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Publisher: Elsevier   (Total: 3181 journals)

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Showing 1 - 200 of 3181 Journals sorted alphabetically
Academic Pediatrics     Hybrid Journal   (Followers: 39, SJR: 1.655, CiteScore: 2)
Academic Radiology     Hybrid Journal   (Followers: 26, SJR: 1.015, CiteScore: 2)
Accident Analysis & Prevention     Partially Free   (Followers: 105, SJR: 1.462, CiteScore: 3)
Accounting Forum     Hybrid Journal   (Followers: 28, SJR: 0.932, CiteScore: 2)
Accounting, Organizations and Society     Hybrid Journal   (Followers: 42, SJR: 1.771, CiteScore: 3)
Achievements in the Life Sciences     Open Access   (Followers: 7)
Acta Anaesthesiologica Taiwanica     Open Access   (Followers: 6)
Acta Astronautica     Hybrid Journal   (Followers: 443, SJR: 0.758, CiteScore: 2)
Acta Automatica Sinica     Full-text available via subscription   (Followers: 2)
Acta Biomaterialia     Hybrid Journal   (Followers: 30, SJR: 1.967, CiteScore: 7)
Acta Colombiana de Cuidado Intensivo     Full-text available via subscription   (Followers: 3)
Acta de Investigación Psicológica     Open Access   (Followers: 3)
Acta Ecologica Sinica     Open Access   (Followers: 11, SJR: 0.18, CiteScore: 1)
Acta Histochemica     Hybrid Journal   (Followers: 5, SJR: 0.661, CiteScore: 2)
Acta Materialia     Hybrid Journal   (Followers: 319, 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: 2, SJR: 0.307, CiteScore: 0)
Acta Pharmaceutica Sinica B     Open Access   (Followers: 2, SJR: 1.793, CiteScore: 6)
Acta Poética     Open Access   (Followers: 4, SJR: 0.101, CiteScore: 0)
Acta Psychologica     Hybrid Journal   (Followers: 26, 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: 7, SJR: 0.19, CiteScore: 0)
Actualites Pharmaceutiques Hospitalieres     Full-text available via subscription   (Followers: 3)
Acupuncture and Related Therapies     Hybrid Journal   (Followers: 8)
Acute Pain     Full-text available via subscription   (Followers: 15, SJR: 2.671, CiteScore: 5)
Ad Hoc Networks     Hybrid Journal   (Followers: 11, SJR: 0.53, CiteScore: 4)
Addictive Behaviors     Hybrid Journal   (Followers: 18, SJR: 1.29, CiteScore: 3)
Addictive Behaviors Reports     Open Access   (Followers: 9, SJR: 0.755, CiteScore: 2)
Additive Manufacturing     Hybrid Journal   (Followers: 11, SJR: 2.611, CiteScore: 8)
Additives for Polymers     Full-text available via subscription   (Followers: 23)
Advanced Drug Delivery Reviews     Hybrid Journal   (Followers: 187, SJR: 4.09, CiteScore: 13)
Advanced Engineering Informatics     Hybrid Journal   (Followers: 12, SJR: 1.167, CiteScore: 4)
Advanced Powder Technology     Hybrid Journal   (Followers: 17, SJR: 0.694, CiteScore: 3)
Advances in Accounting     Hybrid Journal   (Followers: 9, SJR: 0.277, CiteScore: 1)
Advances in Agronomy     Full-text available via subscription   (Followers: 17, SJR: 2.384, CiteScore: 5)
Advances in Anesthesia     Full-text available via subscription   (Followers: 30, 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: 12, SJR: 0.992, CiteScore: 1)
Advances in Applied Mechanics     Full-text available via subscription   (Followers: 12, 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: 15, 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: 34, 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: 5)
Advances in Cellular and Molecular Biology of Membranes and Organelles     Full-text available via subscription   (Followers: 14)
Advances in Chemical Engineering     Full-text available via subscription   (Followers: 29, SJR: 0.156, CiteScore: 1)
Advances in Child Development and Behavior     Full-text available via subscription   (Followers: 11, 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: 26, SJR: 1.562, CiteScore: 3)
Advances in Colloid and Interface Science     Full-text available via subscription   (Followers: 20, 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: 15)
Advances in Developmental Biology     Full-text available via subscription   (Followers: 13)
Advances in Digestive Medicine     Open Access   (Followers: 12)
Advances in DNA Sequence-Specific Agents     Full-text available via subscription   (Followers: 7)
Advances in Drug Research     Full-text available via subscription   (Followers: 26)
Advances in Ecological Research     Full-text available via subscription   (Followers: 44, SJR: 2.524, CiteScore: 4)
Advances in Engineering Software     Hybrid Journal   (Followers: 29, 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: 52, 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: 67, SJR: 0.591, CiteScore: 2)
Advances in Fuel Cells     Full-text available via subscription   (Followers: 17)
Advances in Genetics     Full-text available via subscription   (Followers: 21, SJR: 1.354, CiteScore: 4)
Advances in Genome Biology     Full-text available via subscription   (Followers: 11, SJR: 12.74, CiteScore: 13)
Advances in Geophysics     Full-text available via subscription   (Followers: 7, SJR: 1.193, CiteScore: 3)
Advances in Heat Transfer     Full-text available via subscription   (Followers: 26, SJR: 0.368, CiteScore: 1)
Advances in Heterocyclic Chemistry     Full-text available via subscription   (Followers: 11, SJR: 0.749, CiteScore: 3)
Advances in Human Factors/Ergonomics     Full-text available via subscription   (Followers: 26)
Advances in Imaging and Electron Physics     Full-text available via subscription   (Followers: 3, SJR: 0.193, CiteScore: 0)
Advances in Immunology     Full-text available via subscription   (Followers: 37, SJR: 4.433, CiteScore: 6)
Advances in Inorganic Chemistry     Full-text available via subscription   (Followers: 10, 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: 9, 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: 21, SJR: 0.88, CiteScore: 2)
Advances in Mathematics     Full-text available via subscription   (Followers: 15, SJR: 3.027, CiteScore: 2)
Advances in Medical Sciences     Hybrid Journal   (Followers: 8, SJR: 0.694, CiteScore: 2)
Advances in Medicinal Chemistry     Full-text available via subscription   (Followers: 6)
Advances in Microbial Physiology     Full-text available via subscription   (Followers: 5, SJR: 1.158, CiteScore: 3)
Advances in Molecular and Cell Biology     Full-text available via subscription   (Followers: 25)
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: 5)
Advances in Oncobiology     Full-text available via subscription   (Followers: 2)
Advances in Organ Biology     Full-text available via subscription   (Followers: 2)
Advances in Organometallic Chemistry     Full-text available via subscription   (Followers: 18, 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: 27, SJR: 0.461, CiteScore: 1)
Advances in Pharmaceutical Sciences     Full-text available via subscription   (Followers: 19)
Advances in Pharmacology     Full-text available via subscription   (Followers: 17, SJR: 1.536, CiteScore: 3)
Advances in Physical Organic Chemistry     Full-text available via subscription   (Followers: 9, 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: 6)
Advances in Porous Media     Full-text available via subscription   (Followers: 5)
Advances in Protein Chemistry     Full-text available via subscription   (Followers: 19)
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: 68)
Advances in Quantum Chemistry     Full-text available via subscription   (Followers: 6, SJR: 0.371, CiteScore: 1)
Advances in Radiation Oncology     Open Access   (Followers: 2, 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: 423, 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: 13, SJR: 0.555, CiteScore: 2)
Advances in the Study of Behavior     Full-text available via subscription   (Followers: 38, SJR: 2.208, CiteScore: 4)
Advances in Veterinary Medicine     Full-text available via subscription   (Followers: 20)
Advances in Veterinary Science and Comparative Medicine     Full-text available via subscription   (Followers: 15)
Advances in Virus Research     Full-text available via subscription   (Followers: 6, SJR: 2.262, CiteScore: 5)
Advances in Water Resources     Hybrid Journal   (Followers: 54, SJR: 1.551, CiteScore: 3)
Aeolian Research     Hybrid Journal   (Followers: 6, SJR: 1.117, CiteScore: 3)
Aerospace Science and Technology     Hybrid Journal   (Followers: 384, 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: 12, SJR: 3.671, CiteScore: 9)
Aggression and Violent Behavior     Hybrid Journal   (Followers: 482, SJR: 1.238, CiteScore: 3)
Agri Gene     Hybrid Journal   (Followers: 1, SJR: 0.13, CiteScore: 0)
Agricultural and Forest Meteorology     Hybrid Journal   (Followers: 18, SJR: 1.818, CiteScore: 5)
Agricultural Systems     Hybrid Journal   (Followers: 32, SJR: 1.156, CiteScore: 4)
Agricultural Water Management     Hybrid Journal   (Followers: 45, 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: 58, SJR: 1.747, CiteScore: 4)
Ain Shams Engineering J.     Open Access   (Followers: 5, SJR: 0.589, CiteScore: 3)
Air Medical J.     Hybrid Journal   (Followers: 8, SJR: 0.26, CiteScore: 0)
AKCE Intl. J. of Graphs and Combinatorics     Open Access   (SJR: 0.19, CiteScore: 0)
Alcohol     Hybrid Journal   (Followers: 12, SJR: 1.153, CiteScore: 3)
Alcoholism and Drug Addiction     Open Access   (Followers: 12)
Alergologia Polska : Polish J. of Allergology     Full-text available via subscription   (Followers: 1)
Alexandria Engineering J.     Open Access   (Followers: 2, 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: 11, SJR: 0.201, CiteScore: 1)
Alzheimer's & Dementia     Hybrid Journal   (Followers: 54, SJR: 4.66, CiteScore: 10)
Alzheimer's & Dementia: Diagnosis, Assessment & Disease Monitoring     Open Access   (Followers: 6, SJR: 1.796, CiteScore: 4)
Alzheimer's & Dementia: Translational Research & Clinical Interventions     Open Access   (Followers: 6, SJR: 1.108, CiteScore: 3)
Ambulatory Pediatrics     Hybrid Journal   (Followers: 5)
American Heart J.     Hybrid Journal   (Followers: 58, SJR: 3.267, CiteScore: 4)
American J. of Cardiology     Hybrid Journal   (Followers: 66, SJR: 1.93, CiteScore: 3)
American J. of Emergency Medicine     Hybrid Journal   (Followers: 47, SJR: 0.604, CiteScore: 1)
American J. of Geriatric Pharmacotherapy     Full-text available via subscription   (Followers: 13)
American J. of Geriatric Psychiatry     Hybrid Journal   (Followers: 14, SJR: 1.524, CiteScore: 3)
American J. of Human Genetics     Hybrid Journal   (Followers: 37, 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: 36, SJR: 2.973, CiteScore: 4)
American J. of Medicine     Hybrid Journal   (Followers: 50)
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: 265, 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: 32, 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: 39, 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: 67, SJR: 0.138, CiteScore: 0)
Anaesthesia Critical Care & Pain Medicine     Full-text available via subscription   (Followers: 25, SJR: 0.411, CiteScore: 1)
Anales de Cirugia Vascular     Full-text available via subscription   (Followers: 1)
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: 44, SJR: 1.512, CiteScore: 5)
Analytica Chimica Acta : X     Open Access  
Analytical Biochemistry     Hybrid Journal   (Followers: 210, SJR: 0.633, CiteScore: 2)
Analytical Chemistry Research     Open Access   (Followers: 13, SJR: 0.411, CiteScore: 2)
Analytical Spectroscopy Library     Full-text available via subscription   (Followers: 14)
Anesthésie & Réanimation     Full-text available via subscription   (Followers: 2)
Anesthesiology Clinics     Full-text available via subscription   (Followers: 25, 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: 227, SJR: 1.58, CiteScore: 3)
Animal Feed Science and Technology     Hybrid Journal   (Followers: 7, SJR: 0.937, CiteScore: 2)
Animal Reproduction Science     Hybrid Journal   (Followers: 7, SJR: 0.704, CiteScore: 2)

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Similar Journals
Journal Cover
Academic Radiology
Journal Prestige (SJR): 1.015
Citation Impact (citeScore): 2
Number of Followers: 26  
 
  Hybrid Journal Hybrid journal (It can contain Open Access articles)
ISSN (Print) 1076-6332
Published by Elsevier Homepage  [3181 journals]
  • Artificial Intelligence in Radiology––The State of the Future
    • Abstract: Publication date: Available online 18 November 2019Source: Academic RadiologyAuthor(s): Saurabh Jha, Tessa Cook
       
  • The Economics of Automation
    • Abstract: Publication date: Available online 18 November 2019Source: Academic RadiologyAuthor(s): Saurabh Jha
       
  • Automation and Radiology—Part 2
    • Abstract: Publication date: Available online 16 November 2019Source: Academic RadiologyAuthor(s): Saurabh Jha
       
  • Automation and Radiology—Part 1
    • Abstract: Publication date: Available online 16 November 2019Source: Academic RadiologyAuthor(s): Saurabh Jha
       
  • Value of Triage by Artificial Intelligence
    • Abstract: Publication date: Available online 16 November 2019Source: Academic RadiologyAuthor(s): Saurabh Jha
       
  • The Effect of Visual Hindsight Bias on Radiologist Perception
    • Abstract: Publication date: Available online 15 November 2019Source: Academic RadiologyAuthor(s): Jacky Chen, Stephen Littlefair, Roger Bourne, Warren M. ReedRationale and ObjectivesTo measure the effect of visual hindsight bias on radiologists’ perception during chest radiograph pulmonary nodule detection.Materials and MethodsThis was a prospective multi-observer study to assess the effect of hindsight bias on radiologists’ perception. Sixteen radiologists were asked to interpret 15 postero-anterior chest images containing a solitary lung nodule each consisting of 25 incremental levels of blur. Participants were requested initially to detect the nodule by reducing the blur of the images (foresight). They were then asked to increase the blur until the identified nodule was undetectable (hindsight). Participants then repeated the experiment, after being informed of the potential effects of hindsight bias and asked to counteract these effects. Participants were divided into two groups (experienced and less experienced) and the nodules were given different conspicuity ratings to determine the effect of expertise and task difficulty. Eye tracking technology was also utilised to capture visual search.ResultsWilcoxon analysis demonstrated significant differences between foresight and hindsight values of the radiologists (p = 0.02). However, after being informed of hindsight bias, these differences were no longer significant (p = 0.97). Friedman analysis also determined overall significance in the hindsight ratios between nodule conspicuities for both phases (phase 1: p = 0.02; phase 2: p = 0.02). There was no significance difference between the experienced and less experienced groups.ConclusionThis study demonstrated that radiologists exhibit hindsight bias but appeared to be able to compensate for this phenomenon once its effects were considered. Also, visual hindsight bias appears to be affected by task difficulty with a greater effect occurring with less conspicuous nodules.
       
  • Distinguishing Benign From Malignant Soft Tissue Tumors By Dynamic
           Susceptibility Contrast Magnetic Resonance Imaging
    • Abstract: Publication date: Available online 13 November 2019Source: Academic RadiologyAuthor(s): Masaaki Hori
       
  • Growth Assessment of Pulmonary Adenocarcinomas Manifesting as Subsolid
           Nodules on CT: Comparison of Diameter-Based and Volume Measurements
    • Abstract: Publication date: Available online 13 November 2019Source: Academic RadiologyAuthor(s): Constance de Margerie-Mellon, Ritu R. Gill, Antonio C. Monteiro Filho, Benedikt H. Heidinger, Allison Onken, Paul A. VanderLaan, Alexander A. BankierRationale and ObjectivesTo analyze the performances of diameter-based measurements, either using diameters, or by calculating diameter-based volumes, as compared to volume measurements in assessing growth of pulmonary adenocarcinomas manifesting as subsolid nodules on CT.Materials and MethodsIn this IRB-approved, retrospective study, 74 pulmonary adenocarcinomas presenting as subsolid nodules and resected in 69 patients (21 men, 48 women, mean age 70 ± 9 years) were included. Three CTs were available for each patient. Nodule size on each CT was assessed with diameter measurements, calculated volume based on diameter measurements, and measured volume. Nodule growth was defined as an increase of measured volume ≥25% between two sequential CTs. Sensitivity, specificity, accuracy, positive and negative predictive values of diameter-based measurements for growth assessment were calculated. Nodule characteristics were compared with nonparametric tests and analysis of variance.ResultsThere were fewer growing nodules during CT1-CT2 interval (n = 22, 30%) than during CT2-CT3 interval (n = 33, 45%, p =.060). Specificity and negative predictive value of diameter-based measurements for growth assessment ranged respectively from 52 to 77% and 81 to 83% between CT1 and CT2, and from 66 to 76% and 79 to 90% between CT2 and CT3. Nongrowing nodules tended to be larger, regardless how size was measured, and some of these differences in size were statistically significant (p =.002 to .046).ConclusionFor pulmonary adenocarcinomas presenting as subsolid nodules on CT, diameter-based assessment of nodule volume is reasonably accurate at confirming a lack of nodule growth but may overestimate actual growth, as compared to growth assessment based on measured volume.
       
  • Quantitative Evaluation of Intravoxel Incoherent Motion and Diffusion
           Kurtosis Imaging in Assessment of Pathological Grade of Clear Cell Renal
           Cell Carcinoma
    • Abstract: Publication date: Available online 11 November 2019Source: Academic RadiologyAuthor(s): Jing Ye, Qing Xu, Shou-An Wang, Jin Zheng, Wei-Qiang DouRationale and ObjectivesTo evaluate the diagnostic value of intravoxel incoherent motion and diffusion kurtosis imaging parameters for clear cell renal cell carcinoma (ccRCC) grading.Materials and MethodsA total of 60 patients with pathologically proven ccRCC who underwent intravoxel incoherent motion and diffusion kurtosis imaging were retrospectively evaluated. The standard apparent diffusion coefficient (ADC), true diffusivity (D), pseudo-diffusion coefficient (D*), perfusion fraction (f), mean kurtosis (MK), and mean diffusivity (MD) maps were calculated and compared between high-grade and low-grade ccRCC using Mann-Whitney U test. Receiver-operating characteristic analysis was performed for all parameters.ResultsADC, D and MD values were significantly lower for high-grade ccRCC compared to low-grade ccRCC (p < 0.05). MK values were significantly higher in high-grade ccRCC compared to low-grade ccRCC (p < 0.05). However, D* and f were not significantly difference between the two groups (p> 0.05). MD had the largest area under the curve (AUC = 0.888), followed by ADC (AUC = 0.796), D (AUC = 0.780), MK (AUC = 0.736), f (AUC = 0.582), and D*(AUC = 0.533).ConclusionDiffusion-related parameters (D, ADC, MD, and MK) were able to significantly distinguish between low- and high-grade ccRCC. However, perfusion-related parameters (D* and f) were unable to separate high- and low-grade ccRCC. MD may be the most promising parameter for grading ccRCC in the clinic.
       
  • Enthusiasm's Vital Role in Education
    • Abstract: Publication date: Available online 11 November 2019Source: Academic RadiologyAuthor(s): Giovanni D. Rodriguez, Richard B. Gunderman
       
  • Response: The USMLE Step 1 Pass/Fail Reporting Proposal: Another Opinion
    • Abstract: Publication date: Available online 11 November 2019Source: Academic RadiologyAuthor(s): Absia Jabbar, Shahzaib Nabi, Adeel Arshad, Muhammad Ali
       
  • Measurement Reliability and Diagnostic Accuracy of Virtual Monoenergetic
           Dual-Energy CT in Patients with Colorectal Liver Metastases
    • Abstract: Publication date: Available online 11 November 2019Source: Academic RadiologyAuthor(s): Lukas Lenga, Marvin Lange, Christophe T. Arendt, Christian Booz, Ibrahim Yel, Boris Bodelle, Tommaso D'Angelo, Renate M. Hammerstingl, Nicole A. Huizinga, Thomas J. Vogl, Simon S. Martin, Moritz H. AlbrechtRationale and ObjectivesTo compare dual-energy CT virtual monoenergetic images (VMI) and standard reconstructions for reliability of quantitative size measurements and diagnostic accuracy for the detection of colorectal liver metastases (CRLM).Materials and MethodsWe retrospectively included 98 patients (mean age, 61.1±11.5 years) with colorectal cancer, of whom 49 subjects had CRLM. All patients underwent a portal-venous phase dual-energy CT examination. Standard linearly-blended reformats and 40-keV VMI were reconstructed. For both reconstruction techniques, two blinded readers performed measurements of CRLM twice in a preset sequence. Three additional radiologists independently assessed all liver lesions in terms of dignity (benign vs. malignant). Sensitivity, specificity and diagnostic accuracy were calculated on a per-patient basis using MRI as reference standard. Readers scored the suitability for metric measurements and their diagnostic confidence using 5-point Likert scales. Inter-rater agreement was evaluated using intraclass correlation coefficient (ICC).ResultsInter-rater agreement for lesion size measurements was higher for 40-keV VMI (ICC, 0.88) compared to standard linearly-blended series (ICC, 0.80). Sensitivity and diagnostic accuracy for the detection of CRLM were significantly higher for VMI at 40-keV compared to standard reconstructions (90.6% vs. 80.6%, and 89.1% vs. 81.3%; p < 0.001). Reader scores indicated that 40-keV VMI were more suitable for metric lesion measurements and provided greater diagnostic confidence compared to standard reformats (median, 5 vs. 3, and 5 vs. 4; both p < 0.001).ConclusionLow-keV VMI reconstructions improve reliability of quantitative size measurements and diagnostic accuracy for the assessment of CRLM compared to standard linearly-blended images.
       
  • On High Grade Kidney Cancer and Machine Learning
    • Abstract: Publication date: Available online 9 November 2019Source: Academic RadiologyAuthor(s): Nicole E. Curci
       
  • Use of Digital Breast Tomosynthesis in Screening: Are Cancers as
           Conspicuous on Synthetic Mammograms as They Are on Full Field Digital
           Mammograms'
    • Abstract: Publication date: Available online 8 November 2019Source: Academic RadiologyAuthor(s): Claudia Mello-Thoms
       
  • Exploring Large-scale Public Medical Image Datasets
    • Abstract: Publication date: Available online 6 November 2019Source: Academic RadiologyAuthor(s): Luke Oakden-RaynerRationale and ObjectivesMedical artificial intelligence systems are dependent on well characterized large-scale datasets. Recently released public datasets have been of great interest to the field, but pose specific challenges due to the disconnect they cause between data generation and data usage, potentially limiting the utility of these datasets.Materials and MethodsWe visually explore two large public datasets, to determine how accurate the provided labels are and whether other subtle problems exist. The ChestXray14 dataset contains 112,120 frontal chest films, and the Musculoskeletal Radiology (MURA) dataset contains 40,561 upper limb radiographs. A subset of around 700 images from both datasets was reviewed by a board-certified radiologist, and the quality of the original labels was determined.ResultsThe ChestXray14 labels did not accurately reflect the visual content of the images, with positive predictive values mostly between 10% and 30% lower than the values presented in the original documentation. There were other significant problems, with examples of hidden stratification and label disambiguation failure. The MURA labels were more accurate, but the original normal/abnormal labels were inaccurate for the subset of cases with degenerative joint disease, with a sensitivity of 60% and a specificity of 82%.ConclusionVisual inspection of images is a necessary component of understanding large image datasets. We recommend that teams producing public datasets should perform this important quality control procedure and include a thorough description of their findings, along with an explanation of the data generating procedures and labeling rules, in the documentation for their datasets.
       
  • Correlation Between Radiology ACGME Case Logs Values and ABR Core Exam
           Pass Rate
    • Abstract: Publication date: Available online 4 November 2019Source: Academic RadiologyAuthor(s): Joshua P. Nickerson, Chris Koski, James C. Anderson, Brooke Beckett, Valerie P JacksonRationale and ObjectivesThere is discordance between the American Board of Radiology (ABR) and many radiology trainees with respect to the most appropriate means to prepare for the ABR Core Examination. Whereas the ABR suggests that participation in routine clinical examination interpretation best prepares a trainee for the practical material of the test, residents, and many program directors feel that time away from clinical service for study and review courses are necessary. This study examines the relationship between studies interpreted in the first three years of residency as reported in the Accreditation Council for Graduate Medical Education case logs and performance of first-time test takers on the ABR Core Examination.Materials and MethodsAccreditation Council for Graduate Medical Education case log data was anonymized for a single year cohort of residents in all accredited radiology residencies. This was then provided to the ABR and matched with performance on the Core Examination. A random effects logistic regression model was used to evaluate for a relationship between the number of examinations read and the pass/fail status of the Core Exam.ResultsModeling using a linear and a quadratic term yields a significant relationship between case log values and Core Exam performance. There is a positive correlation until an inflection point of approximately 11,000 examinations, at which point a negative correlation develops.ConclusionThe data supports that active engagement in clinical duties is associated with better performance on the ABR Core Examination, with the caveat that there appears to be a point at which service outweighs educational value. Beyond this, performance on the examination declines.
       
  • The Artificial Intelligence Journal Club (#RADAIJC): A Multi-Institutional
           Resident-Driven Web-Based Educational Initiative
    • Abstract: Publication date: Available online 2 November 2019Source: Academic RadiologyAuthor(s): Patricia Balthazar, Shahein H. Tajmir, Daniel A. Ortiz, Catherine C. Herse, Lindsey A.G. Shea, Kevin F. Seals, Dan Cohen-Addad, Saptarshi Purkayastha, Judy W. Gichoya
       
  • Brain Functional Alterations in Long-term Unilateral Hearing Impairment
    • Abstract: Publication date: Available online 31 October 2019Source: Academic RadiologyAuthor(s): Jianping Zhu, Jiangbo Cui, Gang Cao, Jianwu Ji, Xu Chang, Chongjie Zhang, Yongbo LiuBackgroundThe rate of patients with unilateral hearing impairments (UHI) increase with age and are characterized by asymmetric auditory afferents in which auditory information is asymmetrically transmitted to the brain. Long-term bilateral hearing imbalance can cause abnormal functional changes in the cerebral cortex. However, the relationship between functional alterations in the brain and the severity of the hearing impairment remains unclear.MethodsThis study included 33 patients with UHI (left-sided impairment in 17 and right-sided impairment in 16) and 32 healthy patients. All participants underwent resting-state, blood oxygen level dependent functional magnetic resonance imaging. Fractional amplitude of low frequency fluctuation (fALFF) values were calculated after data preprocessing and compared among the left-sided and right-sided impairment groups and the control group. Pure tone audiometry was used to evaluate patients’ hearing impairment level. The correlation between fALFF values of abnormal brain regions and the duration and severity of hearing impairment was analyzed.ResultsResults provide evidence for altered resting-state functional activities in the brain of patients with left or right long-term UHI, with significantly increased fALFF values in the Heschl's gyrus, superior temporal gyrus, and insula were observed. Moreover, complicated networks reorganization involved in the visual, cognitive, sensorimotor and information transmission functions except for the auditory function and some brain regions exhibited functional changes only in the one-sided impairment group. In addition, the severity of hearing impairment is related with the functional activities in the bilateral Heschl's gyrus, bilateral insula, right superior temporal gyrus, and left middle frontal gyrus.ConclusionIn conclusion, alterations in functional activity are observed in the brains of patients with long-term hearing impairments and multiple brain regions within different functional networks are involved in the brain functional remodeling. The brain reintegration mechanism appears to be asymmetrical and the lateralization pattern in the contralateral brain hemisphere for auditory information processing related with the severity of hearing impairment.
       
  • Tweaking the Intern Year Schedule
    • Abstract: Publication date: November 2019Source: Academic Radiology, Volume 26, Issue 11Author(s): Tushar Garg, Apurva Shrigiriwar
       
  • Differentiation Between Multiple System Atrophy and Other Spinocerebellar
           Degenerations Using Diffusion Kurtosis Imaging
    • Abstract: Publication date: November 2019Source: Academic Radiology, Volume 26, Issue 11Author(s): Kenji Ito, Chigumi Ohtsuka, Kunihiro Yoshioka, Tetsuya Maeda, Suguru Yokosawa, Futoshi Mori, Tsuyoshi Matsuda, Yasuo Terayama, Makoto SasakiRationale and ObjectiveDifferentiation between multiple system atrophy (MSA) and other spinocerebellar degenerations showing cerebellar ataxia is often difficult. Hence, we investigated whether magnetic resonance diffusion kurtosis imaging (DKI) could detect pathological changes that occur in these patients and be used for differential diagnosis.MethodsThirty-six subjects (12 patients with MSA accompanied by predominant cerebellar ataxia [MSA-C], 10 patients with spinocerebellar ataxias [SCAs] or sporadic adult-onset ataxia of unknown etiology [SAOA], and 14 healthy controls) were examined using 1.5- or 3-T magnetic resonance scanners. From the DKI data, the mean kurtosis, fractional anisotropy, and mean diffusivity values of the pontine crossing tract (PCT), middle cerebellar peduncle, and cerebellum were automatically measured, and the ratios against the values of the corpus callosum were calculated.ResultsWe found significant decreases in mean kurtosis and fractional anisotropy ratios in the PCT and middle cerebellar peduncle, and a significant increase in the mean diffusivity ratio in the PCT in the MSA-C group, as compared with the SCA/SAOA and control groups (p < 0.027–0.001). Among these metrics, there were no significant differences in the diagnostic performance. By contrast, the ratios in the cerebellum showed no significant differences between the MSA-C and SCA/SAOA groups but were significantly altered when compared with the controls (p < 0.001).ConclusionQuantitative DKI analyses can be used to differentiate between patients with MSA-C and those with SCA/SAOA.
       
  • Coronary CT Angiography in Challenging Patients: High Heart Rate and
           Atrial Fibrillation. A Review
    • Abstract: Publication date: November 2019Source: Academic Radiology, Volume 26, Issue 11Author(s): Saima Mushtaq, Edoardo Conte, Eleonora Melotti, Daniele AndreiniDespite several strategies have been developed by different vendors to improve image quality and diagnostic accuracy of coronary CT angiography performed at high heart rate (HR) and HR variability, as in patients with atrial fibrillation (AF), some concerns and small clinical experience characterize these subsets of challenging patients. However, patients with AF have been reported to have higher risk of cardiovascular events and noninvasive evaluation of suspected coronary artery disease in this setting may be of extreme clinical interest. The goal of this review is to provide to the reader an overview on the use of cardiac CT in patients with AF and high HR and to outline the technological improvements recently introduced in the clinical field that may enable to definitively overcome the limitations of cardiac CT in this challenging scenario.
       
  • Radiological Advances in Pancreatic Islet Transplantation
    • Abstract: Publication date: November 2019Source: Academic Radiology, Volume 26, Issue 11Author(s): Donal Cahill, Fernanda Zamboni, Maurice N. CollinsType 1 diabetes mellitus (T1DM) is characterized by hyperglycemia, owing to the loss of pancreatic β cells in response to an autoimmune reaction leading to a state of absolute insulin deficiency. T1DM treatment is shifting from exogenous insulin replacement therapy toward pancreatic β-cell replacement, to restore physiologically responsive insulin secretion to variations in blood glucose levels. β-cell replacement strategies include human whole pancreas transplantation, islet transplantation with cell encapsulation and bioengineered pancreas. Interventional radiology and imaging modalities including positron emission tomography, single-photon emission computed tomography, magnetic resonance imaging, ultrasonography, and molecular imaging are imperative to enable successful β-cell replacement. Herein, the role of radiological modalities in the treatment of T1DM and its prospective use for noninvasive post-transplantation graft monitoring is discussed.
       
  • Automatic Breast and Fibroglandular Tissue Segmentation in Breast MRI
           Using Deep Learning by a Fully-Convolutional Residual Neural Network U-Net
           
    • Abstract: Publication date: November 2019Source: Academic Radiology, Volume 26, Issue 11Author(s): Yang Zhang, Jeon-Hor Chen, Kai-Ting Chang, Vivian Youngjean Park, Min Jung Kim, Siwa Chan, Peter Chang, Daniel Chow, Alex Luk, Tiffany Kwong, Min-Ying SuRationale and ObjectivesBreast segmentation using the U-net architecture was implemented and tested in independent validation datasets to quantify fibroglandular tissue volume in breast MRI.Materials and MethodsTwo datasets were used. The training set was MRI of 286 patients with unilateral breast cancer. The segmentation was done on the contralateral normal breasts. The ground truth for the breast and fibroglandular tissue (FGT) was obtained by using a template-based segmentation method. The U-net deep learning algorithm was implemented to analyze the training set, and the final model was obtained using 10-fold cross-validation. The independent validation set was MRI of 28 normal volunteers acquired using four different MR scanners. Dice Similarity Coefficient (DSC), voxel-based accuracy, and Pearson's correlation were used to evaluate the performance.ResultsFor the 10-fold cross-validation in the initial training set of 286 patients, the DSC range was 0.83–0.98 (mean 0.95 ± 0.02) for breast and 0.73–0.97 (mean 0.91 ± 0.03) for FGT; and the accuracy range was 0.92–0.99 (mean 0.98 ± 0.01) for breast and 0.87–0.99 (mean 0.97 ± 0.01) for FGT. For the entire 224 testing breasts of the 28 normal volunteers in the validation datasets, the mean DSC was 0.86 ± 0.05 for breast, 0.83 ± 0.06 for FGT; and the mean accuracy was 0.94 ± 0.03 for breast and 0.93 ± 0.04 for FGT. The testing results for MRI acquired using four different scanners were comparable.ConclusionDeep learning based on the U-net algorithm can achieve accurate segmentation results for the breast and FGT on MRI. It may provide a reliable and efficient method to process large number of MR images for quantitative analysis of breast density.
       
  • Changes in the Utilization of the BI-RADS Category 3 Assessment in
           Recalled Patients Before and After the Implementation of Screening Digital
           Breast Tomosynthesis
    • Abstract: Publication date: November 2019Source: Academic Radiology, Volume 26, Issue 11Author(s): Tricia Stepanek, Niki Constantinou, Holly Marshall, Ramya Pham, Cheryl Thompson, Christina Dubchuk, Donna PlechaRationale and ObjectivesThe purpose of this study was to compare the utilization of the Breast Imaging Reporting and Data System (BI-RADS) category 3 assessment in patients recalled from screening before and after the implementation of digital breast tomosynthesis (DBT).Materials and MethodsThis was a retrospective review of 11,478 digital mammography (DM) screening exams and 9350 DM+DBT screening exams. Lesions assigned a BI-RADS category 3 at diagnostic exam were classified as architectural distortions, asymmetries, calcifications, masses, and “other” and followed for a minimum of 2 years.ResultsThe addition of DBT to screening DM resulted in a 30.4% relative reduction (10.3 women per 1000) in the utilization of BI-RADS category 3 compared to screening DM alone (3.4% for DM versus 2.4% for DM+DBT; p < 0.0001). There was a statistically significant change in the distribution of category 3 findings with DM+DBT characterized by an increase in calcifications and architectural distortions and a decrease in asymmetries. There was no change in category 3 assessment for masses. Although both cohorts had delayed cancer detection rates that exceeded the recommended 2% benchmark (2.3% for DM and 3.6% for DM+DBT), when limited to invasive malignancies, the delayed cancer detection rates were below the 2% benchmark (1.5% for DM and 0.9% for DM+DBT). Screening DM+DBT resulted in a 9.2% relative reduction in recall rate compared to DM (13.0% for DM versus 11.8% for DM+ DBT, p = 0.012).ConclusionImplementation of DBT in the screening population decreased the overall number of patients assigned to short-term follow-up by 10.3 per 1000 women while maintaining comparable rates of delayed cancer detection.
       
  • How to Reduce False Positive Recall Rates in Screening Mammography'
    • Abstract: Publication date: November 2019Source: Academic Radiology, Volume 26, Issue 11Author(s): Almir G.V. Bitencourt, Carolina Rossi Saccarelli, Elizabeth A. Morris
       
  • Machine Learning-based Analysis of Rectal Cancer MRI Radiomics for
           Prediction of Metachronous Liver Metastasis
    • Abstract: Publication date: November 2019Source: Academic Radiology, Volume 26, Issue 11Author(s): Meng Liang, Zhengting Cai, Hongmei Zhang, Chencui Huang, Yankai Meng, Li Zhao, Dengfeng Li, Xiaohong Ma, Xinming ZhaoRationale and ObjectivesTo use machine learning-based magnetic resonance imaging radiomics to predict metachronous liver metastases (MLM) in patients with rectal cancer.Materials and MethodsThis study retrospectively analyzed 108 patients with rectal cancer (54 in MLM group and 54 in nonmetastases group). Feature selection were performed in the radiomic feature sets extracted from images of T2-weighted image (T2WI) and venous phase (VP) sequence respectively, and the combining feature set with 2058 radiomic features incorporating two sequences with the least absolute shrinkage and selection operator method. Five-fold cross-validation and two machine learning algorithms (support vector machine [SVM]; logistic regression [LR]) were utilized for predictive model constructing. The diagnostic performance of the models was evaluated by receiver operating characteristic curves with indicators of accuracy, sensitivity, specificity and area under the curve, and compared by DeLong test.ResultsFive, 8, and 22 optimal features were selected from 1029 T2WI, 1029 VP, and 2058 combining features, respectively. Four-group models were constructed using the five T2WI features (ModelT2), the 8 VP features (ModelVP), the combined 13 optimal features (Modelcombined), and the 22 optimal features selected from 2058 features (Modeloptimal). In ModelVP, the LR was superior to the SVM algorithm (P = 0.0303). The Modeloptimal using LR algorithm showed the best prediction performance (P = 0.0019–0.0081) with accuracy, sensitivity, specificity, and area under the curve of 0.80, 0.83, 0.76, and 0.87, respectively.ConclusionRadiomics models based on baseline rectal magnetic resonance imaging has high potential for MLM prediction, especially the Modeloptimal using LR algorithm. Moreover, except for ModelVP, the LR was not superior to the SVM algorithm for model construction.
       
  • Renal Adiposity Does not Preclude Quantitative Assessment of Renal
           Function Using Dual-Energy Multidetector CT in Mildly Obese Human Subjects
           
    • Abstract: Publication date: November 2019Source: Academic Radiology, Volume 26, Issue 11Author(s): Christopher M. Ferguson, Alfonso Eirin, Gregory J. Michalak, Ahmad F. Hedayat, Abdelrhman M. Abumoawad, Ahmed Saad, Xiangyang Zhu, Stephen C. Textor, Cynthia H. McCollough, Lilach O. LermanRationale and ObjectivesMultidetector computed tomography (MDCT) is useful for measuring in the research setting single-kidney perfusion and function using iodinated contrast time-attenuation curves. Obesity promotes deposition of intrarenal fat, which might decrease tissue attenuation and thereby interfere with quantification of renal function using MDCT. The purpose of this study was to test the hypothesis that background subtraction adequately accounts for intrarenal fat deposition in mildly obese human subjects during renal contrast enhanced dynamic CT.Materials and MethodsWe prospectively recruited seventeen human subjects stratified as lean or mildly obese based on body mass index below or over 30 kg/m2, respectively. Renal perfusion was quantified from CT-derived indicator-dilution curves after background subtraction. Dual-energy MDCT images were postprocessed to generate iodine and virtual-noncontrast datasets, and the ratios between kidney/aorta CT numbers and iodine values calculated as surrogates of renal function.ResultsSubcutaneous adipose tissue was increased in obese subjects. Virtual-noncontrast maps revealed in obese patients a decrease in basal cortical and medullary attenuation. Overall, basal attenuation inversely correlated with body mass index, in line with renal fat deposition. Contrarily, the kidney/aorta CT attenuation (after background subtraction) and kidney/aorta iodine ratios were similar between lean and obese subjects and correlated directly. These observations show that following background subtraction, the CT number reliably reflects basal tissue attenuation.ConclusionTherefore, our findings support our hypothesis that background subtraction enables reliable assessment of kidney function in mildly obese subjects using MDCT, despite decreased basal attenuation due to renal adiposity.
       
  • Application of Adaptive Statistical Iterative Reconstruction-V With
           Combination of 80 kV for Reducing Radiation Dose and Improving Image
           Quality in Renal Computed Tomography Angiography for Slim Patients
    • Abstract: Publication date: November 2019Source: Academic Radiology, Volume 26, Issue 11Author(s): Zhanli Ren, Xirong Zhang, Zhijun Hu, Dou Li, Zhentang Liu, Donghong Wei, Yongjun Jia, Nan Yu, Yong Yu, Yuxin Lei, Xiaoxia Chen, Changyi Guo, Zhanliang Ren, Taiping HeObjectivesTo explore the application of adaptive statistical iterative reconstruction-V (ASIR-V) with combination of 80 kV for reducing radiation dose and improving image quality in renal computed tomography angiography (CTA) for slim patients compared with traditional filtered back projection (FBP) reconstruction using 120 kV.MethodsEighty patients for renal CTA were prospectively enrolled and randomly divided into group A and group B. Group A used 120 kV and 600 mgI/kg contrast agent and FBP reconstruction, while group B used 80 kV and 350 mgI/kg contrast agent and both FBP and ASIR-V reconstruction from 10%ASIR-V to 100%ASIR-V with 10%ASIR-V interval. The CT values and SD values of the right renal artery and left renal artery were measured to calculate the signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR). The image quality was subjectively scored by two experienced radiologists blindly using a five-point criterion. The contrast agent, volumetric CT dose index (CTDIvol), and dose length product in both groups were recorded and the effective radiation dose was calculated.ResultsThere were no significant difference in patient characteristics between two groups (p> 0.05). The CTDIvol, dose length product and effective radiation dose in group B were 59.0%, 65.0%, and 65.1% lower than those in group A, respectively (all p < 0.05), and the contrast agent in group B was 42.2% lower than that in group A (p < 0.05). In group B, with the increase of ASIR-V percentage, CT values showed no significant difference, SD values decreased gradually, SNR values and CNR values increased gradually. The CT values showed no statistically significant difference (p> 0.05) between two groups with different reconstructions. The SD values with 40%ASIR-V to 100%ASIR-V reconstruction in group B was significantly lower(p < 0.5), while the SNR values with 50% ASIR-V to 100% ASIR-V reconstruction and CNR values with 70%ASIR-V to 100%ASIR-V were significantly higher than those of group A with FBP reconstruction (p < 0.5). Two radiologists had excellent consistency in subjective scores of image quality for renal CTA (kappa>0.75, p < 0.05). The subjective scores with 60% ASIR-V to 90% ASIR-V in group B were significantly higher than those of FBP in group A (p < 0.5), of which 70%ASIR-V reconstruction obtained the highest subjective score for renal CTA.ConclusionASIR-V with combination of 80 kV can significantly reduce effective radiation dose (about 65.1%) and contrast agent (about 42.2%) and improve image quality in renal CTA for slim patients compared with traditional FBP reconstruction using 120 kV, and the 70% ASIR-V was the best reconstruction algorithm in 80 kV renal CTA.Advances in KnowledgeUsing 80 kV with combination of ASIR-V can significantly reduce radiation dose and contrast agent dose as well as improve image quality in renal CTA for thin patients when compared with FBP using 120 kV.
       
  • Image-Guided Percutaneous Gastrostomy Tube Placement is Safe in Patients
           Requiring Aspirin 325 mg
    • Abstract: Publication date: November 2019Source: Academic Radiology, Volume 26, Issue 11Author(s): Ryan S. Dolan, Daryl Goldman, Mark El-Deiry, Nima Kokabi, Zachary L. Bercu, Janice Newsome, Jonathan G. MartinRationale and ObjectivesRequests for gastrostomy tube placement in patients on aspirin (ASA) 325 mg are common, particularly in patients following reconstructive surgery for head and neck cancer, but periprocedural guidelines and recommendations regarding management of high dose aspirin are inconsistent. The purpose of this study was to assess the bleeding risk of percutaneous gastrostomy tube placement in patients on ASA 325 mg.Materials and MethodsThis retrospective study of 213 patients who underwent image-guided “push” percutaneous gastrostomy tube placement compared rates of significant bleeding and other secondary outcomes (including all-cause mortality within 30 days, procedure-related mortality, bowel perforation, abdominal abscess, peritonitis, aspiration pneumonia, intraprocedural airway complications, and tube dislodgement) between patients maintained on ASA 325 mg and patients not on antiplatelet or anticoagulation therapy.ResultsNo significant bleeding episodes occurred in patients on ASA 325 mg, compared to three episodes in patients not on ASA 325 mg (p = 0.37). A patient in each group had aspiration pneumonia possibly related to tube placement. There were no other notable secondary outcomes, including intraprocedural airway complications in this population with complex head and neck anatomy.ConclusionThese findings suggest that holding ASA 325 mg in patients undergoing percutaneous gastrostomy tube placement is not necessary, especially in patients in whom holding ASA would pose considerable risk. Further multi-institutional longitudinal study is warranted to validate these results.
       
  • Prognostic Value of the Pretreatment Primary Lesion Quantitative Dynamic
           
    • Abstract: Publication date: November 2019Source: Academic Radiology, Volume 26, Issue 11Author(s): Yuhui Qin, Xiaoping Yu, Jing Hou, Ying Hu, Feiping Li, Lu Wen, Qiang Lu, Siye LiuRationale and ObjectivesEarly identifying the long-term outcome of chemoradiotherapy is helpful for personalized treatment in nasopharyngeal carcinoma (NPC). This study aimed to investigate the prognostic significance of pretreatment quantitative dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) for NPC.Materials and MethodsThe relationships between the prognosis and pretreatment quantitative DCE-MRI (Ktrans, Kep, Ve, and fpv) values of the primary tumors were analyzed in 134 NPC patients who received chemoradiotherapy. Kaplan-Meier analysis was performed to calculate the local-regional relapse-free survival (LRRFS), local relapse-free survival (LRFS), regional relapse-free survival, distant metastasis-free survival (DMFS), progression-free survival, and overall survival rates. Cox proportional hazards model was used to explore the independent predictors for prognosis.ResultsThe local-failure group had significantly higher Ve (p = 0.033) and fpv values (p = 0.005) than the non-local-failure group. The Ve-high group showed significantly lower LRRFS (p = 0.015) , LRFS (p = 0.013) , DMFS (p = 0.027) and progression-free survival (p = 0.035) rates than the Ve-low group. The fpv-high group exhibited significantly lower LRRFS (p = 0.004) and LRFS (p = 0.005) rates than the fpv-low group. Ve was the independent predictor for LRRFS (p = 0.008), LRFS (p = 0.007), DMFS (p = 0.041), and overall survival (p = 0.022). fpv was the independent indicator for LRRFS (p = 0.003) and LRFS (p = 0.001).ConclusionBaseline quantitative DCE-MRI may be valuable in predicting the prognosis for NPC.
       
  • Discrimination Between Solitary Brain Metastasis and Glioblastoma
           Multiforme by Using ADC-Based Texture Analysis: A Comparison of Two
           Different ROI Placements
    • Abstract: Publication date: November 2019Source: Academic Radiology, Volume 26, Issue 11Author(s): Guoqin Zhang, Xin Chen, Sijing Zhang, Xiuhang Ruan, Cuihua Gao, Zaiyi Liu, Xinhua WeiRationale and ObjectivesTo explore the value of texture analysis based on the apparent diffusion coefficient (ADC) value and the effect of region of interest (ROI) placements in distinguishing glioblastoma multiforme (GBM) from solitary brain metastasis (sMET).Materials and MethodsSixty-two patients with pathologically confirmed GBM (n = 36) and sMET (n = 26) were retrospectively included. All patients underwent diffusion-weighted imaging with b values of 0 and 1000 s/mm2, and the ADC maps were generated automatically. ROIs were placed on the largest whole single-slice tumor (ROI1) and the enhanced solid portion (ROI2) of the ADC maps, respectively. The texture feature metrics of the histogram and gray-level co-occurrence matrix were then extracted by using in-house software. The parameters of the texture analysis were compared between GBM and sMET, using the Mann–Whitney U test. A receiver operating characteristic (ROC) curve analysis was performed to determine the best parameters for distinguishing between GBM from sMET.ResultsHomogeneity and the inverse difference moment (IDM) of GBM were significantly higher than those of sMET in both ROIs (ROI1, p = 0.014 for homogeneity and p = 0.048 for IDM; ROI2, p 0.05).ConclusionThe ADC-based texture analysis can help differentiate GBM from sMET, and the ROI on the solid portion would be recommended to calculate the ADC-based texture metrics.
       
  • Advanced Virtual Monoenergetic Imaging: Improvement of Visualization and
           Differentiation of Intramuscular Lesions in Portal-Venous-phase
           Contrast-enhanced Dual-energy CT
    • Abstract: Publication date: November 2019Source: Academic Radiology, Volume 26, Issue 11Author(s): Mareen S. Kraus, Nadja Selo, Lena S. Kiefer, Michael Esser, Omar M. Albtoush, Jakob Weiss, Julian L. Wichmann, Fabian Bamberg, Ahmed E. OthmanPurposeTo evaluate the effect of advanced monoenergetic imaging (MEI+) postprocessing algorithm on the visualization of various intramuscular lesions on portal-venous-phase contrast-enhanced dual-energy computed tomography (DECT).Material and MethodsThirty-nine patients (64.3 ± 11.1 years; 26 males) with various intramuscular lesions ranging from malignancy, bleeding, inflammation, edematous changes, and benign neoplasms were included and underwent DECT (100/Sn150kV). Postprocessing with MEI+ technique was used to reconstruct images at four different keV levels (40, 60, 80, 100) and compared to the standard portal-venous-phase CT (CTpv) images. Image quality was assessed qualitatively (conspicuity, delineation, sharpness, noise, and confidence) by two independent readers using 5-point Likert scales, 5 = excellent; as well as quantitatively by calculating signal-to-noise ratios (SNR), contrast-to-noise ratios (CNR), and area under the receiver operating characteristic (ROC) curve (AUC) for lesion characterization.ResultsHighest lesion enhancement and diagnostic confidence were observed in MEI+ 40 keV, with significant differences to CTpv (p < 0.001), as well as for malignant lesions (highest conspicuity, noise, and sharpness in MEI+ 40 keV; p < 0.001). CNR calculations revealed highest values for MEI+ 40 keV followed by 60 keV with significant differences to CTpv, and increasing energy levels. ROC analysis showed highest diagnostic accuracy for 40-keV MEI+ datasets regarding the detection of malignant/benign lesions with AUC values of 98.9% (95%-confidence interval: 96.5, 100) and a standard error of 1.2, further AUC values decreased to 83.6% for MEI+100.ConclusionMEI+ at low keV levels can significantly improve lesion detection of benign versus malignant intramuscular entities in patients undergoing portal-venous-phase DECT scans due to increased CNR.
       
  • Confronting the US's Highly Uneven State-by-State Distribution of
           Diagnostic Radiology Residency Positions
    • Abstract: Publication date: November 2019Source: Academic Radiology, Volume 26, Issue 11Author(s): Mohsin Mukhtar, Korbin Davis, Aaron P. Kamer, Richard B. Gunderman
       
  • Comparison of Whole Heart Computed Tomography Scanners for Image Quality
           Lower Radiation Dosing in Coronary Computed Tomography Angiography: The
           CONVERGE Registry
    • Abstract: Publication date: November 2019Source: Academic Radiology, Volume 26, Issue 11Author(s): Nirali Patel, Dong Li, Rine Nakanishi, Badiha Fatima, Daniele Andreini, Gianluca Pontone, Edoardo Conte, Rachael O'Rourke, Eranthi Jayawardena, Christian Hamilton-Craig, Manojna Nimmagadda, Matthew J. BudoffRationale and ObjectivesNovel technology in coronary computed tomographic angiography allows assessment of coronary artery disease with high image quality (IQ). There are currently two wide detector “whole heart” coverage scanners available, which avoid misregistration artifacts. However, there are no data directly comparing IQ between the two scanners. The aim of the current study is to investigate if IQ is different between the most scanners of GE and Toshiba broad detector scanners.Materials and MethodsProspective, observational, multicenter international cohort study comparing 236 consecutive patients who underwent coronary computed tomographic angiography using whole-heart scanners; 126 patients on scanner S1 ( Aquilion ONE Vision, Toshiba), and 110 patients on scanner S2 (Revolution CT, GE Healthcare). Hounsfield units were measured using regions of interest in the descending aorta at 6 points (cranial slice, level of the visualized first, second, third, and fourth spines, and the caudal slice). We also compared the coverage length (z-axis) of the full width field of view between a single rotation of the two scanners.ResultsEvaluating mean CT attenuation values Hounsfield units through the scan range, are progressively reduced across the descending aorta in the S1 group, resulting in the larger difference of contrast brightness between the cranial and caudal slices compared to the S2 group (absolute difference: S2 13.0 ± 4.4 vs S1 141.9 ± 16.4, p < 0.0001; Percent difference: 19.3 ± 2.1 vs −3.4 ± 1.2,
       
  • CT Boost, an Important Step in Endoleak Diagnosis
    • Abstract: Publication date: November 2019Source: Academic Radiology, Volume 26, Issue 11Author(s): Erica B. Stein, David M. Williams
       
  • Contrast Enhancement Boost Technique at Aortic Computed Tomography
           Angiography: Added Value for the Evaluation of Type II Endoleaks After
           Endovascular Aortic Aneurysm Repair
    • Abstract: Publication date: November 2019Source: Academic Radiology, Volume 26, Issue 11Author(s): Hitoshi Iizuka, Yasuhiro Yokota, Masafumi Kidoh, Seitaro Oda, Osamu Ikeda, Yoshitaka Tamura, Yoshinori Funama, Daisuke Sakabe, Takeshi Nakaura, Yasuyuki Yamashita, Daisuke UtsunomiyaRationale and ObjectivesDelayed-phase acquisition of the computed tomography (CT) angiography is important for the evaluation of type II endoleaks after endovascular aortic aneurysm repair because the endoleak cavity area is associated with aneurysm sac expansion. Contrast enhancement boost (CE-boost) is a postprocessing technique for increasing the degree of contrast enhancement on contrast-enhanced CT. We aimed to investigate the usefulness of the CE-boost technique for the visualization of type II endoleaks.Materials and MethodsThis retrospective study included 28 patients with type II endoleaks after endovascular aortic aneurysm repair who underwent triphasic contrast-enhanced CT. Objective (CT number, signal-to-noise ratio, and contrast-to-noise ratio) and subjective quality analyses using a four-point scale (1, poor; 4, excellent) were performed for the conventional early- and delayed-phase images as well as CE-boost delayed-phase images.ResultsThe CE-boost delayed-phase images yielded a significantly higher CT number (134.5 ± 41.7 HU), signal-to-noise ratio (23.4 ± 10.5), and contrast-to-noise ratio (15.3 ± 8.4) and showed a significantly larger endoleak area (145.0 ± 134.8 mm2) than did the conventional early-phase (95.6 ± 53.2 HU, 7.3 ± 4.7, 4.0 ± 4.2, and 56.2 ± 99.3 mm2, respectively) and delayed-phase (110.5 ± 33.3 HU, 8.2 ± 2.7, 4.9 ± 2.0, and 124.8 ± 131.9 mm2, respectively) images (p < 0.01). The endoleak visibility score was highest for the CE-boost delayed-phase images (2.0 ± 1.0, 3.0 ± 0.6, and 3.4 ± 0.7 for conventional early-phase, delayed-phase, and delayed-phase CE-boost images, respectively; p < 0.001).ConclusionThe CE-boost technique facilitates clear visualization of type II endoleak cavities.
       
  • “Code-Stroke” CT Perfusion; Challenges and Pitfalls
    • Abstract: Publication date: November 2019Source: Academic Radiology, Volume 26, Issue 11Author(s): Houman Sotoudeh, Asim K. Bag, Michael David BrooksRationale and ObjectivesRegarding the most recent ischemic stroke treatment guideline, perfusion imaging has been recommended up to 24 hours after initial symptoms of brain infarction. Patients with a significant amount of salvageable peri-infarct ischemia and no contraindications benefit from delayed thrombolysis and intra-arterial thrombectomy. This approach causes increasingly more CT perfusion to be done in the subacute phase of ischemic stroke. CT perfusion findings in this “subacute phase” are slightly different from “hyper-acute” ischemic stroke. The interpreting radiologist must be confident in reporting the CT perfusion study in an urgent setting since these studies are under the umbrella of “code-stroke” and should be read in minutes. In addition, results of the CT perfusion have a critical effect on the patient's outcome and misinterpretation can be fatal in that underestimation of the salvageable ischemia excludes the patient from potential effective treatment. Underestimation of infarct volume may cause unnecessary thrombolysis/thrombectomy and potentially fatal intracranial hemorrhage.Materials and MethodsIn this review, we are trying to explain the basic concept of “code-stroke” CT perfusion, typical findings, and pitfalls in a practical way.
       
  • The Importance of Imaging Informatics and Informaticists in the
           Implementation of AI
    • Abstract: Publication date: Available online 19 October 2019Source: Academic RadiologyAuthor(s): Tessa S. CookImaging informatics is critical to the success of AI implementation in radiology. An imaging informaticist is a unique individual who sits at the intersection of clinical radiology, data science, and information technology. With the ability to understand each of the different domains and translate between the experts in these domains, imaging informaticists are now essential players in the development, evaluation, and deployment of AI in the clinical environment.
       
  • Artificial Intelligence in Medicine: Where Are We Now'
    • Abstract: Publication date: Available online 19 October 2019Source: Academic RadiologyAuthor(s): Sagar Kulkarni, Nuran Seneviratne, Mirza Shaheer Baig, Ameer Hamid Ahmed KhanArtificial intelligence in medicine has made dramatic progress in recent years. However, much of this progress is seemingly scattered, lacking a cohesive structure for the discerning observer. In this article, we will provide an up-to-date review of artificial intelligence in medicine, with a specific focus on its application to radiology, pathology, ophthalmology, and dermatology. We will discuss a range of selected papers that illustrate the potential uses of artificial intelligence in a technologically advanced future.
       
  • The Diagnostic Value of MRI for Preoperative Staging in Patients with
           Endometrial Cancer: A Meta-Analysis
    • Abstract: Publication date: Available online 18 October 2019Source: Academic RadiologyAuthor(s): Qiu Bi, Yuhui Chen, Kunhua Wu, Junna Wang, Ying Zhao, Bo Wang, Ji DuObjectivesTo assess the diagnostic accuracy of magnetic resonance imaging (MRI) for detecting myometrial invasion, cervical invasion, and lymph node metastases in endometrial cancer.Materials and MethodsA systematic literature search was performed in PubMed, Embase, Cochrane Library, Web of Science, and Clinical trials. The methodological quality of each study was assessed by using the standard Quality Assessment of Diagnostic Accuracy Studies-2. Statistical analysis included evaluating publication bias, assessing threshold effect, exploring heterogeneity, pooling data, meta-regression, forest plot, and summary receiver-operating characteristics curves construction.ResultsFourteen studies could be analyzed. For detecting deep myometrial invasion, the pooled sensitivity and specificity were 0.79 and 0.81 respectively, and patients younger than 60 years old demonstrated higher sensitivity (0.84) and specificity (0.90). The diagnostic accuracy is highest by jointly using T2-weighted image, dynamic contrast-enhanced MRI, and diffusion weighted imaging to detect the deep myometrial invasion. There were low sensitivity and high specificity for the diagnosis of cervical invasion (0.53, 0.95), cervical stromal invasion (0.50, 0.95), pelvic or/and para-aortic lymph node metastases (0.59, 0.95), and pelvic lymph node metastases (0.65, 0.95).ConclusionMRI has good diagnostic performance for assessing myometrial invasion in patients with endometrial cancer, especially in patients younger than 60 years old. Dynamic contrast-enhanced MRI and diffusion weighted imaging can help improve sensitivity and specificity for detecting myometrial invasion. MRI shows high specificity for detecting cervical invasion and lymph node metastases in endometrial cancer.
       
  • Burnout Phenomenon and Its Predictors in Radiology Residents
    • Abstract: Publication date: Available online 16 October 2019Source: Academic RadiologyAuthor(s): Abdulmajeed Bin Dahmash, Fawziah Khalid Alorfi, Abdulaziz Alharbi, Abdulrahman Aldayel, Ahmed M. Kamel, Mohammed AlmoaiqelRationale and ObjectivesThe purpose of this study is to evaluate the prevalence of burnout and its associated risk factors in radiology residents in Saudi Arabia.Materials and MethodsThis cross-sectional study was conducted in February 2019, and all radiology residents in Riyadh, Saudi Arabia, were invited to complete a survey that contained a validated measure of burnout (Maslach Burnout Inventory-Human Services Survey) alongside possible predictors of burnout.ResultsA total of 108 responses were received, for a response rate of 49.7%. High overall burnout was reported by 24.1% of respondents, high emotional exhaustion (EE) by 56.5%, high depersonalization by 31.5%, and low sense of personal accomplishment (PA) by 64.8%. The significant predictors of burnout included satisfaction with work/life balance (OR = 0.35, 95% CI = 0.03 to 0.43, p = 0.002) and exercising (OR = 0.31, 95% CI = 0.1 to 1, p = 0.07). Married residents were more prone to have a low sense of PA in addition to dissatisfied residents with hospital staff appreciation (OR = 4.8, 95% CI = 1.48 to 15.5, p = 0.01) and (OR = 0.59, 95% CI = 0.37 to 0.94, p = 0.03), respectively.ConclusionOne-fourth of the radiology residents studied showed high rates of burnout, and more than half the residents reported high rates of EE. The residents scored very poorly in the sense of PA. The radiology residents who were satisfied with their work/life balance had lower burnout rates, in addition to lower EE and a higher sense of PA.
       
  • Safety and Efficacy Studies of Vertebroplasty with Dual Injections for the
           Treatment of Osteoporotic Vertebral Compression Fractures: Preliminary
           Report
    • Abstract: Publication date: Available online 16 October 2019Source: Academic RadiologyAuthor(s): Pijian Cao, Weimin Hao, Lu Zhang, Qinglin Zhang, Xunwei Liu, Min LiPurposeTo evaluate the clinical safety and efficacies of percutaneous vertebroplasty (PVP), percutaneous vertebroplasty with dual injections (PVPDI), and percutaneous kyphoplasty (PKP) for the treatment of osteoporotic vertebral compression fractures (OVCFs), a retrospective study of 90 patients with OVCFs who had been treated by PVP (n = 30), PVPDI (n = 30), and PKP (n = 30) was conducted in this work.MethodsThe clinical efficacies of these three treatments were evaluated by comparing their PMMA cement leakages, cement patterns, height restoration percentages, wedge angles, visual analogue scales, and Oswestry disability index (ODI) at the pre- and postoperative time points.ResultsTen percent, 6.7%, and 0% of patients had PMMA leakage in PVP, PVPDI, and PKP groups, respectively. Three (solid, trabecular, and mixed patterns), two (trabecular and mixed patterns), and two (solid and mixed patterns) types of cement patterns were observed in PVP, PVPDI, and PKP groups, respectively. PVP and PVPDI treatments had similar and less height restoration ability than PKP treatment. All the PVP, PVPDI, and PKP treatments had significant and similar ability in pain relief and functional recovery ability for the treatment of OVCFs. Microfractures after the surgery occurred after PVP and PKP treatments.ConclusionThese results indicate minimally invasive techniques were effective methods for the treatment of OVCFs. Moreover, these initial outcomes suggest PVPDI treatment has great value and is worth promoting vigorously in orthopedics clinics.
       
  • The Value of Contrast-Enhanced CT in the Detection of Residual Disease
           After Neo-Adjuvant Chemotherapy in Ovarian Cancer
    • Abstract: Publication date: Available online 16 October 2019Source: Academic RadiologyAuthor(s): He An, Keith W.H. Chiu, K.Y. Tse, Hextan Y.S. Ngan, Pek-Lan Khong, Elaine Y.P. LeeRationale and ObjectivesTo evaluate the diagnostic performance of contrast-enhanced computed tomography (CT) in predicting residual disease following neo-adjuvant chemotherapy (NACT) in stage III/IV ovarian cancer.Materials and MethodsThis was a retrospective observational cohort study including consecutive patients with primary stage III/IV ovarian cancer who received NACT before interval debulking surgery. CT findings before interval debulking surgerywere correlated with histological/surgical findings. Diagnostic characteristics were calculated on patient-based and lesion-based analyses. False negative results on peritoneal carcinomatosis detection were correlated with lesion size and site.ResultsOn patient-based analysis, CT (n = 58) had a sensitivity, specificity, positive predictive value, negative predictive value and accuracy of 92.16%, 57.14%, 94.00%, 50.00%, and 87.93%. On lesion-based analysis, the sensitivity, specificity, positive predictive value, negative predictive value, and accuracy were 63.01%, 73.47%, 82.51%, 50.00%, and 66.51%. False negative results were associated with lesion size (p < 0.001). The diagnostic performance of CT on the detection of peritoneal carcinomatosis was low at the subdiaphragmatic spaces, bowel serosa and mesentery (p < 0.001).ConclusionCT had low negative predictive value in determining residual disease following NACT on both patient-based and lesion-based analyses, especially for non-measurable lesions and at the subdiaphragmatic spaces, bowel serosa and mesentery.
       
  • Initial Clinical Experience of Virtual Monoenergetic Imaging Improves
           Stent Visualization in Lower Extremity Run-Off CT Angiography by
           Dual-Layer Spectral Detector CT
    • Abstract: Publication date: Available online 15 October 2019Source: Academic RadiologyAuthor(s): Daming Zhang, Yanting Xie, Yining Wang, Ning Guo, Yun Wang, Zhengyu Jin, Huadan XueRationale and ObjectivesVirtual monoenergetic imaging (VMI) may improve stent visualization in lower extremity run-off computed tomography angiography. The purpose of this study was to evaluate the image quality (IQ) of stents and to determine the optimal kiloelectron volt (keV) level of VMI images for stent evaluation compared to conventional CT images.Materials and MethodsThis study included 32 patients with prior stent placement who underwent run-off computed tomography angiography on a dual-layer spectral detector CT scanner. Thirteen image series were evaluated for each stent, including conventional CT and 12 VMI datasets from 40 keV to 150 keV obtained in 10-keV intervals. Attenuation, SD, contrast-to-noise ratio, and signal-to-noise ratio of the native vessel and the vessel with a stent were evaluated. The diameter of the stent was measured in all 13 image series. The IQ was evaluated by two readers using a five-point scale (1 = poor IQ, 5 = excellent IQ).ResultsA total of 39 stents in 29 patients were evaluated. Compared to conventional CT, attenuation of the native vessel and the vessel with a stent was higher at 40–60 keV, and the SD was equal or lower at 50–150 keV. Based on the attenuation and SD of VMI images, the contrast-to-noise ratio and signal-to-noise ratio were higher at 40–70 keV, among which the highest ratios were obtained at 40 keV. The stent diameter was equal or larger at 60–150 keV, and the lowest stent diameter underestimation occurred at 100 keV. The IQ was equal or higher, ranging from 60 to 100 keV in comparison with conventional CT, and the highest IQ score occurred at 90 keV.ConclusionThis quantitative and qualitative assessment of VMI images and conventional images indicated that IQ improvement and more accurate stent lumen evaluation on lower extremity run-off CT angiography can be achieved by dual-layer spectral detector CT.
       
  • Unboxing AI - Radiological Insights Into a Deep Neural Network for Lung
           Nodule Characterization
    • Abstract: Publication date: Available online 14 October 2019Source: Academic RadiologyAuthor(s): Vasantha Kumar Venugopal, Kiran Vaidhya, Murali Murugavel, Abhijith Chunduru, Vidur Mahajan, Suthirth Vaidya, Digvijay Mahra, Akshay Rangasai, Harsh MahajanRationale and ObjectivesTo explain predictions of a deep residual convolutional network for characterization of lung nodule by analyzing heat maps.Materials and MethodsA 20-layer deep residual CNN was trained on 1245 Chest CTs from National Lung Screening Trial (NLST) trial to predict the malignancy risk of a nodule. We used occlusion to systematically block regions of a nodule and map drops in malignancy risk score to generate clinical attribution heatmaps on 103 nodules from Lung Image Database Consortium image collection and Image Database Resource Initiative (LIDC-IDRI) dataset, which were analyzed by a thoracic radiologist. The features were described as heat inside nodule -bright areas inside nodule, peripheral heat continuous/interrupted bright areas along nodule contours, heat in adjacent plane -brightness in scan planes juxtaposed with the nodule, satellite heat - a smaller bright spot in proximity to nodule in the same scan plane, heat map larger than nodule bright areas corresponding to the shape of the nodule seen outside the nodule margins and heat in calcification.ResultsThese six features were assigned binary values. This feature vector was fedinto a standard J48 decision tree with 10-fold cross-validation, which gave an 85 % weighted classification accuracy with a 77.8% True Positive (TP) rate, 8% False Positive (FP) rate for benign cases and 91.8% TP and 22.2% FP rates for malignant cases. Heat Inside nodule was more frequently observed in nodules classified as malignant whereas peripheral heat, heat in adjacent plane, and satellite heat were more commonly seen in nodules classified as benign.ConclusionWe discuss the potential ability of a radiologist to visually parse the deep learning algorithm generated “heat map” to identify features aiding classification.
       
  • 11C-Methionine Integrated PET/MRI-Based Texture Analysis Features May Have
           a Potential Ability to Distinguish Oligodendroglioma (IDH-Mutant and
           1p/19q-Codeleted) From Varied Gliomas
    • Abstract: Publication date: Available online 11 October 2019Source: Academic RadiologyAuthor(s): Kai Zhao, Peng Yu, Zhe Xue, Jiajin Liu, Anhui Yao, Yue Zhao, Fuxing Yang, Jiahe Tian, Bainan XuRationale and ObjectivesDifferent histology and gene status of gliomas results in different natural history, treatment, and prognosis in different subgroups. Low-grade gliomas (LGGs) with isocitrate dehydrogenase (IDH) mutant and 1p/19q-codeleted are kind of gliomas with the most favorable outcome, reflecting operational strategy. Less invasive method for prediction of pathological type—even gene status—is desired.Materials and MethodsThis study investigates the potential ability of methionine-positron emission tomography (MET-PET) to determine LGGs with IDH-mutant and 1p/19q-codeleted through a retrospective review of information of 70 glioma patients. Patients underwent preoperative MET-PET, followed by operation and histopathological analysis including Immunohistochemistry and polymerase chain reaction analysis for IDH-mutant and fluorescence capillary electrophoresis analysis for 1p/19q codeletion. Texture analysis was performed for further data mining. The t-test and receiver operating characteristic curve analysis were conducted for statistical analysis.ResultsIn the whole cohort analysis, SUVmax, SUVmean and texture features (SD and median) of oligodendroglioma, IDH-mutant and 1p/19q-codeleted patients were lower than these values of other patients. In WHO grade II subgroup analysis, no statistical difference of conventional features was observed between groups. Texture analysis displayed higher diffEntropy, diffVariance, and entropy in oligodendroglioma, IDH-mutant and 1p/19q-codeleted patients. Receiver operating characteristic analysis suggested AUCs of some conventional features and texture features ranged from 0.722 to 0.892 that are effective for diagnosis, determining LGGs with IDH-mutant and 1p/19q-codeleted in this cohort and WHO II grade glioma subgroup analysis respectively.Conclusion11C-Methionine integrated PET/MRI based texture analysis and conventional features may be a promising noninvasive predictor for differentiating the varied gliomas.
       
  • Adaptive Tutorials Versus Web-Based Resources in Radiology: A Mixed
           Methods Analysis of Efficacy and Engagement in Senior Medical Students
    • Abstract: Publication date: October 2019Source: Academic Radiology, Volume 26, Issue 10Author(s): Stuart W.T. Wade, Michelle Moscova, Nicodemus Tedla, Daniel A. Moses, Noel Young, Merribel Kyaw, Gary M. VelanRationale and ObjectivesRadiology education is suited to delivery via e-learning which may be used to fill gaps in knowledge and help prepare medical students for internship. There is limited evidence of effectiveness of adaptive tutorials, a form of e-learning in a senior medical student cohort.Materials and MethodsA randomized mixed methods crossover trial was performed to assess effectiveness of adaptive tutorials on engagement and understanding of appropriate use and interpretation of basic imaging studies. Eighty-one volunteer medical students from years 5 and 6 of a 6-year program were randomly allocated to one of two groups. In the first phase of the trial on head CT, one group received access to adaptive tutorials and the other to peer-reviewed web-based resources. A cross over was performed and the second phase of the trial addressing chest CT commenced. Examination style assessments were completed at the end of each phase. At the trial's conclusion, an online questionnaire was provided to evaluate student perceptions of engagement and efficacy of each educational resource.ResultsAdaptive tutorial groups in both phases achieved higher mean scores than controls which were statistically significant in the first phase only. Students reported higher engagement and overall perceived value of the adaptive tutorials than controls.ConclusionAdaptive tutorials are overwhelmingly supported by senior medical students. Questionnaire responses suggest the engaging nature of the tutorials efficiently aids participation and knowledge retention which is in principle supported by test results.
       
  • Impact of Effective Detector Pixel and CT Voxel Size on Accurate
           Estimation of Blood Volume in Opacified Microvasculature
    • Abstract: Publication date: October 2019Source: Academic Radiology, Volume 26, Issue 10Author(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.
       
  • To Score or Not to Score—The USMLE Debate Continues
    • Abstract: Publication date: October 2019Source: Academic Radiology, Volume 26, Issue 10Author(s): Priscilla J. Slanetz
       
  • The USMLE Step 1 Pass/Fail Reporting Proposal: Another View
    • Abstract: Publication date: October 2019Source: Academic Radiology, Volume 26, Issue 10Author(s): J. Bryan Carmody, David Sarkany, Darel E. HeitkampThe Association of Program Directors in Radiology recently issued a statement endorsing continued reporting of results of the United States Medical Licensing Examination (USMLE) as a three-digit score. While this position was approved by the Association of Program Directors in Radiology Board of Directors, it does not reflect the opinions of all radiology program directors. Here, we present an argument in support of reporting USMLE results as pass/fail.As a psychometric instrument, the USMLE Step 1 is designed to assess basic science knowledge and intended to inform a binary decision on licensure. Due to a steadily-increasing burden of applications to review, program directors have increasingly relied upon scores for candidate screening. Such use has multiple adverse consequences. Student focus on Step 1 systematically devalues educational content not evaluated on the exam, and the reliance on Step 1 scores almost certainly works against efforts to increase workforce diversity. Moreover, the increasing pressure of “Step 1 Mania” has negative consequences for trainee mental health and wellness.Despite the widespread use of Step 1 scores to select applicants, there are little data to correlate scores to meaningful outcomes related to patient care or clinical practice. We find the current situation untenable, and believe a necessary first step toward reform is making Step 1 a pass/fail only examination.
       
  • Machine Learning to Differentiate T2-Weighted Hyperintense Uterine
           Leiomyomas from Uterine Sarcomas by Utilizing Multiparametric Magnetic
           Resonance Quantitative Imaging Features
    • Abstract: Publication date: October 2019Source: Academic Radiology, Volume 26, Issue 10Author(s): Masataka Nakagawa, Takeshi Nakaura, Tomohiro Namimoto, Yuji Iyama, Masafumi Kidoh, Kenichiro Hirata, Yasunori Nagayama, Hideaki Yuki, Seitaro Oda, Daisuke Utsunomiya, Yasuyuki YamashitaRationale and ObjectiveUterine leiomyomas with high signal intensity on T2-weighted imaging (T2WI) can be difficult to distinguish from sarcomas. This study assessed the feasibility of using machine learning to differentiate uterine sarcomas from leiomyomas with high signal intensity on T2WI on multiparametric magnetic resonance imaging.Materials and MethodsThis retrospective study included 80 patients (50 with benign leiomyoma and 30 with uterine sarcoma) who underwent pelvic 3 T magnetic resonance imaging examination for the evaluation of uterine myometrial smooth muscle masses with high signal intensity on T2WI. We used six machine learning techniques to develop prediction models based on 12 texture parameters on T1WI and T2WI, apparent diffusion coefficient maps, and contrast-enhanced T1WI, as well as tumor size and age. We calculated the areas under the curve (AUCs) using receiver-operating characteristic analysis for each model by 10-fold cross-validation and compared these to those for two board-certified radiologists.ResultsThe eXtreme Gradient Boosting model gave the highest AUC (0.93), followed by the random forest, support vector machine, multilayer perceptron, k-nearest neighbors, and logistic regression models. Age was the most important factor for differentiation (leiomyoma 44.9 ± 11.1 years; sarcoma 58.9 ± 14.7 years; p < 0.001). The AUC for the eXtreme Gradient Boosting was significantly higher than those for both radiologists (0.93 vs 0.80 and 0.68, p = 0.03 and p < 0.001, respectively).ConclusionMachine learning outperformed experienced radiologists in the differentiation of uterine sarcomas from leiomyomas with high signal intensity on T2WI.
       
  • A Call to Action – Our Radiology Chairs Are Burning Out
    • Abstract: Publication date: October 2019Source: Academic Radiology, Volume 26, Issue 10Author(s): Jonathan B. Kruskal, Alexander Norbash
       
  • Burnout in Chairs of Academic Radiology Departments in the United States
    • Abstract: Publication date: October 2019Source: Academic Radiology, Volume 26, Issue 10Author(s): Dhakshinamoorthy Ganeshan, Wei Wei, Wei YangObjectiveWe aimed to estimate the self-reported prevalence of burnout in chairs of academic radiology departments in the United States and identify factors associated with high burnout in chairs.Materials and MethodsAn anonymous cross-sectional online survey was conducted of members of the Society of Chairs of Academic Radiology Departments. Burnout was measured using the abbreviated Maslach Burnout Inventory Human Services Survey. Associations between survey participants’ characteristics and burnout were tested using Fisher's exact test and Wilcoxon rank sum test.ResultsOf the 123 chairs invited to complete the survey, 87 responded (response rate, 71%). The mean age of the participants was 58 years. The survey respondents had an average of 9 years of experience as department chair. The average number of work hours per week was 62 hours. Four participants (5%) of the academic chairs met all three criteria for high burnout including high emotional exhaustion, high depersonalization, and low personal accomplishment. Thirty-three participants (38%) had high emotional exhaustion and/or high depersonalization score. Low professional satisfaction score, low work-life balance satisfaction score, and low chair effectiveness score were significantly associated with high burnout. High emotional exhaustion and/or high depersonalization were significantly associated with numerous professional stressors. Lack of an institutional support group for chairs and lower number of faculty members in the department were significantly associated with burnout.ConclusionA significant proportion of chairs of academic radiology departments are experiencing 1 or more symptoms of burnout. Efforts to address burnout in radiology chairs should be initiated promptly at the national, institutional, and departmental levels.
       
  • Initial Clinical Experience with Stationary Digital Breast Tomosynthesis
    • Abstract: Publication date: October 2019Source: Academic Radiology, Volume 26, Issue 10Author(s): Yueh Z. Lee, Connor Puett, Christina R. Inscoe, Beilin Jia, Connie Kim, Ruth Walsh, Sora Yoon, Suk Jung Kim, Cherie M. Kuzmiak, Donglin Zeng, Jianping Lu, Otto ZhouRationale and ObjectivesA linear array of carbon nanotube-enabled x-ray sources allows for stationary digital breast tomosynthesis (sDBT), during which projection views are collected without the need to move the x-ray tube. This work presents our initial clinical experience with a first-generation sDBT device.Materials and MethodsFollowing informed consent, women with a “suspicious abnormality” (Breast Imaging Reporting and Data System 4), discovered by digital mammography and awaiting biopsy, were also imaged by the first generation sDBT. Four radiologists participated in this paired-image study, completing questionnaires while interpreting the mammograms and sDBT image stacks. Areas under the receiver operating characteristic curve were used to measure reader performance (likelihood of correctly identifying malignancy based on pathology as ground truth), while a multivariate analysis assessed preference, as readers compared one modality to the next when interpreting diagnostically important image features.ResultsFindings from 43 women were available for analysis, in whom 12 cases of malignancy were identified by pathology. The mean areas under the receiver operating characteristic curve was significantly higher (p < 0.05) for sDBT than mammography for all breast density categories and breast thicknesses. Additionally, readers preferred sDBT over mammography when evaluating mass margins and shape, architectural distortion, and asymmetry, but preferred mammography when characterizing microcalcifications.ConclusionReaders preferred sDBT over mammography when interpreting soft-tissue breast features and were diagnostically more accurate using images generated by sDBT in a Breast Imaging Reporting and Data System 4 population. However, the findings also demonstrated the need to improve microcalcification conspicuity, which is guiding both technological and image-processing design changes in future sDBT devices.
       
  • Shear Wave Elastography (SWE) of Asymptomatic Achilles Tendons: A
           Comparison Between Semiprofessional Athletes and the Nonathletic General
           Population
    • Abstract: Publication date: October 2019Source: Academic Radiology, Volume 26, Issue 10Author(s): Timm Dirrichs, Simone Schrading, Matthias Gatz, Markus Tingart, Christiane K. Kuhl, Valentin QuackRationale and ObjectivesIt has been shown that Shear Wave Elastography (SWE) is a useful tool to evaluate tendon stiffness, e.g. in diagnosing tendinopathies, as diseased or injured tendons are intra-individually softer than healthy ones. But reference values between different population groups are still missing. The purpose of this prospective clinical study was two-fold: First, to comparatively analyse Achilles tendon stiffness between asymptomatic semiprofessional athletes and an asymptomatic nonathletic control group. Second, to evaluate specificity, with which SWE is able to predict absence of clinical symptoms in asymptomatic individuals, compared to B-mode-Ultrasound (B-US) and Power Doppler-Ultrasound (PD-US).Materials and MethodsProspective clinical study in 68 asymptomatic healthy participants, 33 (48.5%) of them semiprofessional athletes with at least five training units of running per week and 35 (51.5 %) normal nonathletic persons, asymptomatic respectively. A consecutive of 136 Achilles tendons underwent standardized multi-modal ultrasound, consisting of B-US, PD-US, and SWE (Aixplorer, Supersonic). Pathologic structural changes at B-US, increased Doppler signal PD-US and quantitative ROI-based-analysis of tendon elasticity in kilopascal (kPa) were performed in all participants. Tendon stiffness was compared intra-individually between right and left side in each participant. SWE values between athletes and nonathletes were compared by using student's t test (p < 0.05). To evaluate the ability of different sonographic modalities in predicting "absence of clinical symptoms”, specificities of B-US, PD-US, and SWE were calculated and compared among each other.ResultsMean SWE-value for Achilles tendon was 183.8 kPa (± 98 kPa) in athletes and 103.6 kPa (± 30.5 kPa) in the nonathletic control group. The difference between athletes and non-athletes was statistically significant (p < 0.001). No significant differences were found intra-individually between right and left side: athlete mean: right: 187.2 kPa (SD ± 45.2 kPa)/left: 180.4 kPa (SD 39.7 kPa); nonathlete mean: right: 105.4 kPa (SD 34.9 kPa)/left: 101.8 kPa (SD 28.9 kPa). Specificity with which asymptomatic tendons were rated as “inconspicuous” was 60.6% for B-US, 93.9% for PD-US and 96.3% for SWE.ConclusionHealthy athletes exhibit significantly higher SWE-values in Achilles tendons than healthy nonathletic participants, which means that they have significantly stiffer tendons, possibly caused by repeated training. SWE is able to measure and display these effects. These interindividual differences should be taken into consideration, especially when rating a tendon as “healthy” or “diseased”, because a “softer” tendon does not necessarily mean to be affected.
       
  • 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: October 2019Source: Academic Radiology, Volume 26, Issue 10Author(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.
       
  • The Relationship of Arterial Wall Enhancement Ratio on MRI with the Degree
           of Inflammation in a Rabbit Aneurysm Model: A Pilot Study
    • Abstract: Publication date: October 2019Source: Academic Radiology, Volume 26, Issue 10Author(s): Guang-xian Wang, Chao Xia, Jian Liu, Chun Cui, Sheng Lei, Ming-fu Gong, Li Wen, Dong ZhangRationale and ObjectivesTo identify the relationship between enhancement ratio (ER) of aneurysm walls and degrees of inflammation.Materials and MethodsTwenty-five white rabbits were used in this study; all underwent surgery to isolate the right common carotid artery (RCCA). Twenty rabbits underwent an aneurysm creation procedure, and 5 underwent a control procedure. In the aneurysm creation procedure, there was surgical exposure of the origin of RCCA and temporary occlusion with an aneurysm clip. The distal RCCA was ligated, and the trapped segment was infused with elastase for 20 minutes, after which the clip was removed. In the control procedure, the trapped segment was infused with saline. High-resolution magnetic resonance imaging was performed at weeks 2, 3, 4, and 5 after the procedure, and wall ER was calculated. After MRI, aneurysms were harvested and stained with hematoxylin-eosin. Pearson correlation analysis and scatter plots were used to evaluate the relationship between wall ER and the degree of inflammation. The relationships between the wall ER, the number of inflammatory cells and time were analyzed by linear graphs.ResultsWall ER positively correlated with inflammatory cell count of the aneurysm wall (r = 0.877, p < 0.001). The relationships between wall ER, the number of inflammatory cells, and time increased and then decreased according linear graphs.ConclusionIn this study, the aneurysm wall ER was confirmed to be associated with the degree of inflammation on the rabbit aneurysm model.
       
  • Gadoterate Meglumine Administration in Multiple Sclerosis has no Effect on
           the Dentate Nucleus and the Globus Pallidus Signal Intensities
    • Abstract: Publication date: October 2019Source: Academic Radiology, Volume 26, Issue 10Author(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.
       
  • Detection of Extraprostatic Extension of Cancer on Biparametric MRI
           Combining Texture Analysis and Machine Learning: Preliminary Results
    • Abstract: Publication date: October 2019Source: Academic Radiology, Volume 26, Issue 10Author(s): Arnaldo Stanzione, Renato Cuocolo, Sirio Cocozza, Valeria Romeo, Francesco Persico, Ferdinando Fusco, Nicola Longo, Arturo Brunetti, Massimo ImbriacoRationale and ObjectivesExtraprostatic extension of disease (EPE) has a major role in risk stratification of prostate cancer patients. Currently, pretreatment local staging is performed with MRI, while the gold standard is represented by histopathological analysis after radical prostatectomy. Texture analysis (TA) is a quantitative postprocessing method for data extraction, while machine learning (ML) employs artificial intelligence algorithms for data classification. Purpose of this study was to assess whether ML algorithms could predict histopathological EPE using TA features extracted from unenhanced MR images.Materials and MethodsIndex lesions from biparametric MRI examinations of 39 patients with prostate cancer who underwent radical prostatectomy were manually segmented on both T2-weighted images and ADC maps for TA data extraction. Combinations of different feature selection methods and ML classifiers were tested, and their performance was compared to a baseline accuracy reference.ResultsThe classifier showing the best performance was the Bayesian Network, using the dataset obtained by the Subset Evaluator feature selection method. It showed a percentage of correctly classified instances of 82%, an area under the curve of 0.88, a weighted true positive rate of 0.82 and a weighted true negative rate of 0.80.ConclusionA combined ML and TA approach appears as a feasible tool to predict histopathological EPE on biparametric MR images.
       
  • Performance of Diffusion Kurtosis Imaging Versus Diffusion Tensor Imaging
           in Discriminating Between Benign Tissue, Low and High Gleason Grade
           Prostate Cancer
    • Abstract: Publication date: October 2019Source: Academic Radiology, Volume 26, Issue 10Author(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.
       
  • The Application of a New Model-Based Iterative Reconstruction in Low-Dose
           Upper Abdominal CT
    • Abstract: Publication date: October 2019Source: Academic Radiology, Volume 26, Issue 10Author(s): Yongjun Jia, Bingying Zhai, Taiping He, Yong Yu, Nan Yu, Haifeng Duan, Chuangbo Yang, Xirong ZhangRationale and ObjectivesTo compare upper abdominal computed tomography (CT) image quality of new model-based iterative reconstruction (MBIR) with low-contrast resolution preference (MBIRNR40), conventional MBIR (MBIRc), and adaptive statistical iterative reconstruction (ASIR) at low dose with ASIR at routine-dose.Materials and MethodsStudy included phantom and 60 patients who had initial and follow-up CT scans. For patients, the delay phase was acquired at routine-dose (noise index = 10 HU) for the initial scan and low dose (noise index = 20 HU) for the follow-up. The low-dose CT was reconstructed with 40% and 60% ASIR, MBIRc, and MBIRNR40, while routine-dose CT was reconstructed with 40% ASIR. CT value and noise measurements of the subcutaneous fat, back muscle, liver, and spleen parenchyma were compared using one-way ANOVA. Two radiologists used semiquantitative 7-scale (−3 to +3) to rate image quality and artifacts.ResultsThe phantom study revealed superior low-contrast resolution with MBIRNR40. For patient scans, the CT dose index for the low-dose CT was 3.00 ± 1.32 mGy, 75% lower than the 11.90 ± 4.75 mGy for the routine-dose CT. Image noise for the low-dose MBIRNR40 images was significantly lower than the low-dose MBIRc and ASIR images, and routine-dose ASIR images (p < 0.05). Subjective ratings showed higher image quality for low-dose MBIRNR40, with lower noise, better low-contrast resolution for abdominal structures, and finer lesion contours than those of low-dose MBIRc and ASIR images, and routine-dose ASIR images (p < 0.05).ConclusionMBIRNR40 with low-contrast resolution preference provides significantly lower noise and better image quality than MBIRc and ASIR in low-dose abdominal CT; significantly better objective and subjective image quality than the routine-dose ASIR with 75% dose reduction.
       
  • Impact of the Intima Dynamic Motion in Type B Acute Aortic Dissection on
           Renal Injury: Quantificationally Assessed by Dose-Regulated Retrospective
           ECG-Gated Dual-Source CT Angiography
    • Abstract: Publication date: October 2019Source: Academic Radiology, Volume 26, Issue 10Author(s): Shuo Zhao, Hui Gu, Yanhua Duan, Zhaoping Cheng, Baojin Chen, Shifeng Yang, Ximing WangBackgroundLittle is known about the influence of intima dynamic motion on organ ischemia and related outcomes. The purpose of this study is to quantitatively evaluate intima oscillation by CT angiography (CTA), determine its impact on acute kidney injury (AKI) in patients with type B acute aortic dissection (TB-AAD) before thoracic endovascular aortic repair (TEVAR), and further analyze its association with early adverse events postoperatively.MethodsTotally, 108 patients with TB-AAD who underwent retrospective ECG-gated CTA and received TEVAR were enrolled. Patients were divided into AKI and non-AKI groups. Area of the true lumen (TLA) was computed at R–R intervals at the upper level of kidney vessel origin every 5% step from 0% to 95%. Additionally, other morphologic parameters that have been identified as risk predictors for adverse events in uncomplicated TB-AAD were evaluated.ResultsForty-three (39.8%) patients were sorted into the AKI group. Patients with AKI exhibited a larger value for the relative change of TLA (Crel-TLA) than patients in the non-AKI group (p < 0.001), as well as a larger maximum diameter of the descending aorta (p = 0.023) and the primary entry tear (p = 0.012). Crel-TLA and elevated systolic blood pressure were independent predictors of AKI. Patients with Crel-TLA ≥ 42.6% were associated with a high incidence of renal ischemia before TEVAR and early adverse events postoperatively (all p < 0.001).ConclusionIntima dynamic motion, as quantitatively evaluated by CTA, has a significant influence on renal injury before and after the aortic intervention, as well as other adverse events, which might guide clinical therapy in high-risk patients.
       
  • Comparison of Nongated Chest CT and Dedicated Calcium Scoring CT for
           Coronary Calcium Quantification Using a 256-Dector Row CT Scanner
    • Abstract: Publication date: October 2019Source: Academic Radiology, Volume 26, Issue 10Author(s): Yuhuan Chen, Zhijun Hu, Michelle Li, Yongjun Jia, Taiping He, Zhentang Liu, Donghong Wei, Yong YuBackgroundCoronary artery calcification (CAC) is a marker of atherosclerosis and an independent risk factor for cardiac-related mortality and frequently detected on noncontrast chest CT. We aimed to investigate the reliability and accuracy of determining CAC using noncontrast, nongated chest CT with 256-detector row.Materials and MethodsA total of 1318 patients for chest examination were enrolled to undergo both nongated chest CT and dedicated calcium-scoring CT (CSCT) on a 256-detector row CT scanner. The chest CT was scanned in fast-helical mode with 8 cm collimation, 0.28 second rotation speed and pitch 0.992:1 to cover entire chest. CSCT used single prospective ECG-triggered cardiac axial mode with 0.28 second rotation speed covering only the heart. CAC scores (Agatston, mass, and volume) were determined using both image sets and were statistically compared.ResultsSensitivity and specificity of nongated chest CT for determining positive CAC was 94.8% (182/192) and 100%, respectively. The agreement in assessing the quantitative Agatston, volume, and mass scores between the nongated chest CT and CSCT was almost perfect, with the intraclass correlation coefficient values of 0.998, 0.999, and 0.999, respectively. Additionally, there was a good agreement in CAC quantification between the nongated chest CT and dedicated CSCT with small coefficient of variation: mass score (9.0%), volume score (9.5%), and Agatston score (12.6%).ConclusionNongated chest CT with 256-detector row is a reliable imaging mode for detecting and quantifying calcifications in coronary arteries compared with dedicated calcium-scoring CT.
       
  • Detection of Pulmonary Embolism Based on Reduced Changes in Radiographic
           Lung Density During Cardiac Beating Using Dynamic Flat-panel Detector: An
           Animal-based Study
    • Abstract: Publication date: October 2019Source: Academic Radiology, Volume 26, Issue 10Author(s): Rie Tanaka, Tohru Tani, Norihisa Nitta, Takahisa Tabata, Noritsugu Matsutani, Shintaro Muraoka, Tsutomu Yoneyama, Shigeru SanadaRationale and ObjectivesTo assess the capacity of dynamic flat-panel detector imaging without the use of contrast media to detect pulmonary embolism (PE) based on temporal changes in radiographic lung density during cardiac beating.Materials and MethodsSequential chest radiographs of six pigs were acquired using a dynamic flat-panel detector system. A porcine model of PE was developed, and temporal changes in pixel values in the imaged lungs were analyzed during a whole cardiac cycle. Mean differences in temporal changes in pixel values between affected and unaffected lobes were assessed using the paired t test. To facilitate visual evaluation, temporal changes in pixel values were depicted using a colorimetric scale and were compared to the findings of contrast-enhanced images.ResultsAffected lobes exhibited a mean reduction of 49.6% in temporal changes in pixel values compared to unaffected lobes within the same animals, and a mean reduction of 41.3% compared to that before vessel blockage in the same lobe. All unaffected lobes exhibited significantly-increased changes in pixel values after vessel blockage (p < 0.01). In all PE models, there were color-deficient areas with shapes and locations that matched well with the perfusion defects confirmed in the corresponding contrast-enhanced images.ConclusionDynamic chest radiography enables the detection of perfusion defects in the lobe unit based on temporal changes in image density, even without the use of contrast media. Quantification and visualization techniques provide a better understanding of the circulation-induced changes depicted in dynamic chest radiographs.
       
  • Development and Validation of a MRI-Based Radiomics Prognostic Classifier
           in Patients with Primary Glioblastoma Multiforme
    • Abstract: Publication date: October 2019Source: Academic Radiology, Volume 26, Issue 10Author(s): Xin Chen, Mengjie Fang, Di Dong, Lingling Liu, Xiangdong Xu, Xinhua Wei, Xinqing Jiang, Lei Qin, Zaiyi LiuRationale and ObjectivesGlioblastoma multiforme (GBM) is the most common and deadly type of primary malignant tumor of the central nervous system. Accurate risk stratification is vital for a more personalized approach in GBM management. The purpose of this study is to develop and validate a MRI-based prognostic quantitative radiomics classifier in patients with newly diagnosed GBM and to evaluate whether the classifier allows stratification with improved accuracy over the clinical and qualitative imaging features risk models.MethodsClinical and MR imaging data of 127 GBM patients were obtained from the Cancer Genome Atlas and the Cancer Imaging Archive. Regions of interest corresponding to high signal intensity portions of tumor were drawn on postcontrast T1-weighted imaging (post-T1WI) on the 127 patients (allocated in a 2:1 ratio into a training [n = 85] or validation [n = 42] set), then 3824 radiomics features per patient were extracted. The dimension of these radiomics features were reduced using the minimum redundancy maximum relevance algorithm, then Cox proportional hazard regression model was used to build a radiomics classifier for predicting overall survival (OS). The value of the radiomics classifier beyond clinical (gender, age, Karnofsky performance status, radiation therapy, chemotherapy, and type of resection) and VASARI features for OS was assessed with multivariate Cox proportional hazards model. Time-dependent receiver operating characteristic curve analysis was used to assess the predictive accuracy.ResultsA classifier using four post-T1WI-MRI radiomics features built on the training dataset could successfully separate GBM patients into low- or high-risk group with a significantly different OS in training (HR, 6.307 [95% CI, 3.475-11.446]; p < 0.001) and validation set (HR, 3.646 [95% CI, 1.709–7.779]; p < 0.001). The area under receiver operating characteristic curve of radiomics classifier (training, 0.799; validation, 0.815 for 12-month) was higher compared to that of the clinical risk model (Karnofsky performance status, radiation therapy; training, 0.749; validation, 0.670 for 12-month), and none of the qualitative imaging features was associated with OS. The predictive accuracy was further improved when combined the radiomics classifier with clinical data (training, 0.819; validation: 0.851 for 12-month).ConclusionA classifier using radiomics features allows preoperative prediction of survival and risk stratification of patients with GBM, and it shows improved performance compared to that of clinical and qualitative imaging features models.
       
  • Lung Cancer Screening with Low-Dose CT: Baseline Screening Results in
           Shanghai
    • Abstract: Publication date: October 2019Source: Academic Radiology, Volume 26, Issue 10Author(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.
       
  • Life Imitates Art
    • Abstract: Publication date: October 2019Source: Academic Radiology, Volume 26, Issue 10Author(s): N. Reed Dunnick
       
  • The Power of Design Thinking in Medical Education
    • Abstract: Publication date: October 2019Source: Academic Radiology, Volume 26, Issue 10Author(s): Lori A. Deitte, Reed A. OmaryA goal of medical education should be to optimize educational experiences of our learners. How can we better understand their experiences and design educational activities that inspire them to learn' Design Thinking is a powerful process that consists of five iterative phases: empathize, define, ideate, prototype, and test. Empathy with the user experience is at the core of Design Thinking. This helps define the right problem so that the right solutions can be developed. In this article, we share our experiences with using Design Thinking in radiology education. As educators, we are constantly learning and innovating. Design Thinking provides a powerful process and a growth mindset to help develop creative solutions as we move forward. We invite you to join us in this discovery quest for innovative solutions in medical education through the Design Thinking process.
       
  • Reply to the USMLE Step 1 Pass/Fail Reporting Proposal: Another Opinion
    • Abstract: Publication date: Available online 22 August 2019Source: Academic RadiologyAuthor(s): J. Bryan Carmody, David S. Sarkany, Darel E. Heitkamp
       
  • The USMLE Step 1 Pass/Fail Reporting Proposal: Another Opinion
    • Abstract: Publication date: Available online 22 August 2019Source: Academic RadiologyAuthor(s): Absia Jabbar, Shahzaib Nabi, Khurram Shafique, Adeel Arshad
       
  • Diagnostic Accuracy of Noncontrast Self-navigated Free-Breathing MR
           Angiography Versus CT Angiography: A Prospective Study in Pediatric
           Patients with Suspected Anomalous Coronary Arteries
    • Abstract: Publication date: Available online 19 August 2019Source: Academic RadiologyAuthor(s): Maryam Ghadimi Mahani
       
  • Educating Learners about the Pros and Cons of Telework
    • Abstract: Publication date: Available online 14 August 2019Source: Academic RadiologyAuthor(s):
       
  • The USMLE Step 1 Pass/Fail Reporting Proposal: The APDR Position
    • Abstract: Publication date: Available online 2 August 2019Source: Academic RadiologyAuthor(s): Anna Rozenshtein, Mark E. Mullins, M. Victoria MarxBackgroundThe National Board of Medical Examiners (NBME) and the United States Medical Licensing Examination (USMLE) has convened a conference of “key stakeholders” on March 11–12, 2019 to consider reporting the results of the USMLE Step 1 as pass/fail.DiscussionWhile the original purpose of the USMLE Step 1 was to provide an objective basis for medical licensing, the score is increasingly used in residency applicant screening and selection because it is an objective, nationally recognized metric allowing comparison across medical schools in and outside the United States. Excessive reliance on the Step 1 score in the matching process has led to “Step 1 Culture” that drives medical schools to “teach to the test,” increases medical student anxiety, and disadvantages minorities that have been shown to score lower on the USMLE Step 1 examination.The outsize role of the USMLE Step 1 score in resident selection is due to lack of standardization in medical school transcripts, grade inflation, and the lack of class standing in many summative assessments. Furthermore, the numeric score allows initial Electronic Residency Application Service filtering, commonly used by programs to limit the number of residency applications to review.ConclusionThe Association of Program Directors in Radiology (APDR) is concerned that pass/fail reporting of the USMLE Step 1 score would take away an objective measure of medical student's knowledge and the incentive to acquire as much of it as possible. Although the APDR is not in favor of the Step 1 exam being used as a screening tool, in the absence of an equal or better metric for applicant comparison the APDR opposes the change in Step 1 reporting from the numeric score to pass/fail.
       
 
 
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