of error. This article reviews the state of research on perceptual and interpretive error in radiology. This article focuses on avenues for further error examination, and strategies for mitigating these errors are discussed. The relationship between artificial intelligence and interpretive error is also considered.
       
  • Lung Cancer Screening with Low-Dose CT: Baseline Screening Results in
           Shanghai
    • Abstract: Publication date: Available online 14 December 2018Source: Academic RadiologyAuthor(s): Li Fan, Yun Wang, Ying Zhou, Qiong Li, Wenjie Yang, Shengping Wang, Fei Shan, Xingwei Zhang, Jingyun Shi, Wufei Chen, Shi-Yuan LiuObjectiveTo report the initial baseline lung cancer screening results with low dose computed tomography (LDCT) in a multicenter study in Shanghai.MethodsA total of 14,506 subjects underwent LDCT lung cancer screening and completed questionnaires consisting of 13 risk factors for lung cancer in the prospective study. The positive result was defined as any size and density nodule. The nodules were classified into calcified, solid, part-solid, and nonsolid nodules. The positive rate and incidental detection rate of lung cancer and stage I lung cancer were calculated. The proportion of lung nodule and lung cancer with different density and size was analyzed.ResultsThe positive rate and incidental detection rate of lung cancer was 29.89% and 1.23%, respectively. The incidental detection rate of stage I lung cancer was 0.97%. The proportion of lung cancer in lung nodules and stage I in lung cancer was 3.48% and 81.09%, respectively. The ratio of nonsolid nodule, part-solid nodule, and solid nodule in lung cancer was 52.94%, 31.93%, and 15.13%, respectively. 74.88% lung nodules were less than 5 mm and 94.12% lung cancers were larger than 5mm in size.ConclusionThe baseline LDCT lung cancer screening showed subsolid nodules accounted for the majority of lung cancer, and 5 mm in size would be recommended as the positive result threshold.
       
  • Performance of Diffusion Kurtosis Imaging Versus Diffusion Tensor Imaging
           in Discriminating Between Benign Tissue, Low and High Gleason Grade
           Prostate Cancer
    • Abstract: Publication date: Available online 11 December 2018Source: Academic RadiologyAuthor(s): Maria Giovanna Di Trani, Marco Nezzo, Alessandra S. Caporale, Riccardo De Feo, Roberto Miano, Alessandro Mauriello, Pierluigi Bove, Guglielmo Manenti, Silvia CapuaniRationale and ObjectivesTo investigate the performance of diffusion kurtosis imaging (DKI) and diffusion tensor imaging (DTI) in discriminating benign tissue, low- and high-grade prostate adenocarcinoma (PCa).Materials and MethodsForty-eight patients with biopsy-proven PCa of different Gleason grade (GG), who provided written informed consent, were enrolled. All subjects underwent 3T DWI examinations by using b values 0, 500, 1000, 1500, 2000, and 2500 s/mm2 and six gradient directions. Mean diffusivity, fractional anisotropy (FA), apparent kurtosis (K), apparent kurtosis-derived diffusivity (D), and proxy fractional kurtosis anisotropy (KFA) maps were obtained. Regions of interest were selected in PCa, in the contralateral benign zone, and in the peritumoral area. Histogram analysis was performed by measuring mean, 10th, 25th, and 90th (p90) percentile of the whole-lesion volume. Kruskal–Wallis test with Bonferroni correction was used to assess significant differences between different regions of interest. The correlation between diffusion metrics and GG and between DKI and DTI parameters was evaluated with Pearson's test. ROC curve analysis was carried out to analyze the ability of histogram variables to differentiate low- and high-GG PCa.ResultsAll metrics significantly discriminated PCa from benign and from peritumoral tissue (except for K, KFAp90, and FA). Kp90 showed the highest correlation with GG and the best diagnostic ability (area under the curve = 0.84) in discriminating low- from high-risk PCa.ConclusionCompared to DTI, DKI provides complementary and additional information about prostate cancer tissue, resulting more sensitive to PCa-derived modifications and more accurate in discriminating low- and high-risk PCa.
       
  • Calibrated Breast Density Measurements
    • Abstract: Publication date: Available online 10 December 2018Source: Academic RadiologyAuthor(s): Erin E. Fowler, Autumn Smallwood, Nadia Khan, Cassandra Miltich, Jennifer Drukteinis, Thomas A. Sellers, John HeineRationale and ObjectivesMammographic density is an important risk factor for breast cancer, but translation to the clinic requires assurance that prior work based on mammography is applicable to current technologies. The purpose of this work is to evaluate whether a calibration methodology developed previously produces breast density metrics predictive of breast cancer risk when applied to a case–control study.Materials and MethodsA matched case control study (n = 319 pairs) was used to evaluate two calibrated measures of breast density. Two-dimensional mammograms were acquired from six Hologic mammography units: three conventional Selenia two-dimensional full-field digital mammography systems and three Dimensions digital breast tomosynthesis systems. We evaluated the capability of two calibrated breast density measures to quantify breast cancer risk: the mean (PGm) and standard deviation (PGsd) of the calibrated pixels. Matching variables included age, hormone replacement therapy usage/duration, screening history, and mammography unit. Calibrated measures were compared to the percentage of breast density (PD) determined with the operator-assisted Cumulus method. Conditional logistic regression was used to generate odds ratios (ORs) from continuous and quartile (Q) models with 95% confidence intervals. The area under the receiver operating characteristic curve (Az) was also used as a comparison metric. Both univariate models and models adjusted for body mass index and ethnicity were evaluated.ResultsIn adjusted models, both PGsd and PD were statistically significantly associated with breast cancer with similar Az of 0.61–0.62. The corresponding ORs and confidence intervals were also similar. For PGsd, the OR was 1.34 (1.09, 1.66) for the continuous measure and 1.83 (1.11, 3.02), 2.19 (1.28, 3.73), and 2.20 (1.26, 3.85) for Q2–Q4. For PD, the OR was 1.43 (1.16, 1.76) for the continuous measure and 0.84 (0.52, 1.38), 1.96 (1.19, 3.23), and 2.27 (1.29, 4.00) for Q2–Q4. The results for PGm were slightly attenuated and not statistically significant. The OR was 1.22 (0.99, 1.51) with Az = 0.60 for the continuous measure and 1.24 (0.78, 1.97), 0.98 (0.60, 1.61), and 1.26, (0.77, 2.07) for Q2–Q4 with Az = 0.60.ConclusionThe calibrated PGsd measure provided significant associations with breast cancer comparable to those given by PD. The calibrated PGm performed slightly worse. These findings indicate that the calibration approach developed previously replicates under more general conditions.
       
  • Influence of Inspiratory/Expiratory CT Registration on Quantitative Air
           Trapping
    • Abstract: Publication date: Available online 10 December 2018Source: Academic RadiologyAuthor(s): Oliver Weinheimer, Benjamin A. Hoff, Aleksa B. Fortuna, Antonio Fernández-Baldera, Philip Konietzke, Mark O. Wielpütz, Terry E. Robinson, Craig J. GalbánRationale and ObjectivesThe aim of this study was to assess variability in quantitative air trapping (QAT) measurements derived from spatially aligned expiration CT scans.Materials and MethodsSixty-four paired CT examinations, from 16 school-age cystic fibrosis subjects examined at four separate time intervals, were used in this study. For each pair, visually inspected lobe segmentation maps were generated and expiration CT data were registered to the inspiration CT frame. Measurements of QAT, the percentage of voxels on the expiration CT scan below a set threshold were calculated for each lobe and whole-lung from the registered expiration CT and compared to the true values from the unregistered data.ResultsA mathematical model, which simulates the effect of variable regions of lung deformation on QAT values calculated from aligned to those from unaligned data, showed the potential for large bias. Assessment of experimental QAT measurements using Bland-Altman plots corroborated the model simulations, demonstrating biases greater than 5% when QAT was approximately 40% of lung volume. These biases were removed when calculating QAT from aligned expiration CT data using the determinant of the Jacobian matrix. We found, by Dice coefficient analysis, good agreement between aligned expiration and inspiration segmentation maps for the whole-lung and all but one lobe (Dice coefficient> 0.9), with only the lingula generating a value below 0.9 (mean and standard deviation of 0.85 ± 0.06).ConclusionThe subtle and predictable variability in corrected QAT observed in this study suggests that image registration is reliable in preserving the accuracy of the quantitative metrics.
       
  • Letter to the Editor: Women Representation on Radiology Journal Editorial
           Boards
    • Abstract: Publication date: January 2019Source: Academic Radiology, Volume 26, Issue 1Author(s): Prachi P. Agarwal, Sowmya Balasubramanian, Deborah Levine, Ella A Kazerooni, M Elizabeth Oates
       
  • Perception's Crucial Role in Radiology Education
    • Abstract: Publication date: January 2019Source: Academic Radiology, Volume 26, Issue 1Author(s): Richard B. Gunderman, Parth Patel
       
  • Efficacy of 3D Printed Models on Resident Learning and Understanding of
           Common Acetabular Fracturers
    • Abstract: Publication date: January 2019Source: Academic Radiology, Volume 26, Issue 1Author(s): Omer A. Awan, Maunil Sheth, Ian Sullivan, Jafar Hussain, Padmaja Jonnalagadda, Stephen Ling, Sayed AliRationale and ObjectivesThe conceptualization of acetabular fractures can present a daunting challenge to radiology residents. 3D models have been shown to aid in the spatial perception of complicated anatomy and may help residents grasp the elaborate classification systems for these anatomically complex fractures. Prior studies have explored the utility of 3D printed models for surgical planning in various settings. To our knowledge, no study has evaluated their efficacy in radiology resident training.Materials and MethodsFollowing IRB approval, 22 radiology residents were randomized and stratified by Post Graduate Year into two groups of 11 residents. Both groups received separate identical presentations on the 5 most common acetabular fractures given by a musculoskeletal trained radiologist. Residents in the experimental group received 3D printed models of the five most common fracture types with which to interact during the presentation, while the control group did not. Both groups received a pretest and a follow up posttest three weeks later.ResultsA Wilcoxon rank sum test was performed to determine if statistically significant differences between the pretest and posttest scores of the experimental and control groups existed. There was no statistically significant difference in scores on the pre-test, which confirmed successful randomization. There was a statistically significant difference (P = 0.02) on the posttest scores between the experimental and control groups.Conclusion3D printed models promise as an effective educational tool for resident learning with respect to acetabular fractures, improving short-term understanding of complex anatomy and classification systems.
       
  • A Review of Innovative Teaching Methods
    • Abstract: Publication date: January 2019Source: Academic Radiology, Volume 26, Issue 1Author(s): Rebecca T. Sivarajah, Nicole E. Curci, Elizabeth M. Johnson, Diana L. Lam, James T. Lee, Michael L. RichardsonTeaching is one of the important roles of an academic radiologist. Therefore, it is important that radiologists are taught how to effectively educate and, in turn, to act as role models of these skills to trainees. This is reinforced by the Liaison Committee on Medical Education which has the requirement that all residents who interact with and teach medical students must undergo training in effective methods of teaching. Radiologists are likely familiar with the traditional didactic lecture-type teaching format. However, there are many newer innovative teaching methods that could be added to the radiologist's teaching repertoire, which could be used to enhance the traditional lecture format. The Association of University Radiologists Radiology Research Alliance Task Force on Noninterpretive Skills therefore presents a review of several innovative teaching methods, which include the use of audience response technology, long-distance teaching, the flipped classroom, and active learning.
       
  • Practical Presentation Pearls: Evidence-based Recommendations From the
           Psychology and Physiology Literature
    • Abstract: Publication date: January 2019Source: Academic Radiology, Volume 26, Issue 1Author(s): Michael L. Richardson, Nicole E. Curci, Elizabeth M. Johnson, Diana L. Lam, James T. Lee, Rebecca T. SivarajahOral presentations remain a common teaching method in academic radiology. The goal of these presentations is to transfer knowledge from the presenter’s brain to brains in the audience in a way that sticks. A number of studies from the recent psychological and physiological literature offer some rather practical and evidence-based advice on ways to optimize our oral presentations. The purpose of this paper is to summarize this work, and to give examples of how it can be harnessed to increase the efficacy of radiology presentations, whether they are for resident education, a continuing medical education course, or for a scientific presentation at a national radiology meeting.
       
  • Breast Cyst Fluid Analysis Correlations with Speed of Sound Using
           Transmission Ultrasound
    • Abstract: Publication date: January 2019Source: Academic Radiology, Volume 26, Issue 1Author(s): Bilal H. Malik, John C. KlockRationale and ObjectivesThe purpose of this work is to determine if the speed of sound value of a breast cyst can aid in the clinical management of breast masses. Breast macrocysts are defined as fluid-filled tissue masses>1 cm in diameter and are thought to be aberrations of normal development and involution, often associated with apocrine metaplasia. The benign natural history of breast cysts is well known, and it is important to obtain high specificity in breast imaging to avoid unnecessary biopsies in women who have benign diseases, particularly those with dense breast tissue. Transmission ultrasound is a tomographic imaging modality that generates high-resolution, 3D speed of sound maps that could be used to identify breast tissue types and act as a biomarker to differentiate lesions. We performed this study to investigate the microanatomy of macrocysts observed using transmission ultrasound, as well as assess the relationship of speed of sound to the physical and biochemical parameters of cyst fluids.Materials and MethodsCyst fluid samples were obtained from 37 patients as part of a case-collection study for ultrasound imaging of the breast. The speed of sound of each sample was measured using a quantitative transmission ultrasound scanner in vivo. Electrolytes, protein, cholesterol, viscosity, and specific gravity were also measured (in the aspirated cyst fluid) to assess their relationship to the speed of sound values obtained during breast imaging.ResultsWe found positive correlations between viscosity and cholesterol (r = 0.71) and viscosity and total protein × cholesterol (r = 0.78). Additionally, we performed direct cell counts on cyst fluids and confirmed a positive correlation of number of cells with speed of sound (r = 0.74). The speed of sound of breast macrocysts, as observed using transmission ultrasound, correlated with the cytological features of intracystic cell clumps.ConclusionOn the basis of our work with speed as a classifier, we propose a spectrum of breast macrocysts from fluid-filled to highly cellular. Our results suggest high-speed cysts are mature macrocysts with high cell counts and many cellular clumps that correlate with cyst microanatomy as seen by transmission ultrasound. Further studies are needed to confirm our findings and to assess the clinical value of speed of sound measurements in breast imaging using transmission ultrasound.
       
  • Relationship between Background Parenchymal Enhancement on High-risk
           Screening MRI and Future Breast Cancer Risk
    • Abstract: Publication date: January 2019Source: Academic Radiology, Volume 26, Issue 1Author(s): Lars J. Grimm, Ashirbani Saha, Sujata V. Ghate, Connie Kim, Mary Scott Soo, Sora C. Yoon, Maciej A. MazurowskiRationale and ObjectivesTo determine if background parenchymal enhancement (BPE) on screening breast magnetic resonance imaging (MRI) in high-risk women correlates with future cancer.Materials and MethodsAll screening breast MRIs (n = 1039) in high-risk women at our institution from August 1, 2004, to July 30, 2013, were identified. Sixty-one patients who subsequently developed breast cancer were matched 1:2 by age and high-risk indication with patients who did not develop breast cancer (n = 122). Five fellowship-trained breast radiologists independently recorded the BPE. The median reader BPE for each case was calculated and compared between the cancer and control cohorts.ResultsCancer cohort patients were high-risk because of a history of radiation therapy (10%, 6 of 61), high-risk lesion (18%, 11 of 61), or breast cancer (30%, 18 of 61); BRCA mutation (18%, 11 of 61); or family history (25%, 15 of 61). Subsequent malignancies were invasive ductal carcinoma (64%, 39 of 61), ductal carcinoma in situ (30%, 18 of 61) and invasive lobular carcinoma (7%, 4of 61). BPE was significantly higher in the cancer cohort than in the control cohort (P = 0.01). Women with mild, moderate, or marked BPE were 2.5 times more likely to develop breast cancer than women with minimal BPE (odds ratio = 2.5, 95% confidence interval: 1.3–4.8, P = .005). There was fair interreader agreement (κ = 0.39).ConclusionsHigh-risk women with greater than minimal BPE at screening MRI have increased risk of future breast cancer.
       
  • Observer Variability in Breast Cancer Diagnosis between Countries with and
           without Breast Screening
    • Abstract: Publication date: January 2019Source: Academic Radiology, Volume 26, Issue 1Author(s): Delgermaa Demchig, Claudia Mello-Thoms, Warwick Lee, Khulan Khurelsukh, Asai Ramish, Patrick BrennanRational and ObjectivesImage reporting is a vital component of patient management depending on individual radiologists' performance. Our objective was to explore mammographic diagnostic efficacy in a country where breast cancer screening does not exist.Materials and MethodsTwo mammographic test sets were used: a typical screening (TS) and high-difficulty (HD) test set. Nonscreening (NS) radiologists (n = 11) read both test sets, while 52 and 49 screening radiologists read the TS and HD test sets, respectively. The screening radiologists were classified into two groups: a less experienced (LE) group with ≤5 years' experience and a more experienced (ME) group with ≥5 years' experience.A Kruskal–Wallis and Tukey–Kramer post hoc test were used to compare reading performance among reader groups, and the Wilcoxon matched pairs tests was used to compare TS and ND test sets for the NS radiologists.ResultsAcross the three reader groups, there were significant differences in case sensitivity (χ2 [2] = 9.4, P = .008), specificity (χ2 [2] = 10.3, P = .006), location sensitivity (χ2 [2] = 19.8, P 
       
  • The Use of Model-based Iterative Reconstruction to Optimize Chest CT
           Examinations for Diagnosing Lung Metastases in Patients with Sarcoma: A
           Phantom Study
    • Abstract: Publication date: January 2019Source: Academic Radiology, Volume 26, Issue 1Author(s): Touko Kaasalainen, Teemu Mäkelä, Anna Kelaranta, Mika KortesniemiRationale and ObjectivesThis phantom study aimed to evaluate low-dose (LD) chest computed tomography (CT) protocols using model-based iterative reconstruction (MBIR) for diagnosing lung metastases in patients with sarcoma.Materials and MethodsAn adult female anthropomorphic phantom was scanned with a 64-slice CT using four LD protocols and a standard-dose protocol. Absorbed organ doses were measured with 10 metal-oxide-semiconductor field-effect transistor dosimeters. Furthermore, Monte Carlo simulations were performed to estimate organ and effective doses. Image quality in terms of image noise, contrast, and resolution was measured from the CT images reconstructed with conventional filtered back projection, adaptive statistical iterative reconstruction, and MBIR algorithms. All the results were compared to the performance of the standard-dose protocol.ResultsMean absorbed organ and effective doses were reduced by approximately 95% with the LD protocol (100-kVp tube voltage and a fixed 10-mA tube current) compared to the standard-dose protocol (120-kVp tube voltage and tube current modulation) while yielding an acceptable image quality for diagnosing round-shaped lung metastases. The effective doses ranged from 0.16 to 2.83 mSv in the studied protocols. The image noise, contrast, and resolution were maintained or improved when comparing the image quality of LD protocols using MBIR to the performance of the standard-dose chest CT protocol using filtered back projection. The small round-shaped lung metastases were delineated at levels comparable to the used protocols.ConclusionsRadiation exposure in patients can be reduced significantly by using LD chest CT protocols and MBIR algorithm while maintaining image quality for detecting round-shaped lung metastases.
       
  • A Feasibility Study of Single-inhalation, Single-energy Xenon-enhanced CT
           for High-resolution Imaging of Regional Lung Ventilation in Humans
    • Abstract: Publication date: January 2019Source: Academic Radiology, Volume 26, Issue 1Author(s): Daniel W. Pinkham, Mohammadreza Negahdar, Tokihiro Yamamoto, Erik Mittra, Maximilian Diehn, Viswam S. Nair, Paul J. Keall, Peter G. Maxim, Billy W. LooRationale and ObjectivesThe objective of this study was to assess the feasibility of single-inhalation xenon-enhanced computed tomography (XeCT) to provide clinically practical, high-resolution pulmonary ventilation imaging to clinics with access to only a single-energy computed tomography scanner, and to reduce the subject's overall exposure to xenon by utilizing a higher (70%) concentration for a much shorter time than has been employed in prior studies.Materials and MethodsWe conducted an institutional review board-approved prospective feasibility study of XeCT for 15 patients undergoing thoracic radiotherapy. For XeCT, we acquired two breath-hold single-energy computed tomography images of the entire lung with a single inhalation each of 100% oxygen and a mixture of 70% xenon and 30% oxygen, respectively. A video biofeedback system for coached patient breathing was used to achieve reproducible breath holds. We assessed the technical success of XeCT acquisition and side effects. We then used deformable image registration to align the breath-hold images with each other to accurately subtract them, producing a map of lung xenon distribution. Additionally, we acquired ventilation single-photon emission computed tomography-computed tomography (V-SPECT-CT) images for 11 of the 15 patients. For a comparative analysis, we partitioned each lung into 12 sectors, calculated the xenon concentration from the Hounsfield unit enhancement in each sector, and then correlated this with the corresponding V-SPECT-CT counts.ResultsXeCT scans were tolerated well overall, with a mild (grade 1) dizziness as the only side effect in 5 of the 15 patients. Technical failures in five patients occurred because of inaccurate breathing synchronization with xenon gas delivery, leaving seven patients analyzable for XeCT and single-photon emission computed tomography correlation. Sector-wise correlations were strong (Spearman coefficient>0.75, Pearson coefficient>0.65, P value
       
  • Volumetric Textural Analysis of Colorectal Masses at CT Colonography:
           Differentiating Benign versus Malignant Pathology and Comparison with
           Human Reader Performance
    • Abstract: Publication date: January 2019Source: Academic Radiology, Volume 26, Issue 1Author(s): B. Dustin Pooler, Meghan G. Lubner, Jake R. Theis, Richard B. Halberg, Zhengrong Liang, Perry J. PickhardtRationale and ObjectivesTo (1) apply a quantitative volumetric textural analysis (VTA) to colorectal masses at CT colonography (CTC) for the differentiation of malignant and benign lesions and to (2) compare VTA with human performance.Materials and MethodsA validated, quantitative VTA method was applied to 63 pathologically proven colorectal masses (mean size, 4.2 cm; range, 3–8 cm) at noncontrast CTC in 59 adults (mean age, 66.5 years; range, 45.9–91.6 years). Fifty-one percent (32/63) of the masses were invasive adenocarcinoma, and the remaining 49% (31/63) were large benign adenomas. Three readers with CTC experience independently assessed the likelihood of malignancy using a 5-point scale (1 = definitely benign, 2 = probably benign, 3 = indeterminate, 4 = probably malignant, 5 = definitely malignant). Areas under the curve (AUCs) and accuracy levels were compared.ResultsVTA achieved optimal sensitivity of 83.6% vs 91.7% for human readers (P = .034), with specificities of 87.5% and 77.4%, respectively (P = .007). No significant difference in overall accuracy was seen between VTA and human readers (85.5% vs 84.7%, P = .753). The AUC for differentiating benign and malignant lesions was 0.936 for VTA and 0.917 for human readers. Intraclass correlation coefficient among the human readers was 0.76, indicating good to excellent agreement.ConclusionVTA demonstrates excellent performance for distinguishing benign from malignant colorectal masses (≥3 cm) at CTC, comparable yet potentially complementary to experienced human performance.
       
  • Comparison of T1 Mapping and T1rho Values with Conventional
           Diffusion-weighted Imaging to Assess Fibrosis in a Rat Model of Unilateral
           Ureteral Obstruction
    • Abstract: Publication date: January 2019Source: Academic Radiology, Volume 26, Issue 1Author(s): Genwen Hu, Wen Liang, Mingxiang Wu, Caiyong Lai, Yingjie Mei, Yufa Li, Jianmin Xu, Liangping Luo, Xianyue QuanRationale and ObjectivesThe aim of this study was to investigate the potential of magnetic resonance imaging (MRI) T1 mapping and T1 relaxation time in the rotating frame (T1rho) for assessment of renal fibrosis in a rat model of unilateral ureteral obstruction (UUO).Materials and MethodsUUO was created in 36 rats. Six rats were scanned at each of the six time points (on days 0, 1, 3, 5, 10, and 15 after UUO). The contralateral kidneys were examined as controls. Hematoxylin-eosin, Masson's trichrome, and alpha-smooth muscle actin (α-SMA) antibody staining assays were performed. MRI data obtained with a 3.0T scanner were analyzed with α-SMA expression and Masson's staining.ResultsThe T1 relaxation times and T1rho values increased, and the mean apparent diffusion coefficient (ADC) values decreased with time after UUO. Simple regression analysis indicated that the mean ADCs, T1 relaxation times, and T1rho values had strong correlations with the α-SMA expression levels (R2 = 0.34, R2 = 0.66, R2 = 0.71, respectively; P 
       
  • Performance of T2 Maps in the Detection of Prostate Cancer
    • Abstract: Publication date: January 2019Source: Academic Radiology, Volume 26, Issue 1Author(s): Aritrick Chatterjee, Ajit Devaraj, Melvy Mathew, Teodora Szasz, Tatjana Antic, Gregory S. Karczmar, Aytekin OtoRationale and ObjectivesThis study compares the performance of T2 maps in the detection of prostate cancer (PCa) in comparison to T2-weighted (T2W) magnetic resonance images.Materials and MethodsThe prospective study was institutional review board approved. Consenting patients (n = 45) with histologic confirmed PCa underwent preoperative 3-T magnetic resonance imaging with or without endorectal coil. Two radiologists, working independently, marked regions of interests (ROIs) on PCa lesions separately on T2W images and T2 maps. Each ROI was assigned a score of 1–5 based on the confidence in accurately detecting cancer, with 5 being the highest confidence. Subsequently, the histologically confirmed PCa lesions (n = 112) on whole-mount sections were matched with ROIs to calculate sensitivity, positive predictive value (PPV), and radiologist confidence score. Quantitative T2 values of PCa and benign tissue ROIs were measured.ResultsSensitivity and confidence score for PCa detection were similar for T2W images (51%, 4.5 ± 0.8) and T2 maps (52%, 4.5 ± 0.6). However, PPV was significantly higher (P = .001) for T2 maps (88%) compared to T2W (72%) images. The use of endorectal coils nominally improved sensitivity (T2W: 55 vs 47%, T2 map: 54% vs 48%) compared to the use of no endorectal coils, but not the PPV and the confidence score. Quantitative T2 values for PCa (105 ± 28 milliseconds) were significantly (P = 9.3 × 10−14) lower than benign peripheral zone tissue (211 ± 71 milliseconds), with moderate significant correlation with Gleason score (ρ = −0.284).ConclusionsOur study shows that review of T2 maps by radiologists has similar sensitivity but higher PPV compared to T2W images. Additional quantitative information obtained from T2 maps is helpful in differentiating cancer from normal prostate tissue and determining its aggressiveness.
       
  • A Multireader Exploratory Evaluation of Individual Pulse Sequence Cancer
           Detection on Prostate Multiparametric Magnetic Resonance Imaging (MRI)
    • Abstract: Publication date: January 2019Source: Academic Radiology, Volume 26, Issue 1Author(s): Sonia Gaur, Stephanie Harmon, Rajan T. Gupta, Daniel J. Margolis, Nathan Lay, Sherif Mehralivand, Maria J. Merino, Bradford J. Wood, Peter A. Pinto, Joanna H. Shih, Peter L. Choyke, Baris TurkbeyRationale and ObjectivesTo determine independent contribution of each prostate multiparametric magnetic resonance imaging (mpMRI) sequence to cancer detection when read in isolation.Materials and MethodsProstate mpMRI at 3-Tesla with endorectal coil from 45 patients (n = 30 prostatectomy cases, n = 15 controls with negative magnetic resonance imaging [MRI] or biopsy) were retrospectively interpreted. Sequences (T2-weighted [T2W] MRI, diffusion-weighted imaging [DWI], and dynamic contrast-enhanced [DCE] MRI; N = 135) were separately distributed to three radiologists at different institutions. Readers evaluated each sequence blinded to other mpMRI sequences. Findings were correlated to whole-mount pathology. Cancer detection sensitivity, positive predictive value for whole prostate (WP), transition zone, and peripheral zone were evaluated per sequence by reader, with reader concordance measured by index of specific agreement. Cancer detection rates (CDRs) were calculated for combinations of independently read sequences.Results44 patients were evaluable (cases median prostate-specific antigen 6.83 [ range 1.95–51.13] ng/mL, age 62 [45–71] years; controls prostate-specific antigen 6.85 [2.4–10.87] ng/mL, age 65.5 [47–71] years). Readers had highest sensitivity on DWI (59%) vs T2W MRI (48%) and DCE (23%) in WP. DWI-only positivity (DWI+/T2W−/DCE−) achieved highest CDR in WP (38%), compared to T2W-only (CDR 24%) and DCE-only (CDR 8%). DWI+/T2W+/DCE− achieved CDR 80%, an added benefit of 56.4% from T2W-only and of 42% from DWI-only (P 
       
  • Impact of Effective Detector Pixel and CT Voxel Size on Accurate
           Estimation of Blood Volume in Opacified Microvasculature
    • Abstract: Publication date: Available online 7 December 2018Source: Academic RadiologyAuthor(s): Mahya Sheikhzadeh, Andrew J Vercnocke, Shengzhen Tao, Kishore Rajendran, Shuai Leng, Erik L Ritman, Cynthia H. McColloughRationale and ObjectivesThe purpose of this study was to determine the impact of effective detector-pixel-size and image voxel size on the accurate estimation of microvessel density (ratio of microvascular lumen volume/tissue volume) in an excised porcine myocardium specimen using microcomputed tomography (CT), and the ability of whole-body energy-integrating-detector (EID) CT and photon-counting-detector (PCD) CT to measure microvessel density in the same ex vivo specimen.Materials and MethodsPorcine myocardial tissue in which the microvessels contained radio-opaque material was scanned using a micro-CT scanner and data were generated with a range of detector pixel sizes and image voxel sizes from 20 to 260 microns, to determine the impact of these parameters on the accuracy of microvessel density estimates. The same specimen was scanned in a whole-body EID CT and PCD CT system and images reconstructed with 600 and 250 micron slice thicknesses, respectively. Fraction of tissue volume that is filled with opacified microvessels was determined by first subtracting the mean background attenuation value from all voxels, and then by summing the remaining attenuation.ResultsMicrovessel density data were normalized to the value measured at 20 µm voxel size, which was considered reference truth for this study. For emulated micro-CT voxels up to 260 µm, the microvessel density was underestimated by at most 11%. For whole-body EID CT and PCD CT, microvessel density was underestimated by 9.5% and overestimated by 0.1%, respectively.ConclusionOur data indicate that microvessel density can be accurately calculated from the larger detector pixels used in clinical CT scanners by measuring the increase of CT attenuation caused by these opacified microvessels.
       
  • Imaging Characterization of Thyroid Nodules
    • Abstract: Publication date: Available online 6 December 2018Source: Academic RadiologyAuthor(s): Chaitanya R. Divgi
       
  • News From the Academy
    • Abstract: Publication date: Available online 6 December 2018Source: Academic RadiologyAuthor(s): Hedvig Hricak, Steven E. Seltzer
       
  • Image Quality and ADC Assessment in Turbo Spin-Echo and Echo-Planar
           Diffusion-Weighted MR Imaging of Tumors of the Head and Neck
    • Abstract: Publication date: Available online 6 December 2018Source: Academic RadiologyAuthor(s): Wannakamon Panyarak, Toru Chikui, Yasuo Yamashita, Takeshi Kamitani, Kazunori YoshiuraRationale and ObjectivesWe aimed to compare the distortion ratio (DR), signal-to-noise ratio (SNR), and contrast-to-noise ratio (CNR) between turbo spin-echo (TSE)-diffusion-weighted imaging (DWI) and echo-planar imaging (EPI)-DWI of the orofacial region and prove the usefulness of TSE-DWI for the differential diagnosis of orofacial lesions.Materials and methodsThe DR, SNR, and CNR of both sequences were compared in 42 cases. Then, the apparent diffusion coefficient (ADC) of various orofacial lesions obtained by TSE-DWI was investigated in 143 lesions.ResultsIn the first study, 38 of 42 cases were analyzed. TSE-DWI showed a significantly lower DR (p < 0.05) and higher SNR and CNR than EPI-DWI (p < 0.05), indicating the superiority of TSE-DWI. In the second study, 114 cases (79.3%) were successfully analyzed. When lesions were divided into cysts, benign tumors, squamous cell carcinoma, malignant lymphoma, and other malignant tumors (OT), significant differences were observed in all pairs of lesions (p < 0.05) except squamous cell carcinoma and OT (p = 0.877). The area under the curve for distinguishing benign from malignant tumors was 0.80 with a cutoff ADC of 1.29 × 10-3 mm²/s.ConclusionTSE-DWI produced better quality images than EPI-DWI. TSE-DWI yields the high possibility of obtaining ADC in the orofacial region, and this value was considered useful for the differential diagnosis of orofacial lesions.
       
  • Radiomics Signature: A Biomarker for the Preoperative Distant Metastatic
           Prediction of Stage I Nonsmall Cell Lung Cancer
    • Abstract: Publication date: Available online 6 December 2018Source: Academic RadiologyAuthor(s): Li Fan, MengJie Fang, WenTing Tu, Di Zhang, Yun Wang, Xiuxiu Zhou, Yi Xia, ZhaoBin Li, ShiYuan LiuObjectivesTo evaluate the predictive value of radiomics features on the distant metastasis (DM) of stage I nonsmall cell lung cancer (NSCLC) preoperatively, by comparing with clinical characteristics and CT morphological features, and to screen the important prognostic predictors.MethodsOne hundred ninety-four stage I NSCLC patients were retrospectively enrolled, DM free survival (DMFS) was evaluated. The consensus clustering analysis was used to build the radiomics signatures in the primary cohort and validated in the validation cohort. The univariate survival analysis was performed in clinical characteristics, CT morphological features and radiomics signatures, respectively. Cox model was performed and C-index was calculated.ResultsThere were 25 patients (12.9%) with DM. The median DMFS was 15 months. Three hundred thirteen radiomics features were selected, then classified into five groups, two subtypes (I and II) with each group. The RS1 showed the best prognostic ability with C-index of 0.355(95% confidence interval [CI], 0.269–0.442; p < 0.001). The histological type exhibited a good prognostic ability with C-index of 0.123 (95% CI, 0.000–0.305; p < 0.001) for DMFS. Cox model showed RS1(hazard ratio [HR] 18.025, 95% CI 2.366–137.340), pleural indentation sign (HR 2.623, 95% CI 1.070–6.426) and histological type (HR 4.461, 95% CI 1.783–11.162) were the independent prognostic factors (p < 0.05).ConclusionRadiomics provided a new modality for the distant metastatic prediction of stage I NSCLC. Patients with type II of RS1, pleural indentation sign and nonadenocarcinoma indicated the high probability of postsurgical DM.
       
  • Gadoterate Meglumine Administration in Multiple Sclerosis has no Effect on
           the Dentate Nucleus and the Globus Pallidus Signal Intensities
    • Abstract: Publication date: Available online 6 December 2018Source: Academic RadiologyAuthor(s): Salem Hannoun, Rayane Issa, Nabil K. El Ayoubi, Ribal Haddad, Marwa Baalbaki, Bassem I. Yamout, Samia J. Khoury, Roula HouraniRationale and objectivesPrevious studies on possible accumulation of gadolinium-based contrast agents (GBCA) in the brain suggest that macrocyclic GBCA are less likely to accumulate than linear GBCA. However, conflicting results have been reported, especially in MS. The aim of this study is to investigate retrospectively the correlation between gadoterate-meglumine (macrocyclic GBCA) use and T1 signal intensity changes (SI) in the dentate nucleus and the GP on unenhanced T1-weighted images in a large cohort of MS patients.Materials and methodsUnenhanced T1-weighted images of 232 MS patients who previously received multiple intravenous administrations of 0.1 mmol/kg of gadoterate-meglumine were reviewed. The change in T1 SI ratios of dentate nucleus/central pons (DN/CP) and globus pallidus/centrum semiovale (GP/CSO) was calculated between the first and last MRIs and correlated with age, number of injections, time interval between MRIs, disease duration, activity, and therapy.ResultsDN/CP ratio showed no significant changes whereas the GP/CSO ratio showed a significant decrease (p < 0.0001) between the first and last MRIs. Multivariable analyses of both ratios, controlling for age, disease duration, and time interval between MRIs, showed no significant correlation between the number of gadolinium injections and the differences in DN/CP (standardized beta = −0.018, p = 0.811) or GP/CSO SI ratios (standardized beta = −0.049, p = 0.499).ConclusionRepeated administration of gadoterate-meglumine in MS patients did not result in increased T1 SI in the DN or the GP. The significant decrease of GP/CSO ratio between the first and last MRIs is not due to gadolinium accumulation but rather to varying MR parameters.
       
  • Curating the PGY1 Year for Interventional Radiology Residency
    • Abstract: Publication date: Available online 6 December 2018Source: Academic RadiologyAuthor(s): M. Victoria Marx
       
  • Characterization of Metastatic Sternal Lesions on Dynamic
           Contrast-Enhanced Breast MRI in Women with Invasive Breast Cancer
    • Abstract: Publication date: Available online 5 December 2018Source: Academic RadiologyAuthor(s): Amie Y. Lee, Ryan Navarro, Lindsay P. Busby, Heather I. Greenwood, Matthew D. Bucknor, Kimberly M. Ray, Bonnie N. JoeRationale and ObjectivesDetecting sternal lesions is not the purpose of breast MRI, but diagnosing metastasis has major clinical implications. Our purpose was to determine the breast MRI features of sternal metastases detected on PET-CT and bone-scan.Materials and MethodsBetween 01/2010-09/2018, 379 patients with breast cancer had sternal findings on PET-CT or bone-scan, 21 of which underwent breast MRI within 100 days. Sternal lesions were considered metastatic if (1) biopsy demonstrated metastasis, (2) the lesion had similar appearance to synchronous sites of biopsy-proven osseous metastases, or (3) there were numerous suspicious lesions in which widespread osseous metastasis was presumed. Four radiologists reviewed the MR images to determine if metastases were retrospectively detectable. MRI reports were reviewed to determine if lesions were prospectively described. MRI features of metastatic sternal lesions were compared to benign controls.ResultsFourteen sternal metastases met inclusion criteria. Lesions were retrospectively detectable on breast MRI by all radiologists in 86% (12/14) of cases, but prospectively reported in 57%. Of the 12 MRI-detectable metastases, mean maximum dimension was 33 mm, 7 had>1 lesion, all were T1-hypointense, 11 were T2-hyperintense, 11 were noncircumscribed, 6 extended beyond cortex, 11 enhanced heterogeneously, and 11 demonstrated washout. Heterogeneous enhancement (p = 0.002), noncircumscribed margins (p < 0.001), multiplicity (p = 0.005), and size>1 cm (p < 0.001) were more frequent with metastatic compared to benign sternal lesions.ConclusionMost sternal metastases (86%) were retrospectively detectable on breast MRI, but only 57% were prospectively reported, emphasizing the importance evaluating the sternum on breast MRI. Certain MRI features may raise suspicion for metastasis.
       
  • Using Hyperpolarized Xenon-129 MRI to Quantify Early-Stage Lung Disease in
           Smokers
    • Abstract: Publication date: Available online 3 December 2018Source: Academic RadiologyAuthor(s): Kai Ruppert, Kun Qing, James T. Patrie, Talissa A. Altes, John P. MuglerRationale and ObjectivesHyperpolarized xenon-129 magnetic resonance (MR) provides sensitive tools that may detect early stages of lung disease in smokers before it has progressed to chronic obstructive pulmonary disease (COPD) apparent to conventional spirometric measures. We hypothesized that the functional alveolar wall thickness as assessed by hyperpolarized xenon-129 MR spectroscopy would be elevated in clinically healthy smokers before xenon MR diffusion measurements would indicate emphysematous tissue destruction.Materials and MethodsUsing hyperpolarized xenon-129 MR we measured the functional septal wall thickness and apparent diffusion coefficient of the gas phase in 16 subjects with smoking-related COPD, 9 clinically healthy current or former smokers, and 10 healthy never smokers. All subjects were age-matched and characterized by conventional pulmonary function tests. A total of 11 data sets from younger healthy never smokers were added to determine the age dependence of the septal wall thickness measurements.ResultsIn healthy never smokers the septal wall thickness increased by 0.04 μm per year of age. The healthy smoker cohort exhibited normal pulmonary function test measures that did not significantly differ from the never-smoker cohort. The age-corrected septal wall thickness correlated well with diffusion capacity for carbon monoxide (R2 = 0.56) and showed a highly significant difference between healthy subjects and COPD patients (8.8 μm vs 12.3 μm; p < 0.001), but was the only measure that actually discriminated healthy subjects from healthy smokers (8.8 μm vs 10.6 μm; p < 0.006).ConclusionFunctional alveolar wall thickness assessed by hyperpolarized xenon-129 MR allows discrimination between healthy subjects and healthy smokers and could become a powerful new measure of early-stage lung disease.
       
  • Constricting the Radiologic Lexicon: An Orwellian Errand'
    • Abstract: Publication date: Available online 3 December 2018Source: Academic RadiologyAuthor(s): Benjamin R. Gray, Richard B. Gunderman
       
  • Interview Techniques Utilized in Radiology Resident Selection—A
           Survey of the APDR
    • Abstract: Publication date: Available online 1 December 2018Source: Academic RadiologyAuthor(s): Claudia Kasales, Christine Peterson, Eric GagnonRationale and ObjectivesTo evaluate interview techniques currently used in the selection of diagnostic radiology resident candidates and to identify factors influencing the use of alternative interview techniques.Materials and MethodsAn anonymous 25 question e-mail survey was provided to 319 active members of the Association of Program Directors in Radiology. The survey included questions on residency demographics, organization of resident applicant interviews, types of interview techniques utilized, scoring and ranking of applicants, and facets of the interview/application felt most important to the selection process. Statistical analysis was performed to identify factors associated with the use of alternative interview techniques.Results93.7% of responding programs use traditional interview techniques, with 92% using unblinded, unstructured interviews, 8% blinded, unstructured interviews. Structured interview questions were incorporated in 22%. Few programs used alternative techniques like the multiple mini-interview. None of the programs used written prompts during the interview, 3% used casual visual cognitive testing, 10% used panel interview techniques, and none used formal personality testing. For ranking candidates in the match, the most important facets considered were USMLE Step scores, performance on the interview, clinical course grades, and letters of reference. Factors associated with use of alternative techniques were domains associated with program size and number of faculty.ConclusionThe majority of radiology training programs still rely upon the traditional unblinded interview technique. There is an opportunity for training programs to examine alternative techniques that reduce bias and may provide better insight into other aspects of the candidate that may not be as readily highlighted with the traditional, unblinded interview.
       
  • Quantitative Assessment of Bladder Cancer Reflects Grade and Recurrence:
           Comparing of Three Methods of Positioning Region of Interest for ADC
           Measurements at Diffusion-weighted MR Imaging
    • Abstract: Publication date: Available online 30 November 2018Source: Academic RadiologyAuthor(s): Hongyi Li, Lin Liu, Lei Ding, Zhenming Zhang, Mengchao ZhangPurposeTo determine the impact of three different regions of interests (ROIs) positioning methods for apparent diffusion coefficient (ADC) measurements on the assessment of the grade and recurrence and to examine the correlation between ADC value and histopathological grade/ Ki-67 labeling index (LI) in patients with bladder cancer.Materials and MethodsSixty-one patients with bladder cancer were retrospectively evaluated. Two observers measured mean ADC values using whole-volume-ROIs, single-section-ROI and three-ROIs methods. Interclass correlation coefficient was analyzed to assess interobserver variability. The grade and recurrence in patients with bladder cancer were assessed by calculating the areas under the receiver operating characteristic curves with Az values. Spearman's correlation was used to analyze the correlations of ADC value with grade and Ki-67 LI.ResultsFor the mean ADC value, the interclass correlation coefficient were excellent with the whole-volume and the single-section method (0.90 [95% CI: 0.84, 0.94] and 0.89 [95% CI: 0.81, 0.93]) and was good with the three-ROIs method (0.72 [95% CI: 0.53, 0.83]). The Az value for determining histological grade and recurrence of bladder cancer were not significantly different from each positioning method (all p> 0.05). There's significant correlation between histological grade and ADC measuring by whole-volume-ROIs and single-section-ROI methods (r = 0.31, p = 0.02; r = 0.37, p < 0.05). The ADC measured by whole-volume-ROIs, single-section-ROI, and three-ROIs methods were significantly and inversely correlated with the Ki-67 LI (r = −0.3; r = −0.49; r = −0.40, all p < 0.05).ConclusionThere's no significant difference among any of the ROI positioning methods in evaluation of tumor grade and recurrence. There's significant correlation between histological grade and ADC measuring by whole-volume-ROIs and single-section-ROI methods. The ADC value obtained by either of three methods was significantly and inversely correlated with the Ki-67 LI.
       
  • Radiomics for Classification of Lung Cancer Histological Subtypes Based on
           Nonenhanced Computed Tomography
    • Abstract: Publication date: Available online 28 November 2018Source: Academic RadiologyAuthor(s): Linning E, Lin Lu, Li Li, Hao Yang, Lawrence H. Schwartz, Binsheng ZhaoObjectivesTo evaluate the performance of using radiomics method to classify lung cancer histological subtypes based on nonenhanced computed tomography images.Materials and Methods278 patients with pathologically confirmed lung cancer were collected, including 181 nonsmall cell lung cancer (NSCLC) and 97 small cell lung cancers (SCLC) patients. Among the NSCLC patients, 88 patients were adenocarcinomas (AD) and 93 patients were squamous cell carcinomas (SCC). In total, 1695 quantitative radiomic features (QRF) were calculated from the primary lung cancer tumor in each patient. To build radiomic classification model based on the extracted QRFs, several machine-learning algorithms were applied sequentially. First, unsupervised hierarchical clustering was used to exclude highly correlated QRFs; second, the minimum Redundancy Maximum Relevance feature selection algorithm was employed to select informative and nonredundant QRFs; finally, the Incremental Forward Search and Support Vector Machine classification algorithms were used to combine the selected QRFs and build the model. In our work, to study the phenotypic differences among lung cancer histological subtypes, four classification models were built. They were models of SCLC vs NSCLC, SCLC vs AD, SCLC vs SCC, and AD vs SCC. The performance of the classification models was evaluated by the area under the receiver operating characteristic curve (AUC) estimated by three-fold cross-validation.ResultsThe AUC (95% confidence interval) for the model of SCLC vs NSCLC was 0.741(0.678, 0.795). For the models of SCLC vs AD and SCLC vs SCC, the AUCs were 0.822(0.755, 0.875) and 0.665(0.583, 0.738), respectively. The AUC for the model of AD vs SCC was 0.655(0.570, 0.731). Several QRFs (“Law_15,” “LoG_Uniformity,” “GLCM_Contrast,” and “Compactness Factor”) that characterize tumor heterogeneity and shape were selected as the significant features to build the models.ConclusionOur results show that phenotypic differences exist among different lung cancer histological subtypes on nonenhanced computed tomography image.
       
  • How Evolutionary Theory Illuminates Radiologic Practice: Bipedalism
    • Abstract: Publication date: December 2018Source: Academic Radiology, Volume 25, Issue 12Author(s): Richard B. Gunderman, Abdul R.S. Aasar
       
  • Enhancement of Musculoskeletal Radiology Resident Education with the Use
           of an Individual Smart Portable Ultrasound Device (iSPUD)
    • Abstract: Publication date: December 2018Source: Academic Radiology, Volume 25, Issue 12Author(s): Troy H. Maetani, Cody Schwartz, Robert J. Ward, Daniel B. NissmanRationale and ObjectivesMany medical specialties have incorporated portable ultrasound into their educational curriculum. Our objective was to determine the utility of an individual smart portable ultrasound device (iSPUD) as an educational tool in resident and fellowship Musculoskeletal Radiology training.Materials and MethodsAfter Institutional Review Board approval, volunteer radiology trainees were instructed to use the iSPUD (Philips Lumify ultrasound probe and Samsung Galaxy Tab S2 8 inch tablet), asked to identify 10 wrist structures with the iSPUD and completed a Likert scale-based, pretest survey. Trainees were then given the iSPUD for 3 days of independent scanning practice. Afterward, trainees were asked to identify the same 10 wrist structures with the iSPUD and to complete a Likert scale-based, post-test survey.ResultsTwenty trainees volunteered to participate. Trainee performance on the 10-wrist structure identification test with the iSPUD resulted in a pretest mean number correct of 2.5 ± 2.16 and a post-test mean number correct of 9.85 ± 0.37 (p < 0.001). On the pretest survey, 68.42% (13/20) had never performed and 42.11% (8/20) had never interpreted a musculoskeletal ultrasound. On the post-test survey, 18/20 (94.74%) strongly agreed that access to an iSPUD would improve their ability to perform musculoskeletal ultrasound, improve ultrasound-guided interventional skills, and help them become better Radiologists.ConclusionThe use of an iSPUD as a tool in Musculoskeletal Radiology resident and fellow education can improve clinical ultrasound skills, build trainee technical confidence during diagnostic ultrasound procedures, and help trainees achieve their goal of becoming a competent Radiologist.
       
  • Radiology Field Trips—A List of “Must Sees” in the Radiology
           Department for Medical Students: How We Do It
    • Abstract: Publication date: December 2018Source: Academic Radiology, Volume 25, Issue 12Author(s): Matthew Hartman, Sarah Thomas, Andres AyoobRationale and ObjectiveTraditionally, the radiology elective has been designed to teach medical students the fundamentals of radiologic interpretation, typically through passive means, such as didactic conferences and observational shadowing of radiologists as they interpret images. In doing so, the importance of noninterpretive skills and active learning has been minimized. Additionally, in the traditional model, students typically only gain a superficial appreciation of radiologists’ role in patient care and their interactions with clinical services, multidisciplinary teams, and patients. With the emphasis on value-focused, team-based, patient-centered care, it is important to expand the focus of radiology education beyond interpretive skills alone such that these future physicians can most effectively utilize imaging to care for patients.Materials and MethodsA list of integrated radiology field trips was created for medical students from two institutions, Allegheny Health Network and the University of Kentucky, representing a consolidation of the instructional strategies utilized at these institutions. This paradigm uses active observation to extend learning beyond the reading room.ResultsIt targets noninterpretive skills that will be of vital importance in the majority of students’ future clinical practice, such as patient safety and appropriate ordering practices.ConclusionThis article describes the integration of nine field trip experiences into a 4-week radiology clerkship and its effect on learning outcomes and student satisfaction.
       
  • Accuracy of Dual-Energy Virtual Monochromatic CT Numbers: Comparison
           between the Single-Source Projection-Based and Dual-Source Image-Based
           Methods
    • Abstract: Publication date: December 2018Source: Academic Radiology, Volume 25, Issue 12Author(s): Takashi Ueguchi, Ryota Ogihara, Sachiko YamadaRationale and ObjectivesTo investigate the accuracy of dual-energy virtual monochromatic computed tomography (CT) numbers obtained by two typical hardware and software implementations: the single-source projection-based method and the dual-source image-based method.Materials and MethodsA phantom with different tissue equivalent inserts was scanned with both single-source and dual-source scanners. A fast kVp-switching feature was used on the single-source scanner, whereas a tin filter was used on the dual-source scanner. Virtual monochromatic CT images of the phantom at energy levels of 60, 100, and 140 keV were obtained by both projection-based (on the single-source scanner) and image-based (on the dual-source scanner) methods. The accuracy of virtual monochromatic CT numbers for all inserts was assessed by comparing measured values to their corresponding true values. Linear regression analysis was performed to evaluate the dependency of measured CT numbers on tissue attenuation, method, and their interaction.ResultsRoot mean square values of systematic error over all inserts at 60, 100, and 140 keV were approximately 53, 21, and 29 Hounsfield unit (HU) with the single-source projection-based method, and 46, 7, and 6 HU with the dual-source image-based method, respectively. Linear regression analysis revealed that the interaction between the attenuation and the method had a statistically significant effect on the measured CT numbers at 100 and 140 keV.ConclusionsThere were attenuation-, method-, and energy level-dependent systematic errors in the measured virtual monochromatic CT numbers. CT number reproducibility was comparable between the two scanners, and CT numbers had better accuracy with the dual-source image-based method at 100 and 140 keV.
       
  • Comparison of Local Injection of Fresh Frozen Plasma to Traditional
           Methods of Hemostasis in Minimally Invasive Procedures
    • Abstract: Publication date: December 2018Source: Academic Radiology, Volume 25, Issue 12Author(s): John Haaga, Shiraz Rahim, Victor Kondray, Jon Davidson, Indravadan Patel, Dean NakamotoRationale and ObjectivesTo evaluate different techniques for reducing hemorrhagic complications in coagulopathic patients with elevated international normalized ratio having an image-guided percutaneous invasive procedure; techniques included systemic transfusion of fresh frozen plasma (FFP), local injection of FFP, percutaneous injection of gelatin sponge, and percutaneous placements of angiographic coils.Materials and MethodsRetrospective review of 232 consecutive patients with known coagulopathy undergoing image-guided minimally invasive procedures were selected. Ninety-one patients had local FFP injected, 40 patients underwent local synthetic gelatin injection, 16 patients had percutaneous coil embolization, and 85 patients received systemic FFP. The number of bleeds, complications related to bleeds, and systemic complications were recorded. A 30 cc threshold was used to delineate significant bleeding.ResultsNo patients experienced clinically significant or insignificant bleeding with local FFP injection (P value
       
  • Color-coded Digital Subtraction Angiography for Assessing Acute Skeletal
           Muscle Ischemia-Reperfusion Injury in a Rabbit Model
    • Abstract: Publication date: December 2018Source: Academic Radiology, Volume 25, Issue 12Author(s): Yan Zhang, Chengzhi Li, Hong Zhang, Wanghai Li, Jinwei Li, Xiaobai WangRationale and ObjectivesThis paper describes an ongoing investigation of imaging and characterization of ischemia-reperfusion (IR) and investigated the use of color-coded digital subtraction angiography (DSA) to assess reperfusion injury or potential injury.MethodsNew Zealand white rabbits were subjected to right hindlimb ischemia (IR, n = 24) or sham operation (control, n = 6). After 3 hours, the IR rabbits underwent reperfusion and were assessed at 0, 6, 12, or 24 hours (n = 6 each). DSA of the bilateral vastus lateralis muscle of each animal was performed. The maximum contrast enhancement value of a consistent region of interest in the right and left hind limbs (peak enhancement-R/L) was determined. Associations between the relative ratio of the peak right limb to the peak left limb (peak-R/L) and the following blood indicators of IR injury were analyzed: lactic dehydrogenase (LDH), creatine kinase (CK), malondialdehyde (MDA), and superoxide dismutase (SOD).ResultsSerum LDH, CK, and MDA values in each IR group were significantly higher than those of the control group and were positively associated with the IR interval, whereas SOD was significantly lower and negatively associated. The mean peak-R/L decreased linearly with the IR interval from 1.07 ± 0.01 in the control group, and 0.93 ± 0.06, 0.79 ± 0.05, 0.65 ± 0.04, and 0.47 ± 0.04 at 0, 6, 12, and 24 hours in the IR groups. The coefficients of correlation between the peak-R/L and LDH, CK, MDA, SOD serum levels were −0.885, −0.908, −0.541, and 0.832, respectively.ConclusionsColor-coded DSA may be used for monitoring the dynamics of skeletal muscle IR injury.
       
  • Predictors of Pain and Discomfort Associated with CT Arthrography of the
           Shoulder
    • Abstract: Publication date: December 2018Source: Academic Radiology, Volume 25, Issue 12Author(s): Jianhua Wang, Xiexiang Shao, Mingqian Huang, Hanlong Xin, Zhijie Zhang, Kunzheng WangRationale and ObjectivesThe objective of this study was to investigate predictors of pain associated with computed tomographic arthrography of the shoulder.Materials and MethodsBefore shoulder arthrography, all participants were assessed with the Hospital Anxiety and Depression Scale (HADS) and the World Health Organization Quality of Life Short Version Instrument (WHOQOL-BREF). The participants were nonrandomized into two groups: the anesthesia group, who underwent prior local infiltration anesthesia before shoulder arthrography, and the nonanesthesia group, who did not undergo prior local infiltration anesthesia. The pain levels at intraprocedure, at 1, 2, 6, and 12 hours, and at 1 and 2 days after injection were assessed by using a visual analog scale. Univariate and multivariate generalized linear model analyses were conducted.ResultsSixty participants in the anesthesia group and 60 participants in the nonanesthesia group were included. The pain level at intraprocedure (3.37 ± 1.94 in the anesthesia group and 3.20 ± 1.34 in the nonanesthesia group) was the highest of the whole pain course. The psychological domain (P = .0013) of WHOQOL-BREF, gender (P = .042), body mass index (P = .0001), and the total number of reinsertion and redirection of needle (P 
       
  • Determination of an Optimized Weighting Factor of Liver Parenchyma for
           Six-point Interference Dixon Fat Percentage Imaging Accuracy in
           Nonalcoholic Fatty Liver Disease Rat Model
    • Abstract: Publication date: December 2018Source: Academic Radiology, Volume 25, Issue 12Author(s): Onseok Lee, Suk-Jun Lee, Seung-Man YuRationale and ObjectivesThe aim of this study was to determine the optimal weighting factor (WF) for precise quantification using six-point interference Dixon fat percentage imaging by analyzing changes in WFs of fatty acid metabolites (FMs) in high-fat-induced fatty liver disease rat model.Materials and MethodsIndividual FM-related WFs were calculated based on concentration ratios of integrated areas of seven peak FMs with four phantom series. Ten 8-week-old male Sprague-Dawley rats were used for baseline quantification of fat in liver magnetic resonance imaging or magnetic resonance spectroscopy data. These seven lipid metabolites were then quantitatively analyzed. Spearman test was used for correlation analysis of different lipid proton concentrations. The most accurate WF for six-point interference Dixon fat percentage imaging was then determined.ResultsThe seven lipid resonance WF values obtained from magnetic resonance spectroscopy data for three different oils (oleic, linoleic, and soybean) were different from each other. In lipid phantoms, except for the phantom containing oleic acid, changes in FP values were significantly different when WFs were changed in six-point interference Dixon fat percentage image. The seven lipid resonance WF values for the nonalcoholic fatty liver animal model were different from human subcutaneous adipose tissue lipid WF values.ConclusionsWF affected the calculation of six-point interference Dixon-based fat percentage imaging value in phantom experiment. If WF of liver parenchyma FM which is specific to each liver disease is applied, the accuracy of six-point interference Dixon fat percentage imaging can be further increased.
       
  • Breast Lesions Detected via Molecular Breast Imaging: Physiological
           Parameters Affecting Interpretation
    • Abstract: Publication date: December 2018Source: Academic Radiology, Volume 25, Issue 12Author(s): Jason G. Ching, Rachel F. BremRationale and ObjectivesTo evaluate correlations between molecular breast imaging (MBI) descriptor characteristics and positive predictive value (PPV) in detecting breast cancer.Materials and MethodsA retrospective review was performed on 193 suspicious findings from 153 women (31–81 years) with positive MBI examinations. We assessed associations between (i) lesion pattern (mass vs. nonmass) and PPV; (ii) lesion pattern and suspected likelihood of cancer (low vs. moderate vs. high); (iii) background parenchymal uptake (BPU) (homogeneous vs. heterogeneous) and PPV; (iv) breast density (dense vs. non-dense) and PPV; and (v) BPU and density.ResultsOne hundred ten of 153 patients were diagnosed with malignancy or high-risk pathology (PPV1 = 71.9%), and 130/193 biopsies resulted in malignant or high-risk lesions (PPV3 = 67.4%). Biopsies of mass vs. nonmass findings had comparable PPV3 (71.7% vs. 61.3%; P = .0717). Mass findings were correlated with higher suspicion for cancer than nonmass findings (P 
       
  • Posterior Inferior Cerebellar Artery Aneurysm: Have You Ever Been
           Misdiagnosed'
    • Abstract: Publication date: December 2018Source: Academic Radiology, Volume 25, Issue 12Author(s): Yuan Zhang, Shiqing Sun, Qi Xu, Weihua Feng, Haisong ChenRationale and ObjectivesThe posterior inferior cerebellar artery aneurysm (PICAA), especially distal PICAA, is easily missed by a doctor, leading to misdiagnosis and treatment delays. The objective of this article is to report the computed tomography angiography (CTA) presentations of 30 cases of PICAA proved by digital subtraction angiography (DSA) or surgical operation, and analyze the causes of misdiagnosis of PICAA by CTA.Materials and MethodsThirty cases of patients with PICAA that were proved by DSA or surgical operation were included in this study, all of whom underwent CTA before surgical procedure. The relationship between the locations of PICAA and the rates of missed diagnosis by CTA was analyzed. The detection rates of the PICAA by volume rendering (VR) images and original thin axial images of CTA were compared.ResultsTwelve cases (12 of 30, 40%) of aneurysm lied on the proximal end of posterior inferior cerebellar artery (PICA) (border with vertebral artery) and all of them (12 of 12,100%) were clearly displayed on the VR images of CTA and correctly diagnosed by doctors. Eighteen cases (18 of 30, 60%) of aneurysm lied on the distal part of the PICA, whereas only 2 of them (2/18, 11.1%) were displayed on the VR images and correctly diagnosed before surgical procedure. After surgical operation, the respective review of the CTA images demonstrated that all aneurysms (30 of 30, 100%) can be found on the thin axial images after careful observation and are shown on VR images after adjusting the display threshold when the locations of the PICAA through thin axial images were known, including the distal PICAA.ConclusionsThin axial CT images are most important and reliable for the detection of distal PICAA. Overdependence on three-dimensional VR images of CTA is the main cause of misdiagnosis.
       
  • Chest X-ray Interpretation by Radiographers Is Not Inferior to
           Radiologists: A Multireader, Multicase Comparison Using JAFROC (Jack-knife
           Alternative Free-response Receiver Operating Characteristics) Analysis
    • Abstract: Publication date: December 2018Source: Academic Radiology, Volume 25, Issue 12Author(s): Nick Woznitza, Keith Piper, Stephen Burke, Graham BothamleyRationale and ObjectivesChest X-rays (CXR) are one of the most frequently requested imaging examinations and are fundamental to many patient pathways. The aim of this study was to investigate the diagnostic accuracy of CXR interpretation by reporting radiographers (technologists).MethodsA cohort of consultant radiologists (n = 10) and reporting radiographers (technologists; n = 11) interpreted a bank (n = 106) of adult CXRs that contained a range of pathologies. Jack-knife alternate free-response receiver operating characteristic (JAFROC) methodology was used to determine the performance of the observers (JAFROC v4.2). A noninferiority approach was used, with a predefined margin of clinical insignificance of 10% of average consultant radiologist diagnostic accuracy.ResultsThe diagnostic accuracy of the reporting radiographers (figure of merit = 0.828, 95% confidence interval 0.808–0.847) was noninferior to the consultant radiologists (figure of merit = 0.788, 95% confidence interval 0.766–0.811), P 
       
  • A Radiomics Signature in Preoperative Predicting Degree of Tumor
           Differentiation in Patients with Non–small Cell Lung Cancer
    • Abstract: Publication date: December 2018Source: Academic Radiology, Volume 25, Issue 12Author(s): Xin Chen, Mengjie Fang, Di Dong, Xinhua Wei, Lingling Liu, Xiangdong Xu, Xinqing Jiang, Jie Tian, Zaiyi LiuRationale and ObjectivesPoorly differentiated non–small cell lung cancer (NSCLC) indicated a poor prognosis and well-differentiated NSCLC indicates a noninvasive nature and good prognosis. The purpose of this study was to build and validate a radiomics signature to predict the degree of tumor differentiation (DTD) for patients with NSCLC.Materials and MethodsA total of 487 patients with pathologically diagnosed NSCLC were retrospectively included in our study. Five hundred ninety-one radiomics features were extracted from each tumor from the contrast-enhanced computed tomography images. A minimum redundancy maximum relevance algorithm and a logistic regression model were used for dimension reduction, feature selection, and radiomics signature building. The performance of the radiomics signature was assessed using receiver operating characteristic analysis, and the area under the receiver operating characteristic curve (AUC), sensitivity, specificity, and accuracy were calculated to quantify the association between a signature and DTD. An independent validation set contained 184 consecutive patients with NSCLC.ResultsA nine-radiomics-feature-based signature was built and it could differentiate low and high DTDs in the training set (AUC = 0.763, sensitivity = 0.750, specificity = 0.665, and accuracy = 0.687), and the radiomics signature had good discrimination performance in the validation set (AUC = 0.782, sensitivity = 0.608, specificity = 0.752, and accuracy = 0.712).ConclusionsA radiomics signature based on contrast-enhanced computed tomography imaging is a potentially useful imaging biomarker for differentiating low from high DTD in patients with NSCLC.
       
  • MRI-derived Regional Biventricular Function in Patients with Chronic
           Thromboembolic Pulmonary Hypertension Before and After Pulmonary
           Endarterectomy
    • Abstract: Publication date: December 2018Source: Academic Radiology, Volume 25, Issue 12Author(s): Sabine K. Maschke, Christian O. Schoenfeld, Till F. Kaireit, Serghei Cebotari, Karen Olsson, Marius Hoeper, Frank Wacker, Jens Vogel-ClaussenRationale and ObjectivesThe aim of this study was to assess regional myocardial function in patients with chronic thromboembolic hypertension (CTEPH) before and after successful pulmonary endarterectomy (PEA) using magnetic resonance imaging.MethodsTwenty-two patients with CTEPH underwent cardiac magnetic resonance imaging before and 12 (11, 17) days after PEA. Mean pulmonary artery pressure was evaluated preoperatively by right heart catheterization and during post-PEA intensive care unit-stay using a Swan-Ganz catheter. Biventricular peak systolic longitudinal, radial, circumferential strain and time-to-peak strain were obtained by tissue-tracking analysis.ResultsMean pulmonary artery pressure decreased (46 mm Hg (34.5, 55) to 24 mm Hg (16, 27); P 
       
  • Variability of CT Airways Measurements in COPD Patients Between Morning
           and Afternoon: Comparisons to Variability of Spirometric Measurements
    • Abstract: Publication date: December 2018Source: Academic Radiology, Volume 25, Issue 12Author(s): Maxime Hackx, Elodie Gyssels, Tiago Severo Garcia, Isabelle De Meulder, Marie Bruyneel, Alain Van Muylem, Vincent Ninane, Pierre Alain GevenoisRationale and ObjectivesComputed tomography (CT) airways measurements can be used as surrogates to spirometric measurements for assessing bronchodilation in a particular patient with chronic obstructive pulmonary disease. Although spirometric measurements show variations within the opening hours of a hospital department, we aimed to compare the variability of CT airways measurements between morning and afternoon in patients with chronic obstructive pulmonary disease to that of spirometric measurements.Materials and MethodsTwenty patients had pulmonary function tests and CT around 8 am and 4 pm. Luminal area (LA) and wall thickness (WT) of third and fourth generation airways were measured twice by three readers. The percentage of airway area occupied by the wall (WA%) and the square root of wall area at an internal perimeter of 10 mm (√WAPi10) were calculated. The effects of examination time, reader, and measurement session on CT airways measurements were assessed, and the variability of these measurements was compared to that of spirometric measurements.ResultsVariability of LA3rd and LA4th was greater than that of spirometric measurements (P values ranging from .999).ConclusionAs the variability of LA3rd and LA4th is greater than that of spirometric measurements, clinical studies should include cohorts with larger numbers of patients when considering LA than when considering spirometric measurements as end points.
       
  • Quantitative Analysis of Airway Tree in Low-dose Chest CT with a New
           Model-based Iterative Reconstruction Algorithm: Comparison to Adaptive
           Statistical Iterative Reconstruction in Routine-dose CT
    • Abstract: Publication date: December 2018Source: Academic Radiology, Volume 25, Issue 12Author(s): Yongjun Jia, Xing Ji, Taiping He, Yong Yu, Nan Yu, Haifeng Duan, Youmin GuoObjectiveWe aimed to evaluate a new model-based iterative reconstruction (MBIRn) algorithm either with spatial resolution and noise reduction balance (MBIRSTND) or spatial resolution preference (MBIRRP20) for quantitative analysis of airway in low-dose chest computed tomography (CT) with a computer-aided detection (CAD) software, in comparison to adaptive statistical iterative reconstruction (ASIR) in routine-dose CT.MethodsThirty patients who underwent both the routine-dose (noise index [NI] = 14 HU) and low-dose (at 30% level with NI = 28 HU) CT examination for pulmonary disease were included. Image acquisition was performed with 120 kVp tube voltage and automatic tube current modulation. Routine-dose scans were reconstructed with ASIR, whereas low-dose scans were reconstructed with ASIR, MBIRSTND, and MBIRRP20. Airway dimensions of the right middle lobe bronchus from the four reconstructions were measured using CAD software. Two radiologists used a semiquantitative 5 scoring criteria (−2, inferior to; +2, superior to; −1 slightly inferior to; +1, slightly superior to; and 0, equal to ASIR in routine-dose CT) to rate the subjective image quality of MBIRSTND and MBIRRP20 of airway trees. The paired t test and Wilcoxon signed-rank test were used for statistical comparison.ResultsThe low-dose CT provided 70.76% dose reduction compared to the routine-dose CT (0.88 ± 0.83 mSv vs 3.01 ± 1.89 mSv). MBIRSTND and MBIRRP20 with low-dose CT provided longer bronchial length measurements and were better in measurement variability and continuity and completeness of bronchial walls than ASIR in routine-dose CT (P 
       
  • It is About "Time": Academic Neuroradiologist Time Distribution for
           Interpreting Brain MRIs
    • Abstract: Publication date: December 2018Source: Academic Radiology, Volume 25, Issue 12Author(s): Altaib Al Yassin, Mohammad Salehi Sadaghiani, Suyash Mohan, R. Nick Bryan, Ilya NasrallahRationale and ObjectivesEfficiency is central to current radiology practice. Knowledge of report generation timing is essential for workload optimization and departmental staffing decisions. Yet little research evaluates the distribution of activities performed by neuroradiologists in daily work.Materials and MethodsThis observational study tracked radiologists interpreting 358 brain magnetic resonance imaging (MRI) in an academic practice over 9 months. We measured the total duration from study opening to report signing and times for five activities performed during this period: image viewing, report transcription, obtaining clinical data, education, and other. Attendings, fellows, and residents reading studies independently and attendings over-reading trainee-previewed studies were observed.ResultsTen attendings, 12 fellows, and 13 residents spent a mean of 11, 18, and 16 minutes reading brain MRIs independently. Mean duration was significantly different comparing attendings in all assignments to fellows (18.36 ± 1.05 minutes, p = 0.0001) or residents (16.31 ± 1.11 minutes, p = 0.001) but not between fellows/residents. Mean duration among attendings reading independently versus over-reading trainees was not statistically different. Attendings spent the same time on image viewing (4.07–5.33 minutes) with or without trainees. Attending transcription time was shortest when over-reading trainees (2.24 minutes) and longest when reading independently (4.20 minutes), demonstrating benefit of the draft report. Fellows and Residents spent longer on image viewing (7.14 minutes and 8.06 minutes, respectively) and transcription (7.02 minutes and 5.40 minutes, respectively) than attendings reading independently.ConclusionNeuroradiologist time/activity distributions for reading brain MRI studies were measured, setting the stage to establish a benchmark for future reference and suggesting opportunities for greater efficiency. Furthermore, report production time can be decreased when a draft report is available.
       
  • Implementation of an Innovative Tablet-based Curriculum for Radiology
           Resident Education
    • Abstract: Publication date: December 2018Source: Academic Radiology, Volume 25, Issue 12Author(s): Mina S. Makary, Summit H. Shah, Rose J. Miller, Steven P. Doukides, Mark A. KingRationale and ObjectivesThe aim of this study was to prospectively examine the impact of a tablet-based curriculum on the radiology resident educational experience.Materials and MethodsA comprehensive tablet-based curriculum was developed by creating subspecialty modules with appropriate content level for each required rotation at our diagnostic radiology residency program. Daily assignments included key learning points, readings, and reference presentation slides, covering all objectives published by the ABR Core Exam Study Guide. Residents were provided with iPad devices preconfigured with the curriculum and online access to most major radiology textbooks available in our institutional digital library. Assessment surveys were administered at baseline and 12 months following curriculum implementation.ResultsTwenty-two residents completed both surveys. In comparing the pre versus postsurvey results, 32% versus 73% residents agreed or strongly agreed that study resources were well-organized, 41% versus 91% agreed or strongly agreed that study resources were easily accessible, 27% versus 77% agreed or strongly agreed that the modules encouraged active learning, 18% versus 82% agreed or strongly agreed that resources motivate them to study daily, 36% versus 82% agreed or strongly agreed that the resources adequately prepared the resident for the radiology board exam, and 36% versus 82% agreed or strongly agreed that they were satisfied with the resources provided by the residency program (p < 0.05).ConclusionOur study demonstrated the positive impact of implementing a complete tablet-based curriculum on radiology resident motivation, satisfaction, and engagement. Use of mobile tablet devices has the potential to dramatically transform content delivery in residency education.
       
  • When Residents Hear the Bell Toll
    • Abstract: Publication date: Available online 23 November 2018Source: Academic RadiologyAuthor(s): Jared R Shields, Richard B Gunderman
       
  • Machine Learning Algorithms Utilizing Functional Respiratory Imaging May
           Predict COPD Exacerbations
    • Abstract: Publication date: Available online 23 November 2018Source: Academic RadiologyAuthor(s): Maarten Lanclus, Johan Clukers, Cedric Van Holsbeke, Wim Vos, Glenn Leemans, Birgit Holbrechts, Katherine Barboza, Wilfried De Backer, Jan De BackerRationale and ObjectivesAcute chronic obstructive pulmonary disease exacerbations (AECOPD) have a significant negative impact on the quality of life and accelerate progression of the disease. Functional respiratory imaging (FRI) has the potential to better characterize this disease. The purpose of this study was to identify FRI parameters specific to AECOPD and assess their ability to predict future AECOPD, by use of machine learning algorithms, enabling a better understanding and quantification of disease manifestation and progression.Materials and MethodsA multicenter cohort of 62 patients with COPD was analyzed. FRI obtained from baseline high resolution CT data (unenhanced and volume gated), clinical, and pulmonary function test were analyzed and incorporated into machine learning algorithms.ResultsA total of 11 baseline FRI parameters could significantly distinguish ( p < 0.05) the development of AECOPD from a stable period. In contrast, no baseline clinical or pulmonary function test parameters allowed significant classification. Furthermore, using Support Vector Machines, an accuracy of 80.65% and positive predictive value of 82.35% could be obtained by combining baseline FRI features such as total specific image-based airway volume and total specific image-based airway resistance, measured at functional residual capacity. Patients who developed an AECOPD, showed significantly smaller airway volumes and (hence) significantly higher airway resistances at baseline.ConclusionThis study indicates that FRI is a sensitive tool (PPV 82.35%) for predicting future AECOPD on a patient specific level in contrast to classical clinical parameters.
       
  • Repeatability of Regional Lung Ventilation Quantification Using
           Fluorinated (19F) Gas Magnetic Resonance Imaging
    • Abstract: Publication date: Available online 22 November 2018Source: Academic RadiologyAuthor(s): Marcel Gutberlet, Till F. Kaireit, Andreas Voskrebenzev, Agilo L. Kern, Arnd Obert, Frank Wacker, Jens M. Hohlfeld, Jens Vogel-ClaussenRationale and ObjectivesTo assess the repeatability of global and regional lung ventilation quantification in both healthy subjects and patients with chronic obstructive pulmonary disease (COPD) using fluorinated (19F) gas washout magnetic resonance (MR) imaging in free breathing.Material and MethodsIn this prospective institutional review board-approved study, 12 healthy nonsmokers and eight COPD patients were examined with 19F dynamic gas washout MR imaging in free breathing and with lung function testing. Measurements were repeated within 2 weeks. Lung ventilation was quantified using 19F gas washout time. Repeatability was analyzed for the total lung and on a regional basis using the coefficient of variation (COV) and Bland–Altman plots.ResultsIn healthy subjects and COPD patients, a good repeatability was found for lung ventilation quantification using dynamic 19F gas washout MR imaging on a global (COV < 8%) and regional (COV < 15%) level. Gas washout time was significantly increased in the COPD group compared to the healthy subjects.Conclusion19F gas washout MR imaging provides a good repeatability of lung ventilation quantification and appears to be sensitive to early changes of regional lung function alterations such as normal aging.
       
  • Selection of Fitting Model and Arterial Input Function for Repeatability
           in Dynamic Contrast-Enhanced Prostate MRI
    • Abstract: Publication date: Available online 20 November 2018Source: Academic RadiologyAuthor(s): Sharon Peled, Mark Vangel, Ron Kikinis, Clare M. Tempany, Fiona M. Fennessy, Andrey FedorovRationale and ObjectivesAnalysis of dynamic contrast-enhanced (DCE) magnetic resonance imaging is notable for the variability of calculated parameters. The purpose of this study was to evaluate the level of measurement variability and error/variability due to modeling in DCE magnetic resonance imaging parameters.Materials and MethodsTwo prostate DCE scans were performed on 11 treatment-naïve patients with suspected or confirmed prostate peripheral zone cancer within an interval of less than two weeks. Tumor-suspicious and normal-appearing regions of interest (ROI) in the prostate peripheral zone were segmented. Different Tofts-Kety based models and different arterial input functions, with and without bolus arrival time (BAT) correction, were used to extract pharmacokinetic parameters. The percent repeatability coefficient (%RC) of fitted model parameters Ktrans, ve, and kep was calculated. Paired t-tests comparing parameters in tumor-suspicious ROIs and in normal-appearing tissue evaluated each parameter's sensitivity to pathology.ResultsAlthough goodness-of-fit criteria favored the four-parameter extended Tofts-Kety model with the BAT correction included, the simplest two-parameter Tofts-Kety model overall yielded the best repeatability scores. The best %RC in the tumor-suspicious ROI was 63% for kep, 28% for ve, and 83% for Ktrans . The best p values for discrimination between tissues were p
       
  • A Note of Thanks
    • Abstract: Publication date: Available online 16 November 2018Source: Academic RadiologyAuthor(s): N. Reed Dunnick
       
  • Role of Iterative Reconstruction Algorithm for the Assessment of
           Myocardial Infarction with Dual Energy Computed Tomography
    • Abstract: Publication date: Available online 12 November 2018Source: Academic RadiologyAuthor(s): Gaston A. Rodriguez-Granillo, Alejandro Deviggiano, Carlos Capunay, Macarena De Zan, Carlos Fernandez-Pereira, Patricia CarrascosaRationale and ObjectivesLow monochromatic energy levels (40 keV) derived from delayed enhancement dual energy cardiac computed tomography (DE-DECT) allow the evaluation of myocardial infarcts (MI) among stable patients, although at the expense of high image noise. We explored whether the application of adaptive statistical iterative reconstruction (ASIR) to 40-keV DE-DECT (unavailable with previous software versions) might improve image quality and detection of MI in stable patients.Materials and MethodsWe prospectively enrolled patients with a history of previous MI, and performed delayed-enhancement cardiac magnetic resonance (DE-CMR) and DE-DECT within the same week. DE-DECT images were reconstructed with 0% and 60% ASIR.ResultsMI was identified in 18 (80%) patients with both DE-CMR and DE-DECT. On a per segment basis, we did not identify significant differences regarding the diagnostic performance of DE-DECT with and without ASIR [area under receiver operating characteristic curve 0.86 vs. 0.83, p = 0.10]. The application of ASIR improved the signal-to-noise ratio of DE-DECT with 0% ASIR compared to DE-DECT with 60% ASIR (6.07 ± 2.1 vs. 11.1 ± 4.5, p < 0.0001). However, qualitative assessment of MI image quality (3.35 ± 1.2, vs. 3.55 ± 1.1, p = 0.10) and diagnostic confidence (4.40 ± 0.9 vs. 4.60 ± 0.8, p = 0.10) were not significantly improved. Using DE-DECT with 60% ASIR, a threshold over 199 HU showed a sensitivity of 67% and a specificity of 92% for the detection of segments with MI.ConclusionIn this study, DE-DECT allowed accurate detection of MI among stable patients compared with DE-CMR, and the application of ASIR improved signal-to-noise ratio of DE-DECT, although the diagnostic performance showed only non-significant improvements.
       
  • Influence of Artificial Intelligence on Canadian Medical Students'
           Preference for Radiology Specialty: A National Survey Study
    • Abstract: Publication date: Available online 11 November 2018Source: Academic RadiologyAuthor(s): Bo Gong, James P. Nugent, William Guest, William Parker, Paul J. Chang, Faisal Khosa, Savvas NicolaouRationale and ObjectivesArtificial intelligence (AI) has the potential to transform the clinical practice of radiology. This study investigated Canadian medical students’ perceptions of the impact of AI on radiology, and their influence on the students’ preference for radiology specialty.Materials and MethodsIn March 2018, an anonymous online survey was distributed to students at all 17 Canadian medical schools.ResultsAmong 322 respondents, 70 students considered radiology as the top specialty choice, and 133 as among the top three choices. Only a minority (29.3%) of respondents agreed AI would replace radiologists in foreseeable future, but a majority (67.7%) agreed AI would reduce the demand for radiologists. Even among first-choice respondents, 48.6% agreed AI caused anxiety when considering the radiology specialty. Furthermore, one-sixth of respondents who would otherwise rank radiology as the first choice would not consider radiology because of the anxiety about AI. Prior significant exposure to radiology and high confidence in understanding of AI were shown to decrease the anxiety level. Interested students valued the opinions of local radiologists, radiology conferences, and journals. Students were most interested in “expert opinions on AI” and “discussing AI in preclinical radiology lectures” to understand the impact of AI.ConclusionAnxiety related to “displacement” (not “replacement”) of radiologists by AI discouraged many medical students from considering the radiology specialty. The radiology community should educate medical students about the potential impact of AI, to ensure radiology is perceived as a viable long-term career choice.
       
  • Texture Analysis Based on Preoperative Magnetic Resonance Imaging (MRI)
           and Conventional MRI Features for Predicting the Early Recurrence of
           Single Hepatocellular Carcinoma after Hepatectomy
    • Abstract: Publication date: Available online 10 November 2018Source: Academic RadiologyAuthor(s): Jing Zhang, Xinjie Liu, Haiping Zhang, Xiaojing He, Yangyang Liu, Jun Zhou, Dajing GuoRationale and ObjectivesTo investigate the value of texture analysis and conventional magnetic resonance imaging (MRI) features for predicting the early recurrence (ER) of single hepatocellular carcinoma (HCC) after hepatectomy.Materials and MethodsA total of 100 HCC patients were first divided into group A (tumor diameter ≤3 cm) and group B (tumor diameter>3 cm) and then classified into two subgroups with ER or nonearly recurrence. Textural parameters (skewness, kurtosis, uniformity, energy, entropy, and correlation) based on MR images and conventional MRI features were compared between the ER and nonearly recurrence subgroups. Predictive factors for ER were further assessed with multivariate logistic regression analysis. Receiver operating characteristic curve was performed to assess the predictive power.ResultsThere were 53 patients in group A and 47 patients in group B. On arterial phase analysis, tumors with ER displayed significantly lower uniformity and higher entropy in group A, and higher skewness and entropy in group B. On portal venous phase analysis, tumors with ER had significantly lower kurtosis and energy in group A, and higher entropy in group B. Irregular margin in groups A and B, and arterial peritumoral enhancement and capsule presence in group B were associated with ER. In multivariate logistic regression analysis, uniformity and entropy based on arterial phase images and irregular margin in group A, and skewness and entropy based on arterial phase images and arterial peritumoral enhancement in group B were independent predictors for ER. Entropy displayed higher predictive power for ER.ConclusionTexture analysis based on preoperative MRI are potential quantitative predictors of ER in HCC patients after hepatectomy, and may provide more information for preoperative treatment decision-making and follow up.
       
  • Diagnostic Accuracy of CT for Prediction of Bladder Cancer Treatment
           Response with and without Computerized Decision Support
    • Abstract: Publication date: Available online 10 November 2018Source: Academic RadiologyAuthor(s): Kenny H. Cha, Lubomir M. Hadjiiski, PhD, Richard H. Cohan, MD, Heang-Ping Chan, PhD, Elaine M. Caoili, MD, Matthew Davenport, MD, Ravi K. Samala, PhD, Alon Z. Weizer, MD, Ajjai Alva, MD, Galina Kirova-Nedyalkova, MD, PhD, Kimberly Shampain, MD, Nathaniel Meyer, MD, Daniel Barkmeier, MD, PhD, Sean Woolen, MD, Prasad R. Shankar, MD, Isaac R. Francis, MD, Phillip Palmbos, MDRationale and ObjectivesTo evaluate whether a computed tomography (CT)-based computerized decision-support system for muscle-invasive bladder cancer treatment response assessment (CDSS-T) can improve identification of patients who have responded completely to neoadjuvant chemotherapy.Materials and MethodsFollowing Institutional Review Board approval, pre-chemotherapy and post-chemotherapy CT scans of 123 subjects with 157 muscle-invasive bladder cancer foci were collected retrospectively. CT data were analyzed with a CDSS-T that uses a combination of deep-learning convolutional neural network and radiomic features to distinguish muscle-invasive bladder cancers that have fully responded to neoadjuvant treatment from those that have not. Leave-one-case-out cross-validation was used to minimize overfitting. Five attending abdominal radiologists, four diagnostic radiology residents, two attending oncologists, and one attending urologist estimated the likelihood of pathologic T0 disease (complete response) by viewing paired pre/post-treatment CT scans placed side-by-side on an internally-developed graphical user interface. The observers provided an estimate without use of CDSS-T and then were permitted to revise their estimate after a CDSS-T-derived likelihood score was displayed. Observer estimates were analyzed with multi-reader, multi-case receiver operating characteristic methodology. The area under the curve (AUC) and the statistical significance of the difference were estimated.ResultsThe mean AUCs for assessment of pathologic T0 disease were 0.80 for CDSS-T alone, 0.74 for physicians not using CDSS-T, and 0.77 for physicians using CDSS-T. The increase in the physicians' performance was statistically significant (P < .05).ConclusionCDSS-T improves physician performance for identifying complete response of muscle-invasive bladder cancer to neoadjuvant chemotherapy.
       
  • Quantitative Assessment of Tumor Cell Proliferation in Brain Gliomas with
           Dynamic Contrast-Enhanced MRI
    • Abstract: Publication date: Available online 8 November 2018Source: Academic RadiologyAuthor(s): Jia Shen Jiang, Ye Hua, Xue Jun Zhou, Dan Dan Shen, Jin Long Shi, Min Ge, Qi Nan Geng, Zhong Zheng JiaRationale and ObjectivesThis study aimed to investigate whether volume transfer constant (Ktrans) and volume of extravascular extracellular space per unit volume of tissue (Ve) derived from dynamic contrast-enhanced magnetic resonance imaging (DCE MRI) could quantitatively assess the tumor proliferation index (Ki-67) of gliomas noninvasively.Materials and MethodsThe preoperative DCE MRI data of 69 patients with pathologically confirmed glioma (28, 8, and 33 cases in grades Ⅱ, Ⅲ, and Ⅳ) were retrospectively reviewed. The maximal Ktrans and Ve were measured in the tumor body. The immunohistochemistry was used to detect the expression of Ki-67 proteins in glioma specimens. The Mann–Whitney U test was applied to analyze the differences in Ktrans, Ve, and Ki-67 index across histologically defined glioma grades. Spearman correlation was performed between Ktrans, Ve, and Ki-67 index. The receiver operating characteristic curve analysis was used to determine the cutoff values of Ktrans and Ve in distinguishing different Ki-67 index expression levels.ResultsKtrans, Ve, and Ki-67 index of grade Ⅱ (0.027 min−1, 0.065, 4.04%) were significantly lower than those of grade Ⅲ (0.093 min−1, 0.297, 25.13%) and Ⅳ (0.100 min−1, 0.299, 25.37%). Both Ktrans and Ve significantly correlated with the Ki-67 index in all tumors and high-grade gliomas (HGGs, grade Ⅲ and Ⅳ). The receiver operating characteristic curve analysis revealed that the cutoff values for Ktrans (0.079 min−1) and Ve (0.249) provided the best combination of sensitivity and specificity to distinguish the gliomas with high Ki-67 index from those with low Ki-67 index.ConclusionThe DCE MRI-derived parameters were valuable in assessing the tumor cell proliferation in HGG noninvasively.
       
  • Cost-Effectiveness Analysis: An Overview of Key Concepts, Recommendations,
           Controversies, and Pitfalls
    • Abstract: Publication date: Available online 8 November 2018Source: Academic RadiologyAuthor(s): Nadja Kadom, Jason N. Itri, Anna Trofimova, Hansel J. Otero, Michal HornýThe field of radiology has witnessed a burst of technological advances that improve diagnostic quality, reduce harm to patients, support clinical needs, and better serve larger more diverse patient populations. One of the critical challenges with these advances is proving that value outweighs the cost. The use of cutting-edge technology is often expensive, and the reality is that our society cannot afford all the screening and diagnostic tests that are being developed. At the societal level, we need tools to help us decide which health programs should be funded. Therefore, decision makers are increasingly looking toward scientific methods to compare health technologies in order to improve allocation of resources. One of such methods is cost-effectiveness analysis. In this article, we review key features of cost-effectiveness analysis and its specific issues as they relate to radiology.
       
  • Leadless Cardiac Pacemaker (LCP) without Diagnostic Relevant Artifacts in
           DualSource and DualEnergy-CT Examinations in First- to Third-Generation
           DSCT Scanner
    • Abstract: Publication date: Available online 7 November 2018Source: Academic RadiologyAuthor(s): Sebastian D. Reinartz, Robin F. Gohmann, Felix Hardt, Jonas Schmoee, Timm Dirrichs, Eric Tietz, Christiane K. Kuhl, Kerstin Fehrenbacher, Andreas NappRationale and ObjectivesTo identify the influence and artifact burden in cardiac CT imaging of a leadless cardiac pacemaker (LCP) performed with all three generations of DualSource CT (DSCT) Scanners.Materials and MethodsThe LCP was examined in DSCT scanners of the first to third generation using DualEnergy (DECT) and DSCT as well as alterations of the current-time product. For DECT examinations, virtual monoenergetic images were computed manually on a dedicated workstation. Virtual voltage was manually selected by subjective assessment of the lowest artifact burden. Systematic variations of the pacemaker angle to the gantry were assessed, too. The angle was successively increased by 10°, ranging from 0° to 90°. Artifact burden was quantified on a five-point Likert scale (1- no artifacts, 2- few artifacts, 3- moderate artifacts, 4- many artifacts, and 5- massive artifacts). Likert values of 1–3 were considered diagnostic and assessed by two board-certified radiologists in consensus.ResultsIn total, 200 examinations were analyzed, a mean Likert value of 1.93 ± 0.61 was found overall. None of the images were assessed Likert value>3. The positioning evaluation showed a clear and significant reduction of artifact burden toward lower angles, (0°: 1.4 ± 0.5 vs. 90° 2.55 ± 0.51). At scanner level, second-generation DSCT performed significantly better (1.68 ± 0.47) than both other scanners. Comparison of technique (DECT vs. DSCT) revealed a significantly improved image quality in DSCT examinations.ConclusionLCP can be safely examined in DSCT scanner of the first to third generation with the evaluated protocols and techniques, which are currently in use. Artifact burden can be significantly reduced by aligning or approaching the LCP's longitudinal axis toward the scanner's z-axis.
       
  • Social Media and Radiology Education: Are We #Ready'
    • Abstract: Publication date: Available online 6 November 2018Source: Academic RadiologyAuthor(s): Joshua P NickersonSocial media has become integrated into the lives of millions of people, but it has only recently been explored as a potential teaching tool. There is a body of literature to suggest that today's learners desire use of these interactive platforms for learning and that they result in higher degrees of student satisfaction, although it is not yet clear that a greater degree of knowledge transfer or retention is achieved. There are barriers to implementation in a curriculum, but as we learn to overcome these barriers and find new and creative ways to leverage social media we as educators will meet our students needs in the era of “web 2.0” and the digital native generation.
       
  • Innovative Teaching Methods in Radiology—Building on the Experiences
           of Other Disciplines
    • Abstract: Publication date: Available online 3 November 2018Source: Academic RadiologyAuthor(s): Jonathan L. Mezrich
       
  • Conventional MR-based Preoperative Nomograms for Prediction of IDH/1p19q
           Subtype in Low-Grade Glioma
    • Abstract: Publication date: Available online 2 November 2018Source: Academic RadiologyAuthor(s): Zhenyin Liu, Tao Zhang, Hua Jiang, Wenchan Xu, Jing ZhangRationale and ObjectivesTo develop nomogram models incorporating MR and clinical features for preoperative prediction of isocitrate dehydrogenase (IDH)/1p19q subtype in patients with lower-grade gliomas (LGG).Materials and methodsWe classified LGG (149 patients) into three categories: (1) IDH mutation and 1p/19q codeletion, (2) IDH mutation and no 1p/19q codeletion, and (3) wild-type IDH. The correlation between clinical and MR features and IDH/1p19q subtype was analyzed.Results(1) Multivariate analysis showed that hemorrhage (yes vs no odds ratio [OR]: 12.775), enhancing margin (poorly vs well defined OR: 17.87), and SVZ (SVZ+ vs SVZ− OR: 0.304 were associated with a higher incidence of IDHmut-codel status (All p < 0.05). (2) Multivariate analysis showed that age (≥40 years vs 60 cm3 vs ≤60 cm3 OR: 5.111), and the shortest distance from the tumor centroid to the edge of the lateral ventricles (CS) (>30 mm vs ≤30 mm OR: 3.766) were associated with a higher incidence of IDHmut-noncodel status. (3) Multivariate analysis showed age (≥40 years vs 60 cm3 vs ≤60 cm3 OR: 0.188), CS (>30 mm vs ≤30 mm OR: 0.285), necrosis (yes vs no OR: 0.193), and proportion CE tumor (>5% vs ≤5% OR: 5.253) were associated with a higher incidence of IDHwt status. Three nomogram models showed good discrimination (all area under the curve> 0.8) and calibration.ConclusionClinical and MR features may therefore be used to facilitate the preoperative prediction of LGG IDH/1p19q subtype.
       
  • Quantification of Degree of Liver Fibrosis Using Fibrosis Area Fraction
           Based on Statistical Chi-Square Analysis of Heterogeneity of Liver Tissue
           Texture on Routine Ultrasound Images
    • Abstract: Publication date: Available online 2 November 2018Source: Academic RadiologyAuthor(s): Janelle Li, Mustafa Qureshi, Avneesh Gupta, Stephan W. Anderson, Jorge Soto, Baojun LiRationale and ObjectivesWe present a novel method to quantify the degree of liver fibrosis using fibrosis area fraction based on statistical chi-square analysis of heterogeneity of echo texture within liver on routine ultrasound images. We demonstrate, in a clinical study, that fibrosis area fraction derived this way has the potential to become a noninvasive, quantitative radiometric discriminator of normal or low-grade liver fibrosis (Ishak fibrosis score range = F0–3) and advanced liver fibrosis or cirrhosis (Ishak fibrosis score range = F4–6) on routine ultrasound images.Materials and MethodsThis retrospective patient study was institutional review board approved. Ultrasound images of 100 patients (61 males, 39 females; 18–81 years) who underwent nontargeted ultrasound-guided biopsy were randomly divided into two groups: a training group consisted of 31 cases, and a validation group that contained the rest cases. An investigator manually selected a primary region of interest (ROI; approximately 4–6 cm2) in the liver tissue while avoiding nonhepatic parenchyma. The primary ROI contained a large number of secondary ROIs (25 × 25 pixels) to maintain the precision of statistical analysis. Sample variance σ2 of image gradient (a texture feature related to the amount of edge structures) was calculated in secondary ROIs in a roster scan fashion. A theoretical derivation was presented to estimate population variance σ02~ of image gradient across the primary ROI from mean gradient µ of secondary ROIs. The χ2 (χ2 = σ2/σ02~) was computed at each secondary ROI, forming a χ2 map of liver tissue heterogeneity. A cut-off value was optimized from datasets in the training group by comparing to the fibrosis grades determined by biopsy. This cut-off value was then applied to the datasets in the validation group to convert the χ2 maps into binary images, from which fibrosis area fractions (fraction of fibrosis area to the total area of the primary ROI) were calculated and entered in a statistical analysis.ResultsIn the training group, the optimal setting was found to be Tχ2= 6.0, which resulted a maximum discrimination of F0–3 vs F4–6: p < 0.0001, area under curve = 0.985, sensitivity = 93.7%, specificity = 93.3%. When this setting was applied to the datasets in the validation group, a distinct separation was seen between the two classes (p < 0.0001). F0–3 class had an average fibrosis area fraction of 4.7% (1.7%−11.4%), whereas the F4–6 class had an average fibrosis area fraction of 17.3% (9.8%−29.6%). A strong correlation was demonstrated between the fibrosis area fraction and histological fibrosis grade determined by biopsy (area under curve = 0.89, sensitivity = 87.9%, specificity = 90.3%).ConclusionThe presented method is a promising noninvasive tool for distinguishing normal or low-grade liver fibrosis (F0–3) and advanced liver fibrosis or cirrhosis (F4–6) from routine ultrasound images. These findings support the further development of texture heterogeneity analysis, particularly fibrosis area fraction, as a quantitative biomarker for distinguishing various liver fibrosis grades.
       
  • Letter to the Editor Regarding Survey Research: A Primer for the Academic
           Radiologist
    • Abstract: Publication date: Available online 31 October 2018Source: Academic RadiologyAuthor(s): Christopher M. Straus, Andrew W Phillips
       
  • The Value of IVIM DWI in Combination with Conventional MRI in Identifying
           the Residual Tumor After Cone Biopsy for Early Cervical Carcinoma
    • Abstract: Publication date: Available online 30 October 2018Source: Academic RadiologyAuthor(s): Junqi Sun, Guangyao Wu, Feifei Shan, Zhihua MengRationale and ObjectivesTo investigate the value of intravoxel incoherent motion (IVIM) diffusion-weighted imaging (DWI) in combination with conventional MRI in identifying the residual tumor after biopsy for early cervical carcinoma.Materials and MethodsEighty patients with histologically proven early cervical carcinoma were enrolled into this study. MRI sequences included two sets of MRI sequences including conventional MRI (T1WI, T2WI, and dynamic contrast-enhanced MRI) and IVIM DWI/conventional MRI combinations. The patients were classified into residual tumor and nonresidual tumor group after biopsy. IVIM parameters were quantitatively analyzed and compared between two groups. The diagnostic ability of two sets of MRI sequences were calculated and compared.ResultsThe mean D and f values were significantly lower in residual tumor group than in nonresidual tumor group (p < 0.05). The areas under receiver operating characteristic curves of D and f for discriminating between residual tumor and nonresidual tumor group were 0.848 and 0.767, respectively. The sensitivity and accuracy of conventional MRI/IVIM DWI combinations for the detection of residual tumor were 82.7% and 83.8%, respectively, while the sensitivity and accuracy of conventional MRI were 52.4% and 53.8%, respectively.ConclusionThe addition of IVIM DWI to conventional MRI considerably improves the sensitivity and accuracy of the detection of residual tumor after biopsy for early cervical carcinoma.
       
  • Evaluation of Tumor Hypoxia in C6 Glioma Rat Model With Dynamic
           Contrast-Enhanced Magnetic Resonance Imaging
    • Abstract: Publication date: Available online 30 October 2018Source: Academic RadiologyAuthor(s): Weishu Hou, Yangyang Xue, Wei Tang, Hongli pan, Man Xu, Xiaohu Li, Sixing Bi, Yujun Shen, Yinfeng Qian, Yongqiang YuRationale and ObjectivesTo investigate the feasibility of determining quantitative parameters for evaluating tumor hypoxia in the C6 glioma model by dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI).Materials and methodsThirty male Sprague-Dawley rats were inoculated to establish C6 brain glioma models. DCE-MRI scans were performed 14, 21, and 28 days after transplantation. Quantitative parameters comprising Ktrans, Ve, Kep, and Vp were calculated and analyzed. At the end of each scan, 10 rats were randomly selected for immunohistochemical (IHC) staining of hypoxia-inducible factor-17αl (HIF-1α), proliferating cell nuclear antigen (PCNA), and CD34. Correlations between quantitative parameters and IHC scores were analyzed.ResultsThe tumor volumes increased with time. The Ktrans values on days 14, 21, and 28 were 0.03 ± 0.009 min−1, 0.084 ± 0.010 min−1, and 0.050 ± 0.016 min−1, while the Ve values were 0.17 ± 0.070, 0.46 ± 0.159, and 0.51 ± 0.193, the Kep values were 0.18 ± 0.070%, 0.220 ± 0.049%, and 0.06 ± 0.035%, and these three parameters all differed significantly among the three time points. The Vp values on days 14, 21, and 28 were 0.09 ± 0.040%, 0.120 ± 0.034%, and 0.06 ± 0.010%, but the values did not differ among the three time points (P = 0.073). Ktrans had significant negative correlations with the HIF-1α scores on days 14 and 21 when there was also a positive correlation between Ktrans and CD34. Ve had negative correlations with the HIF-1α score on days 14 and 21, and there was a negative correlation between Ve and PCNA on day 21. Kep had a negative correlation with the HIF-1α score and a positive correlation with MVD on day 21.ConclusionsDCE-MRI may be a useful method for the noninvasive evaluation of the hypoxia status in a glioma model.
       
  • Clinical Decision Support for Ordering CTA-PE Studies in the Emergency
           Department—A Pilot on Feasibility and Clinical Impact in a Tertiary
           Medical Center
    • Abstract: Publication date: Available online 30 October 2018Source: Academic RadiologyAuthor(s): Alexander Goehler, Christopher Moore, Jennifer M Manne-Goehler, Jennifer Arango, Linda D'Amato, Howard P Forman, Jeffrey WeinrebPurposeTo determine the feasibility and impact of Clinical Decision Support for imaging ordering.MethodsA survey of 231 emergency providers identified Computed tomography angiography (CTA)-Pulmonary embolism (PE) as an overutilized study. We developed an algorithm that combined established risk scores to stratify patients for PE work-up (recommendations: CTA, D-dimer or no further testing); the algorithm was integrated into the Epic Radiology Information Ordering System.ResultsAmong 872 studies requested, 479 (55%) received a recommendation to change their order: 6 (1.3%) were cancelled; 13 (2.7%) changed to a D-dimer, and 460 (96%) proceeded with CTA. Of the 853 studies conducted, 8.2% were positive for PE. The algorithm had good discriminatory power with positivity rates of 12.0% (CT), 10.0% (D-dimer), and 2.6% (no further testing). Compliance with the recommendation ranged from 12%–68% (mean 45%) with 10% correlation between compliance and positivity rates.ConclusionWhile the CDS algorithm was accurate, it had only a minimal impact on ordering practices, in part due to heterogeneity in physician adherence.
       
  • The Association Between Bronchial Wall CT Attenuation and Spirometry in
           Patients with Bronchial Asthma
    • Abstract: Publication date: Available online 28 October 2018Source: Academic RadiologyAuthor(s): Shoichiro Matsushita, Tsuneo Yamashiro, Shin Matsuoka, Kunihiro Yagihashi, Yasuo NakajimaRationale and ObjectiveThe purpose of this study was to evaluate the correlation between generation-based bronchial wall attenuation on thin-section computed tomography (CT) scans and airflow limitation in patients with bronchial asthma.Materials and MethodsThis study included 28 bronchial asthma patients (13 men, 15 women; age range, 23–89 years) who underwent both chest CT and spirometry. On CT, the mean values of peak wall attenuation, wall area percentage, and luminal area were measured in the segmental, subsegmental, and sub-subsegmental bronchi of the right B1 and B10 bronchi. Correlations of the CT measurements with forced expiratory volume in 1 second/forced vital capacity (FEV1/FVC), percent predicted forced expiratory flow at 25%–75% of the FVC (%pred forced expiratory flow25–75), and percent predicted peak flow rate were evaluated with Spearman's rank correlation test.ResultsThe peak wall attenuation of each generation of segmental bronchi significantly correlated with the forced expiratory volume in 1 second/FVC (B1 segmental, ρ = −0.683, p < 0.0001; B1 subsegmental, ρ = −0.875, p < 0.0001; B1 sub-subsegmental, ρ = −0.926, p < 0.0001; B10 segmental, ρ = −0.811, p < 0.0001; B10 subsegmental, ρ = −0.903, p < 0.0001; B10 sub-subsegmental ρ = −0.950, p < 0.0001). Similar correlations were found between the peak wall attenuation and %pred forced expiratory flow25–75 or percent predicted peak flow rate. Overall, the correlation coefficients were relatively high in the more peripheral bronchial generations. In all measurements, the coefficients of the peak wall attenuations were higher than those of the wall area percentage and luminal area.ConclusionPeak attenuation of the bronchial wall, particularly in the peripheral bronchi, measured on CT is a good biomarker for the severity of bronchial asthma.
       
  • Soft Tissue Sarcomas: Preoperative Predictive Histopathological Grading
           Based on Radiomics of MRI
    • Abstract: Publication date: Available online 28 October 2018Source: Academic RadiologyAuthor(s): Yu Zhang, Yifeng Zhu, Xiaomeng Shi, Juan Tao, Jingjing Cui, Yue Dai, Minting Zheng, Shaowu WangRationale and ObjectivesThe purpose of this study is to develop a radiomics model for predicting the histopathological grades of soft tissue sarcomas preoperatively through magnetic resonance imaging (MRI).Materials and MethodsThirty-five patients who were pathologically diagnosed with soft tissue sarcomas and their histological grades were recruited. All patients had undergone MRI before surgery on a 3.0T MRI scanner. Radiomics features were extracted from fat-suppressed T2-weighted imaging. We used the least absolute shrinkage and selection operator (LASSO) regression method to select features. Then three machine learning classification methods, including random forests, k-nearest neighbor, and support vector machine algorithm were trained using the 5-fold cross validation strategy to separate the soft tissue sarcomas with low- and high-histopathological grades.ResultsThe radiomics features were significantly associated with the histopathological grades. Quantitative imaging features (n = 1049) were extracted from fat-suppressed T2-weighted imaging, and five features were selected to construct the radiomics model. The model that used support vector machine classification method achieved the best performance among the three methods, with areas under the receiver operating characteristic curves Area Under Curve (AUC) values of 0.92 ± 0.07, accuracy of 0.88.ConclusionGood accuracy and AUC could be obtained using only five radiomic features. Therefore, we proposed that three-dimensional imaging features from fat-suppressed T2-weighted imaging could be used as candidate biomarkers for preoperative prediction of histopathological grades of soft tissue sarcomas noninvasively.
       
  • Optimizing the Learning and Working Environment for Radiology Residents
    • Abstract: Publication date: Available online 27 October 2018Source: Academic RadiologyAuthor(s): Seth Stalcup, Rebecca Leddy, Jeanne Hill, Madelene LewisRationale and Objectives: In the newest revision of the Accreditation Council for Graduate Medical Education Common Program Requirements, substantial changes were made to section VI now entitled “The Learning and Working Environment.”The Accreditation Council for Graduate Medical Education expanded section VI to include patient safety, quality improvement, supervision, accountability, well-being, and fatigue mitigation realizing work hours represent only one part of the work environment.Materials and Methods: These new requirements prompted us to evaluate our current curriculum, including our current tools for meeting program requirements such as the didactic lecture series and tracking resident progress in our Clinical Competency Committee, and identified areas of our curriculum that were lacking or could be improved upon.Results: This assessment leads to incorporation of innovative and novel strategies to not only satisfy the requirements but also to engage our trainees throughout the process.Conclusion: Our model can be used as an example for other residency programs looking for ways to fulfill these new requirements.
       
  • Image Quality Performance of Virtual Single-Source CT Using Dual-Source
           Computed Tomography
    • Abstract: Publication date: Available online 25 October 2018Source: Academic RadiologyAuthor(s): Babak Alikhani, Martin Werner, Leila Jamali, Frank Wacker, Thomas WernckeRationale and ObjectivesThe aim of this study is to analyze the image quality provided by a dual-source (DS) data set and a single-source (SS) data set at the same radiation exposure, in order to evaluate a dose splitting method for dual-source scanning protocols.Materials and MethodsA 192-slice dual-source third generation CT (Somatom Force; Siemens Healthcare, Forchheim, Germany) was used to image a Catphan phantom (Catphan503; The Phantom Laboratory, Salem, New York) utilizing different X-ray tube voltages from 70 to 120 kVp with an organ-based tube-current modulation technique (X-CARE; Siemens Healthcare, Forchheim, Germany). In order to keep the radiation dose (given by volume computed tomography dose index) in a clinically relevant range, different X-ray tube time-current products ranging from 80 to 300 mAs were selected. The data sets by each X-ray tube voltage were collected using a single-source as well as a dual-source mode. The measurements in the dual-source mode were performed with five different tube currents of the X-ray tube A and B. Thereby, the tube current ratios were 50% 50% (DS 0.5), 60% 40% (DS 0.6), 70% 30% (DS 0.7), 80% 20% (DS 0.8), and 90% 10% (DS 0.9). The images were reconstructed by the use of a filter-back projection (Br40) and an advanced mode led iterative reconstruction algorithms (advanced modeled iterative reconstruction algorithms [ADMIRE]; Siemens Healthcare, Forchheim, Germany) with a strength range of 1–5. The image quality was evaluated in terms of noise, contrast-to-noise ratio (CNR), low-contrast detectability expressed as the structural similarity index (SSIM) and spatial resolution quantified by the full width at half maximum of the line-spread function.ResultsImage noise decreased by the use of the dual-source mode, which led to improvement of their CNR compared to the single-source mode. SSIM showed an almost constant behavior by both modes. The spatial resolution indicated a lower trend by the dual-source mode in comparison to the single-source mode. However, the loss of the spatial resolution performance was lower than 5% for the dual-source modes.ConclusionThe presented phantom study demonstrated that SSIM and spatial resolution performance obtained by dual-source CT protocols showed a negligible variation to those by the single-source CT. However, the noise and CNR displayed an improvement for the dual-source CT. Therefore, the use of the dual-source CT enables to split the radiation dose between X-ray tubes and to compare the data sets with different radiation dose levels without loss in the image quality.
       
  • Dose Optimization of Perfusion-derived Response Assessment in
           Hepatocellular Carcinoma Treated with Transarterial Chemoembolization:
           Comparison of Volume Perfusion CT and Iodine Concentration
    • Abstract: Publication date: Available online 25 October 2018Source: Academic RadiologyAuthor(s): Wolfgang M. Thaiss, Ulrike Haberland, Sascha Kaufmann, Tobias Hepp, Maximilian Schulze, Anya C. Blum, Dominik Ketelsen, Konstantin Nikolaou, Marius Horger, Alexander W. SauterRationale and ObjectivesWe assessed the value of iodine concentration (IC) as a perfusion-derived response marker for hepatocellular carcinoma (HCC) treated with transarterial chemoembolization (TACE) in comparison with volume perfusion computed tomography (VPCT) parameters.Materials and MethodsForty-one HCC lesions in 32 patients examined before and after TACE were analyzed retrospectively. VPCT-parameters were calculated and lesion iodine-maps were computed using subtraction of the baseline and the scan 7 seconds after aortic peak enhancement from the corresponding 80 kVp-VPCT data set. Modified RECIST was used as standard response criteria. Comparisons were performed using Student's t test for normal distributed data and Mann–Whitney U test for non-normal distributed data. Additionally, correlation analysis, receiver operating characteristics (ROC) and interreader agreement were assessed.ResultsIn responding lesions, mean pre-TACE IC and blood flow (BF) were 131.2 mg/100 mL and 96.7 mL/100 mL/min, decreasing to IC 25.6 mg/100 mL (P < 0.001) and BF 28.5 mL/100 mL/min (P < 0.001) post-TACE. In nonresponding lesions, the values remained almost unchanged: pre-TACE: mean BF 79.3 mL/100 mL/min and mean IC 90.4 mg/100 mL; post-TACE: mean BF 71.3 mL/100 mL/min (n.s.) and mean IC 105.4 mg/100 mL (n.s.). Differences in IC-values revealed a high sensitivity/specificity of 96.7%/81.8%. IC and VPCT-parameters showed strong, positive correlations. Mean volume CT dose index for VPCT was 63.4 mGy and 4.9 mGy for iodine maps.ConclusionThus, IC is a meaningful perfusion marker for local therapy response monitoring in HCC that can be acquired with low radiation dose. This information is important for further therapy response applications using dual and single energy CT.
       
  • Productivity, Meet Burnout
    • Abstract: Publication date: Available online 24 October 2018Source: Academic RadiologyAuthor(s): Richard H. Cohan, Matthew S. Davenport
       
  • “Why We Need a Guide to New Teaching Methods Now”
    • Abstract: Publication date: Available online 19 October 2018Source: Academic RadiologyAuthor(s): Kitt Shaffer
       
  • Age-Related Declines in Occipital GABA are Associated with Reduced Fluid
           Processing Ability
    • Abstract: Publication date: Available online 14 October 2018Source: Academic RadiologyAuthor(s): Molly Simmonite, Joshua Carp, Bradley R. Foerster, Lynn Ossher, Myria Petrou, Daniel H. Weissman, Thad A. PolkRationale and ObjectivesHealthy aging is associated with pervasive declines in cognitive, motor, and sensory functioning. There are, however, substantial individual differences in behavioral performance among older adults. Several lines of animal research link age-related reductions of gamma-aminobutyric acid (GABA), the brain's primary inhibitory neurotransmitter, to age-related cognitive, motor, and sensory decline. Our study used proton magnetic resonance spectroscopy (MRS) at 3T to explore whether occipital GABA declines with age in humans and whether individual differences in occipital GABA are linked to individual differences in fluid processing ability.Materials and MethodsWe used a MEGA-PRESS sequence that combines frequency spectral editing with a point-resolved spectroscopy sequence to quantify GABA. Spectra were obtained from a 30 × 30 × 25mm voxel placed in the occipital cortex of 20 young adults (mean age 20.7 years) and 18 older adults (mean age 76.5 years). Participants also performed 11 fluid processing tasks outside the scanner, the results of which were z-scored and averaged to calculate a summary measure of fluid processing ability. Regression analysis was employed to determine the relationship between GABA concentrations in the occipital cortex and a summary measure of fluid processing ability.ResultsOccipital GABA was significantly lower in older participants compared to the younger participants. We also observed a significant positive relationship between occipital GABA and fluid processing ability. In fact, higher GABA was associated with better task performance in 10 of the 11 tasks.ConclusionThese findings suggest that GABA levels decline with age in humans and are associated with declines in fluid processing ability.
       
  • The Diffusion Tensor Imaging Properties of the Normal Testicles at 3 Tesla
           Magnetic Resonance Imaging
    • Abstract: Publication date: Available online 13 October 2018Source: Academic RadiologyAuthor(s): Noam Nissan, Debbie Anaby, Ido Tavor, Yeruham Kleinbaum, Zohar Dotan, Eli Konen, Orith PortnoyRationale and ObjectivesThe testicles are structured in a well-defined microtubular network formation, which is expected to be reflected in high anisotropic diffusivity. However, preliminary studies reported on low values of fractional-anisotropy (FA) in the normal testicles. Our aim was to design and apply a diffusion-tensor imaging (DTI) protocol in order to elucidate the diffusivity properties of the testicles and their determining factors.Materials and Methods16 healthy volunteers were prospectively scanned at 3T. The protocol included T2-weighted and DTI sequences, the latter using 24 directional diffusion gradients and 3 b-values (0, 100, and 700 s/mm2) that were separated for analysis based on the reference b-value of 0 or 100 s/mm2. Image processing of the two DTI datasets yielded the diffusion vector maps and parametric maps of their corresponding principal diffusion coefficients λ1, λ2, λ3, mean diffusivity and FA.ResultsThe results demonstrated the feasibility of DTI to provide parametric maps of the testicles. The diffusion tensor parameters obtained using the pair of 0 and 700 s/mm2 b-values, exhibited relatively low diffusivity, with mean λ1 values of 1.36 ± 0.21 × 10−3 mm2/s and low anisotropy, with mean FA values of 0.13 ± 0.05. Analysis of DTI using the 100 and 700 s/mm2 b-values yielded a slight decrease in the diffusivity of 4%–5%, whereas FA remained similar.ConclusionThe diffusivity of the normal testicles is relatively slow, closed-to isotropic and hardly affected by the low b-values regime exclusion. Thus, DTI parameters of the normal testicles are neither dictated by the underlying architectural anisotropy nor microperfusion effects.
       
  • Radiologic and Pathologic Features Associated With Upgrade of Atypical
           Ductal Hyperplasia at Surgical Excision
    • Abstract: Publication date: Available online 12 October 2018Source: Academic RadiologyAuthor(s): Kristin E. Williams, Amanda Amin, Jacqueline Hill, Carissa Walter, Marc Inciardi, Jason Gatewood, Mark Redick, Jo Wick, Suzanne Hunt, Onalisa WinbladRationale and ObjectivesTo evaluate radiologic and pathologic features associated with upgrade of atypical ductal hyperplasia (ADH) to ductal carcinoma in situ or invasive breast cancer at surgical excision, in order to identify patients who may consider alternatives to excision.Materials and MethodsThis retrospective analysis examined patients who underwent surgical excision of biopsy-proven ADH at our institution. Imaging and pathology from biopsy were reviewed to determine radiologic (lesion size, radiologic abnormality, biopsy type, needle gauge, number of cores, percent of lesion removed) and pathologic features (histologic calcifications, presence of necrosis, micropapillary features, extent of ADH) associated with ADH upgrade.ResultsOne hundred twenty four cases of percutaneous biopsy-proven ADH with subsequent excision were included. The overall upgrade rate was 17.7% (n = 22), with 17 cases to ductal carcinoma in situ and five to invasive cancer. Radiologic features associated with a lower upgrade rate were smaller lesion size (p = 0.032) and larger percent of lesion removed at biopsy (p = 0.047). Larger needle gauge at biopsy (p = 0.070), absence of necrosis (p = 0.051) and focal ADH (
       
  • Utility of 13N-Ammonia PET/CT to Detect Pituitary Tissue in Patients with
           Pituitary Adenomas
    • Abstract: Publication date: Available online 12 October 2018Source: Academic RadiologyAuthor(s): Zongming Wang, Zhigang Mao, Xiangsong Zhang, Dongsheng He, Xin Wang, Qiu Du, Zheng Xiao, Diming Zhu, Yonghong Zhu, Haijun WangRationale and ObjectivesIt is clinically essential, but sometimes challenging, to distinguish pituitary tissue from pituitary adenomas (PAs). It is helpful to avoid damage of pituitary tissue during management. We evaluated the ability of 13N-ammonia positron emission tomography (PET)/computed tomography (CT) to locate and distinguish pituitary tissue from PAs.Materials and MethodsForty-eight patients (four with prolactinoma, 10 with Cushing's disease, 12 with acromegaly, and 22 with nonfunctional PAs) prospectively underwent magnetic resonance imaging (MRI), 13N-ammonia PET/CT, 18F-FDG PET/CT, prior to surgery.ResultsPituitary position could be determined in 31 (64.5%) patients by 13N-ammonia PET/CT, and by MRI in 26 (54.2%) patients. It was detected by 13N-ammonia PET/CT and MRI in eight of eight patients (100%) with pituitary microadenoma, tumor maximum diameter (TMD)
       
  • Whole Lesion Histogram Analysis Derived From Morphological MRI Sequences
           Might be Able to Predict EGFR- and Her2-Expression in Cervical Cancer
    • Abstract: Publication date: Available online 11 October 2018Source: Academic RadiologyAuthor(s): Hans-Jonas Meyer, Gordian Hamerla, Anne Kathrin Höhn, Alexey SurovRationale and ObjectivesHistogram analysis is an imaging analysis in which a whole tumor can be assessed, and every voxel of a radiological image is issued into a histogram. Thereby, statistically information about tumor can be obtained. The purpose of the study was to analyze possible relationships between histogram parameters derived from conventional MRI sequences and several histopathological features in cervical squamous cell carcinomas.MethodsA total of 18 female patients (age range 32–79 years) with squamous cell cervical carcinoma were retrospectively enrolled into the study. In all cases, pelvic MRI with a clinically protocol was performed. Histogram analysis was performed as a whole lesion measurement, calculating several percentils, minimum, mean, median, mode, maximum, kurtosis, skewness, and entropy. Histopathological parameters included expression of epidermal-growth factor (EGFR), vascular endothelial growth factor, hypoxia-inducible factor 1-alpha, Her2, and Histone 3. Spearman's correlation coefficient was used to analyze associations between investigated parameters.ResultsSeveral pre- and postcontrast derived T1-weighted parameters correlated inversely with EGFR expression. For precontrast T1-weighted images, the strongest correlation was found for p90 (ρ = −0.77, p = 0.004). For postcontrast T1-weighted images, the strongest correlation was observed for minimum (ρ = −0.64, p = 0.021). Several parameters derived from T2-weighted images were statistically significant different between Her2-positive and Her2 negative tumors. Skewness had the best p-value ( p = 0.004).ConclusionsHistogram analysis parameters of T1-weighted and T2-weighted images reflect HER2 status and EGFR expression in cervical cancer. Histogram parameters cannot predict cell count, proliferation index, or angiogenesis related histopathological features.
       
  • Continued Validation of Ultrasound Guidance Targeting Tasks: Assessment of
           Internal Structure
    • Abstract: Publication date: Available online 11 October 2018Source: Academic RadiologyAuthor(s): J.F. Nitsche, S. Conrad, S. Hoopes, M. Carrel, K. Bebeau, B.C. BrostRationale and ObjectivesWe previously demonstrated validity evidence for our novel ultrasound-guided invasive procedure targeting tasks in the content, response process, relations with other variables, and consequences validity domains. Here, we investigate their internal structure by assessing their interrater, intrarater, and test–retest reliability.MethodsIn thisInstitutional Review Board approved nonrandomized interventional trial first year medical students performed our previously described dowel and straw ultrasound guidance targeting tasks as a pretest. Afterward, the training group had four weekly 1-hour training sessions. The control group had no further training. Both groups then had a posttest for both tasks. The training group was re-evaluated 2 and 5 months later. Completion time in seconds, errors, and error adjusted time (5 seconds penalty/error) were recorded. Pretest and posttest performance was compared within groups, and the amount of improvement from pretest to posttest was compared between groups. Interrater, intrarater, and test–retest interclass correlation coefficients (ICC) were calculated.ResultsAlthough some improvements from pretest to posttest were seen in both groups, greater improvements were seen in the training group. This skill was retained for at least several months. The interrater and intrarater ICCs were excellent (range 0.83–0.93). The test–retest ICCs were good to excellent in all but one performance measure (0.50–0.78).ConclusionStudent performance on the targeting tasks improved markedly after training and persisted for several months. The interrater and intrarater reliability were excellent, while the test–retest reliability was good. This provides additional validity evidence for our novel ultrasound-guided invasive procedure targeting curriculum.
       
  • Response to: Letter to the Editor Regarding Survey Research: A Primer for
           the Academic Radiologist
    • Abstract: Publication date: Available online 11 October 2018Source: Academic RadiologyAuthor(s): Prasad R Shankar, Katherine E Maturen
       
  • Automated Test-Item Generation System for Retrieval Practice in Radiology
           Education
    • Abstract: Publication date: Available online 10 October 2018Source: Academic RadiologyAuthor(s): Gowthaman Gunabushanam, Caroline R. Taylor, Mahan Mathur, Jamal Bokhari, Leslie M. ScouttObjectiveTo develop and disseminate an automated item generation (AIG) system for retrieval practice (self-testing) in radiology and to obtain trainee feedback on its educational utility.Materials and MethodsAn AIG software program (Radmatic) that is capable of generating large numbers of distinct multiple-choice self-testing items from a given “item-model” was created. Instead of writing multiple individual self-testing items, an educator creates an “item-model” for one of two distinct item styles: true/false knowledge based items and image-based items. The software program then uses the item model to generate self-testing items upon trainee request. This internet-based system was made available to all radiology residents at our institution in conjunction with our didactic conferences. After obtaining institutional review board approval and informed consent, a written survey was conducted to obtain trainee feedback.ResultsTwo faculty members with no computer programming experience were able to create item-models using a standard template. Twenty five of 54 (46%) radiology residents at our institution participated in the study. Twelve of these 25 (48%) study participants reported using the self-testing items regularly, which correlated well with the anonymous website usage statistics. The residents’ overall impression and satisfaction with the self-testing items was quite positive, with a score of 7.89 ± 1.91 (mean ± SD) out of 10. Lack of time and email overload were the main reasons provided by residents for not using self-testing items.ConclusionAIG enabled self-testing is technically feasible, and is perceived positively by radiology residents as useful to their education.
       
  • Influence of Data Parsing on Contrast Enhanced Ultrasound Exams
    • Abstract: Publication date: Available online 10 October 2018Source: Academic RadiologyAuthor(s): Jingzhi Li, Laurence Needleman, Ji-Bin Liu, Andrej Lyshchik, Flemming Forsberg, Maria Stanczak, James McAlister, John EisenbreyRationale and ObjectivesTo explore the influence of data parsing (either selection of frames at set time intervals or by an experienced sonographer) of contrast-enhanced ultrasound (CEUS) exams on physician diagnoses and confidence levels.Materials and MethodsForty consecutive CEUS exams consisting of 10 cases each of indeterminate liver lesions, indeterminate renal lesions, renal cell carcinoma postablation follow-up, and hepatocellular carcinoma postchemoembolization follow-up were selected for analysis. Exams were parsed into sets consisting of five images selected by the performing sonographer and sets containing systematically stored frames every 10, 30, and 60 seconds. Three blinded physicians then reviewed the cine loop and each set of images in randomized order and provided a diagnosis and confidence level.ResultsFor all clinical applications investigated, no statistically significant differences in diagnostic performance measures or reader confidence were observed between review of the entire cine loop and images selected by the performing sonographer (p> 0.42). Diagnostic performance at 10-second intervals did not show statically significant changes compared to the full cine loop review for all applications (p> 0.18), although reader confidence decreased. At 30–60-second intervals, both diagnostic performance and reader confidence showed statistically significant reduction compared to review of the full cine loop (p < 0.045).ConclusionsTransfer and review of large cine loops from CEUS exams represent a potential barrier to adoption within the United States workflows. This study demonstrates that images selected by a performing trained sonographer may provide the same value without the review time and data storage costs needed for full cine loop review. Parsing by time points reduced reader confidence and diagnostic performance.
       
 
 
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