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Journal Cover Ultrasound in Medicine & Biology
  [SJR: 0.939]   [H-I: 91]   [6 followers]  Follow
    
   Full-text available via subscription Subscription journal
   ISSN (Print) 0301-5629
   Published by Elsevier Homepage  [2970 journals]
  • Evaluation of Gastric Volumes: Comparison of 3-D Ultrasound and Magnetic
           Resonance Imaging
    • Abstract: Publication date: Available online 8 April 2016
      Source:Ultrasound in Medicine & Biology
      Author(s): Wijnand J. Buisman, Femke A. Mauritz, Wouter E. Westerhuis, Odd Helge Gilja, David C. van der Zee, Maud Y.A. van Herwaarden-Lindeboom
      To investigate gastric accommodation, accurate measurements of gastric volumes are necessary. An excellent technique to measure gastric volumes is dynamic magnetic resonance imaging (MRI). Unfortunately, dynamic MRI is expensive and not always available. A new 3-D ultrasound (US) method using a matrix transducer was developed to measure gastric volumes. In this prospective study, 14 healthy volunteers underwent a dynamic MRI and a 3-D US. Gastric volumes were calculated with intra-gastric liquid content and total gastric volume. Mean postprandial liquid gastric content was 397 ± 96.5 mL. Mean volume difference was 1.0 mL with limits of agreement of −8.9 to 10.9 mL. When gastric air was taken into account, mean total gastric volume was 540 ± 115.4 mL SD. Mean volume difference was 2.3 mL with limits of agreement of −21.1 to 26.4 mL. The matrix 3-D US showed excellent agreement with dynamic MRI. Therefore matrix 3-D US is a reliable alternative to measure gastric volumes.


      PubDate: 2016-04-09T06:38:50Z
       
  • A New Method for Discriminating between Bronchial and Pulmonary Arterial
           Phases using Contrast-enhanced Ultrasound
    • Abstract: Publication date: Available online 8 April 2016
      Source:Ultrasound in Medicine & Biology
      Author(s): Zhang Hong-xia, He Wen, Cheng Ling-gang, Cai Wen-jia, Li Shuo, Du Li-juan, Song Hai-man, Zhao Yang
      This study aimed to explore the value of a real-time comparative observation method using contrast-enhanced ultrasound (CEUS) for discriminating between bronchial and pulmonary arterial phases in diagnosing lung diseases. Forty-nine patients with 50 pulmonary lesions (45 peripheral lesions and five central lesions with obstructive atelectasis, including 36 malignant tumors, five tuberculomas, four inflammatory pseudotumors and five pneumonia lesions) detected via computed tomography and visible on ultrasonography were enrolled in this study. The arterial phases were determined by comparing contrast agent arrival time (AT) in the peripheral lung lesion with that in adjacent lung tissue, referred to as a real-time comparative observation method. Detection rates of this observation method were 100% (50/50) for pulmonary arterial phase and 88% (44/50) for bronchial arterial phase. Using the instrument's built-in graphing and analysis software, a time-intensity curve was constructed based on a chosen region of interest within the lesion where enhancement was the most obvious. Commonly used perfusion indicators in CEUS, such as AT, time-to-peak and peak intensity, were obtained from the time-intensity curve. Percutaneous puncture biopsies were performed under ultrasound guidance, and specimens of all 50 lesions were examined pathologically. AT was significantly shorter in patients with pneumonia than in those with malignant tumors or chronic inflammation (p < 0.05), whereas no difference was seen between those with malignant tumors and those with chronic inflammation. No significant differences in time-to-peak or peak intensity were seen among those with various lung diseases (p > 0.05). This is the first description of a real-time comparative observation method using CEUS for determining the arterial phases in the lungs. This method is accurate, simple to perform and provides a direct display. It is expected to become a practical and feasible tool for diagnosing lung diseases.


      PubDate: 2016-04-09T06:38:50Z
       
  • Diagnosis of Columnar Cell Lesions and Atypical Ductal Hyperplasia by
           Ultrasound-Guided Core Biopsy: Findings Associated with Underestimation of
           Breast Carcinoma
    • Abstract: Publication date: Available online 8 April 2016
      Source:Ultrasound in Medicine & Biology
      Author(s): Hye Shin Ahn, Mijung Jang, Sun Mi Kim, Bo La Yun, Sung-Won Kim, Eun Young Kang, So Yeon Park
      The aim of the study described here was to determine underestimation rates and identify radiologic predictors of underestimation for columnar cell lesions (CCLs) and atypical ductal hyperplasia (ADH) detected by ultrasound-guided core needle biopsy. A total of 103 CCLs and ADH lesions in 100 patients diagnosed by ultrasound-guided core needle biopsy were evaluated. Breast sonographic and mammographic findings were reviewed, and underestimation rates were determined by surgical excision, percutaneous vacuum-assisted excision or 2-y imaging follow-up. All underestimated lesions were ductal carcinoma in situ, and the underestimation rates of flat epithelial atypia (FEA), FEA + ADH and ADH were 5.9% (1/17), 44.4% (4/9) and 27.3% (12/44), respectively. There was no underestimation of CCLs without atypia. The presence of calcifications on ultrasound was significantly associated with underestimation (p = 0.010). Therefore, except for CCLs without atypia, all other lesions may require excision, especially when calcification is present on ultrasound or when FEA + ADH is found.


      PubDate: 2016-04-09T06:38:50Z
       
  • Ultrasound Effect on Cancerous versus Non-cancerous Cells
    • Abstract: Publication date: Available online 8 April 2016
      Source:Ultrasound in Medicine & Biology
      Author(s): Aharon Azagury, Eliz Amar-Lewis, Yana Yudilevitch, Carol Isaacson, Brenda Laster, Joseph Kost
      Previous studies have found that cancer cells whose metastatic potential is low are more vulnerable to mechanical stress-induced trauma to their cytoskeleton compared with benign cells. Because ultrasound induces mechanical stresses on cells and tissues, it is postulated that there may be a way to apply ultrasound to tumors to reduce their ability to metastasize. The difference between low-malignant-potential cancer cells and benign cells could be a result of their different responses to the mechanical stress insonation induced. This hypothesis was tested in vitro and in vivo. Low-malignant-potential cells were found to be more sensitive to insonation, resulting in a significantly higher mortality rate compared with that of benign cells, 89% versus 21%, respectively. This effect can be controlled by varying ultrasound parameters: intensity, duration, and duty cycle. Thus, the results presented in this study suggest the application of ultrasound to discriminate between benign and malignant cells.


      PubDate: 2016-04-09T06:38:50Z
       
  • Ultrasound Contrast Plane Wave Imaging Based on Bubble Wavelet Transform:
           In Vitro and In Vivo Validations
    • Abstract: Publication date: Available online 7 April 2016
      Source:Ultrasound in Medicine & Biology
      Author(s): Diya Wang, Yujin Zong, Xuan Yang, Hong Hu, Jinjin Wan, Lei Zhang, Ayache Bouakaz, Mingxi Wan
      The aim of the study described here was to develop an ultrasound contrast plane wave imaging (PWI) method based on pulse-inversion bubble wavelet transform imaging (PIWI) to improve the contrast-to-tissue ratio of contrast images. A pair of inverted “bubble wavelets” with plane waves was constructed according to the modified Herring equation. The original echoes were replaced by the maximum wavelet correlation coefficients obtained from bubble wavelet correlation analysis. The echoes were then summed to distinguish microbubbles from tissues. In in vivo experiments on rabbit kidney, PIWI improved the contrast-to-tissue ratio of contrast images up to 4.5 ± 1.5 dB, compared with that obtained in B-mode (p < 0.05), through use of a pair of inverted plane waves. The disruption rate and infusion time of microbubbles in PIWI-based PWI were then quantified using two perfusion parameters, area under the curve and half transmit time estimated from time–intensity curves, respectively. After time–intensity curves were denoised by detrended fluctuation analysis, the average area under the curve and half transit time of PIWI-based PWI were 55.94% (p < 0.05) and 20.51% (p < 0.05) higher than those of conventional focused imaging, respectively. Because of its high contrast-to-tissue ratio and low disruption of microbubbles, PIWI-based PWI has a long infusion time and is therefore beneficial for transient monitoring and perfusion assessment of microbubbles circulating in vessels.


      PubDate: 2016-04-08T06:38:30Z
       
  • Heterogeneous Tissue Characterization Using Ultrasound: A Comparison of
           Fractal Analysis Backscatter Models on Liver Tumors
    • Abstract: Publication date: Available online 5 April 2016
      Source:Ultrasound in Medicine & Biology
      Author(s): Omar S. Al-Kadi, Daniel Y.F. Chung, Constantin C. Coussios, J. Alison Noble
      Assessment of tumor tissue heterogeneity via ultrasound has recently been suggested as a method for predicting early response to treatment. The ultrasound backscattering characteristics can assist in better understanding the tumor texture by highlighting the local concentration and spatial arrangement of tissue scatterers. However, it is challenging to quantify the various tissue heterogeneities ranging from fine to coarse of the echo envelope peaks in tumor texture. Local parametric fractal features extracted via maximum likelihood estimation from five well-known statistical model families are evaluated for the purpose of ultrasound tissue characterization. The fractal dimension (self-similarity measure) was used to characterize the spatial distribution of scatterers, whereas the lacunarity (sparsity measure) was applied to determine scatterer number density. Performance was assessed based on 608 cross-sectional clinical ultrasound radiofrequency images of liver tumors (230 and 378 representing respondent and non-respondent cases, respectively). Cross-validation via leave-one-tumor-out and with different k-fold methodologies using a Bayesian classifier was employed for validation. The fractal properties of the backscattered echoes based on the Nakagami model (Nkg) and its extend four-parameter Nakagami-generalized inverse Gaussian (NIG) distribution achieved best results—with nearly similar performance—in characterizing liver tumor tissue. The accuracy, sensitivity and specificity of Nkg/NIG were 85.6%/86.3%, 94.0%/96.0% and 73.0%/71.0%, respectively. Other statistical models, such as the Rician, Rayleigh and K-distribution, were found to not be as effective in characterizing subtle changes in tissue texture as an indication of response to treatment. Employing the most relevant and practical statistical model could have potential consequences for the design of an early and effective clinical therapy.


      PubDate: 2016-04-08T06:38:30Z
       
  • Quantification of Very Low Concentrations of Leukocyte Suspensions
           In Vitro by High-Frequency Ultrasound
    • Abstract: Publication date: Available online 7 April 2016
      Source:Ultrasound in Medicine & Biology
      Author(s): Xavier Jimenez, Shiva K. Shukla, Isabel Ortega, Francisco J. Illana, Carlos Castro-González, Berta Marti-Fuster, Ian Butterworth, Manuel Arroyo, Brian Anthony, Luis Elvira
      Accurate measurement of very low cerebrospinal fluid (CSF) white blood cell (WBC) concentration is key to the diagnosis of bacterial meningitis, lethal if not promptly treated. Here we show that high frequency ultrasound (HFUS) can detect CSF WBC in vitro in concentrations relevant to meningitis diagnosis with a much finer precision than gold standard manual counting in a Fuchs-Rosenthal chamber. WBC concentrations in a mock CSF model, in the range 0–50 WBC/μL, have been tested and compared to gold standard ground truth. In this range, excellent agreement (Cohen's kappa [κ] = 0.78–90) (Cohen 1960) was observed between HFUS and the gold standard method. The presented experimental set-up allowed us to detect WBC concentrations as low as 2 cells/μL. HFUS shows promise as a low-cost, reliable and automated technology to measure very low CSF WBC concentrations for the diagnosis of early meningitis.


      PubDate: 2016-04-08T06:38:30Z
       
  • Reproducibility of Brachial Vascular Changes with Alterations in End-Tidal
           Carbon Dioxide
    • Abstract: Publication date: Available online 6 April 2016
      Source:Ultrasound in Medicine & Biology
      Author(s): Justin R. Geijer, Nicholas G. Evanoff, Aaron S. Kelly, Michael A. Chernin, Matthew G. Stoltman, Donald R. Dengel
      The purpose of this study was to examine the reproducibility of the peripheral vascular response to hypercapnia. Healthy college-aged men (n = 7) and women (n = 10) underwent an iso-oxic 10-mm Hg increase in PetCO2 for 12 min. Brachial artery diameter changes were measured using ultrasound imaging. Two tests were completed on day 1 with 15 min of rest between tests. Tests were repeated on day 2. Paired t-tests, Bland–Altman plots and intra-class correlations (ICCs) determined reproducibility. There were no significant differences in peak dilation within day (5.33 ± 3.73% vs. 4.52 ± 2.49%, p = 0.378). The within-day ICC was poor (0.213). Within-day time-to-peak dilation did not significantly differ (660.0 ± 231.8 s vs. 602.7 ± 259.9 s, p = 0.379), and the ICC was fair (0.416, p = 0.113). Between-day peak dilation did not significantly differ (5.24 ± 3.84% vs. 4.71 ± 3.17%, p = 0.123), and the ICC was fair (0.419). Hypercapnia-induced brachial artery dilation is similar within day and between days. The ICC for peak dilation suggests the methodology is not reproducible.


      PubDate: 2016-04-08T06:38:30Z
       
  • Use of Contrast-Enhanced Ultrasonography to Evaluate Chronic
           Allograft Nephropathy in Rats and Correlations between Time-Intensity
           Curve Parameters and Allograft Fibrosis
    • Abstract: Publication date: Available online 5 April 2016
      Source:Ultrasound in Medicine & Biology
      Author(s): Qiang Zhang, Zexing Yu, Yue Xu, Song Zeng, Zijian Zhang, Wenrui Xue, Wei Wang, Xiaodong Zhang, Xiaopeng Hu
      This study quantitatively analyzed changes in the hemodynamic characteristics of renal allografts at different stages in a rat chronic allograft nephropathy (CAN) model as well as the relationship between hemodynamic parameters and renal allograft fibrosis using contrast-enhanced ultrasonography (CEUS). The experimental group used a CAN rat model (n = 30), and the control group used an orthotopic syngeneic renal transplant model (n = 30). After surgery, creatinine clearance rates were regularly monitored every 2 wk. The checking times were set at 4, 12 and 24 wk after surgery, which represent early, middle and late stage of CAN, respectively. At different stages of CAN, eight rats from each group were randomly selected for CEUS examination. Time-intensity curve (TIC) parameters, including rise time, peak intensity, mean transit time, area under the curve, wash-in slope, time-to-peak and α-smooth muscle actin (α-SMA) expression; Vimentin expression; and chronic allograft damage index scores were evaluated by linear correlation analysis. Before the creatinine clearance rate showed significant abnormalities, the renal allografts in the experimental group had already presented pathologic changes associated with CAN. In the early stage after surgery, compared to the TIC curve of the control group, the experimental group showed increased rise time, mean transit time, area under the curve and time-to-peak, and decreased wash-in slope (p < 0.05). Chronic allograft damage index scores and the expression levels of α-SMA and Vimentin proteins in renal allografts were correlated with TIC parameters (p < 0.05). Compared to creatinine clearance rate, CEUS can detect CAN at earlier stages. The correlations between TIC-related parameters and the expression levels of α-SMA and Vimentin in renal allografts indicate that CEUS is a feasible way to assess the degree of renal allograft fibrosis quantitatively.


      PubDate: 2016-04-08T06:38:30Z
       
  • Improvement of Shear Wave Motion Detection Using Harmonic Imaging in
           Healthy Human Liver
    • Abstract: Publication date: May 2016
      Source:Ultrasound in Medicine & Biology, Volume 42, Issue 5
      Author(s): Carolina Amador, Pengfei Song, Duane D. Meixner, Shigao Chen, Matthew W. Urban
      Quantification of liver elasticity is a major application of shear wave elasticity imaging (SWEI) to non-invasive assessment of liver fibrosis stages. SWEI measurements can be highly affected by ultrasound image quality. Ultrasound harmonic imaging has exhibited a significant improvement in ultrasound image quality as well as for SWEI measurements. This was previously illustrated in cardiac SWEI. The purpose of this study was to evaluate liver shear wave particle displacement detection and shear wave velocity (SWV) measurements with fundamental and filter-based harmonic ultrasound imaging. In a cohort of 17 patients with no history of liver disease, a 2.9-fold increase in maximum shear wave displacement, a 0.11 m/s decrease in the overall interquartile range and median SWV and a 17.6% increase in the success rate of SWV measurements were obtained when filter-based harmonic imaging was used instead of fundamental imaging.


      PubDate: 2016-03-26T04:45:58Z
       
  • Erratum to: “Trans-stent B-mode Ultrasound and Passive Cavitation
           Imaging” in Ultrasound Med Biol 2016;42(2):518–527.
    • Abstract: Publication date: May 2016
      Source:Ultrasound in Medicine & Biology, Volume 42, Issue 5
      Author(s): Kevin J. Haworth, Jason L. Raymond, Kirthi Radhakrishnan, Melanie R. Moody, Shao-ling Huang, Tao Peng, Himanshu Shekhar, Melvin E. Klegerman, Hyunggun Kim, David D. McPherson, Christy K. Holland



      PubDate: 2016-03-26T04:45:58Z
       
  • Calendar
    • Abstract: Publication date: May 2016
      Source:Ultrasound in Medicine & Biology, Volume 42, Issue 5




      PubDate: 2016-03-26T04:45:58Z
       
  • A New Class of Phantom Materials for Poroelastography Imaging Techniques
    • Abstract: Publication date: May 2016
      Source:Ultrasound in Medicine & Biology, Volume 42, Issue 5
      Author(s): Anuj Chaudhry, Iman K. Yazdi, Rohit Kongari, Ennio Tasciotti, Raffaella Righetti
      Poroelastography is an elastographic technique used to image the temporal mechanical behavior of tissues. One of the major challenges in determining experimental potentials and limitations of this technique has been the lack of complex and realistic controlled phantoms that could be used to corroborate the limited number of theoretical and simulation studies available in the literature as well as to predict its performance in complex experimental situations and in a variety of conditions. In the study described here, we propose and analyze a new class of phantom materials for temporal elastography imaging. The results indicate that, by using polyacrylamide, we can generate inhomogeneous elastographic phantoms with controlled fluid content and fluid flow properties, while maintaining mechanical and ultrasonic properties similar to those of soft tissues.


      PubDate: 2016-03-26T04:45:58Z
       
  • A Broadband Polyvinylidene Difluoride-Based Hydrophone with Integrated
           Readout Circuit for Intravascular Photoacoustic Imaging
    • Abstract: Publication date: May 2016
      Source:Ultrasound in Medicine & Biology, Volume 42, Issue 5
      Author(s): Verya Daeichin, Chao Chen, Qing Ding, Min Wu, Robert Beurskens, Geert Springeling, Emile Noothout, Martin D. Verweij, Koen W.A. van Dongen, Johan G. Bosch, Antonius F.W. van der Steen, Nico de Jong, Michiel Pertijs, Gijs van Soest
      Intravascular photoacoustic (IVPA) imaging can visualize the coronary atherosclerotic plaque composition on the basis of the optical absorption contrast. Most of the photoacoustic (PA) energy of human coronary plaque lipids was found to lie in the frequency band between 2 and 15 MHz requiring a very broadband transducer, especially if a combination with intravascular ultrasound is desired. We have developed a broadband polyvinylidene difluoride (PVDF) transducer (0.6 × 0.6 mm, 52 μm thick) with integrated electronics to match the low capacitance of such a small polyvinylidene difluoride element (<5 pF/mm2) with the high capacitive load of the long cable (∼100 pF/m). The new readout circuit provides an output voltage with a sensitivity of about 3.8 μV/Pa at 2.25 MHz. Its response is flat within 10 dB in the range 2 to 15 MHz. The root mean square (rms) output noise level is 259 μV over the entire bandwidth (1–20 MHz), resulting in a minimum detectable pressure of 30 Pa at 2.25 MHz.


      PubDate: 2016-03-26T04:45:58Z
       
  • Changes in Dorsal Neck Muscle Function in Individuals with Chronic
           Whiplash-Associated Disorders: A Real-Time Ultrasound Case–Control
           Study
    • Abstract: Publication date: May 2016
      Source:Ultrasound in Medicine & Biology, Volume 42, Issue 5
      Author(s): Gunnel Peterson, David Nilsson, Simon Peterson, Åsa Dedering, Johan Trygg, Thorne Wallman, Anneli Peolsson
      Impaired neck muscle function leads to disability in individuals with chronic whiplash-associated disorder (WAD), but diagnostic tools are lacking. In this study, deformations and deformation rates were investigated in five dorsal neck muscles during 10 arm elevations by ultrasonography with speckle tracking analyses. Forty individuals with chronic WAD (28 women and 12 men, mean age = 37 y) and 40 healthy controls matched for age and sex were included. The WAD group had higher deformation rates in the multifidus muscle during the first (p < 0.04) and 10th (only women, p < 0.01) arm elevations compared with the control group. Linear relationships between the neck muscles for deformation rate (controls: R 2 = 0.24–0.82, WAD: R 2 = 0.05–0.74) and deformation of the deepest muscles (controls: R 2 = 0.61–0.32, WAD: R 2 = 0.15–0.01) were stronger for women in the control group versus women with WAD, indicating there is altered interplay between dorsal neck muscles in chronic WAD.


      PubDate: 2016-03-26T04:45:58Z
       
  • Development and Validation of a Method to Measure Lumbosacral Motion Using
           Ultrasound Imaging
    • Abstract: Publication date: May 2016
      Source:Ultrasound in Medicine & Biology, Volume 42, Issue 5
      Author(s): Wolbert van den Hoorn, Michel W. Coppieters, Jaap H. van Dieën, Paul W. Hodges
      The study aim was to validate an ultrasound imaging technique to measure sagittal plane lumbosacral motion. Direct and indirect measures of lumbosacral angle change were developed and validated. Lumbosacral angle was estimated by the angle between lines through two landmarks on the sacrum and lowest lumbar vertebrae. Distance measure was made between the sacrum and lumbar vertebrae, and angle was estimated after distance was calibrated to angle. This method was tested in an in vitro spine and an in vivo porcine spine and validated to video and fluoroscopy measures, respectively. R 2, regression coefficients and mean absolute differences between ultrasound measures and validation measures were, respectively: 0.77, 0.982, 0.67° (in vitro, angle); 0.97, 0.992, 0.82° (in vitro, distance); 0.94, 0.995, 2.1° (in vivo, angle); and 0.95, 0.997, 1.7° (in vivo, distance). Lumbosacral motion can be accurately measured with ultrasound. This provides a basis to develop measurements for use in humans.


      PubDate: 2016-03-26T04:45:58Z
       
  • Identification of the Position and Thickness of the First Annular Pulley
           in Sonographic Images
    • Abstract: Publication date: May 2016
      Source:Ultrasound in Medicine & Biology, Volume 42, Issue 5
      Author(s): Tai-Hua Yang, Yi-Hsun Lin, Bo-I Chuang, Hsin-Chen Chen, Wei-Jr Lin, Dee-Shan Yang, Shyh-Hau Wang, Yung-Nien Sun, I-Ming Jou, Li-Chieh Kuo, Fong-Chin Su
      The purpose was to identify the A1 pulley's exact location and thickness by comparing measurements from a clinical high-frequency ultrasound scanner system (CHUS), a customized high-frequency ultrasound imaging research system (HURS) and a digital caliper. Ten cadaveric hands were used. We explored the pulley by layers, inserted guide pins and scanned it with the CHUS. After identifying the pulley, we measured each long finger's thickness using the CHUS and excised the pulley to measure its thickness with a digital caliper and the HURS. The thin hypo-echoic layer was revealed to be the synovial fluid space, and the pulley appears hyper-echoic regardless of scan direction. We also defined the pulley's boundaries. Moreover, the CHUS provided a significantly lower measurement of the pulley's thickness than the digital caliper and HURS. Likewise, based on the digital caliper's measurement, the HURS had significantly lower mean absolute and relative errors than the CHUS.


      PubDate: 2016-03-26T04:45:58Z
       
  • Ultrasound Strain Elastography in Assessment of Muscle Stiffness in Acute
           Levodopa Challenge Test: A Feasibility Study
    • Abstract: Publication date: May 2016
      Source:Ultrasound in Medicine & Biology, Volume 42, Issue 5
      Author(s): Jing Gao, Li-Juan Du, Wen He, Shuo Li, Ling-Gang Cheng
      To evaluate the feasibility of ultrasound strain elastography in assessing the response of muscle stiffness to the acute levodopa test, we prospectively performed strain elastography on the biceps brachii muscle (BBM) of 18 patients to diagnose Parkinson's disease. BBM and subcutaneous tissue strains (deformations) were produced by external compression with an ultrasound transducer and estimated using 2-D speckle tracking. We used the strain ratio (SR = BBM strain/reference strain) to assess BBM stiffness. The rate of increase in SR [rate = (SR after levodopa−SR before levodopa)/SR before levodopa] was used to assess the muscle stiffness response to levodopa. SR significantly increased after levodopa administration in 11 patients with Parkinson's disease (p = 0.02), whereas it did not in 7 patients with parkinsonian syndrome (from non-Parkinson's causes) (p = 0.14). The area under the receiver operating characteristic curve for the rate of increase in SR in determining Parkinson's disease was 0.96. The rate of increase in SR seems to be feasible in evaluating the effect of levodopa on muscle stiffness in the diagnosis of Parkinson's disease.


      PubDate: 2016-03-26T04:45:58Z
       
  • Breast Density Analysis with Automated Whole-Breast Ultrasound: Comparison
           with 3-D Magnetic Resonance Imaging
    • Abstract: Publication date: May 2016
      Source:Ultrasound in Medicine & Biology, Volume 42, Issue 5
      Author(s): Jeon-Hor Chen, Yan-Wei Lee, Si-Wa Chan, Dah-Cherng Yeh, Ruey-Feng Chang
      In this study, a semi-automatic breast segmentation method was proposed on the basis of the rib shadow to extract breast regions from 3-D automated whole-breast ultrasound (ABUS) images. The density results were correlated with breast density values acquired with 3-D magnetic resonance imaging (MRI). MRI images of 46 breasts were collected from 23 women without a history of breast disease. Each subject also underwent ABUS. We used Otsu's thresholding method on ABUS images to obtain local rib shadow information, which was combined with the global rib shadow information (extracted from all slice projections) and integrated with the anatomy's breast tissue structure to determine the chest wall line. The fuzzy C-means classifier was used to extract the fibroglandular tissues from the acquired images. Whole-breast volume (WBV) and breast percentage density (BPD) were calculated in both modalities. Linear regression was used to compute the correlation of density results between the two modalities. The consistency of density measurement was also analyzed on the basis of intra- and inter-operator variation. There was a high correlation of density results between MRI and ABUS (R 2 = 0.798 for WBV, R 2 = 0.825 for PBD). The mean WBV from ABUS images was slightly smaller than the mean WBV from MR images (MRI: 342.24 ± 128.08 cm3, ABUS: 325.47 ± 136.16 cm3, p < 0.05). In addition, the BPD calculated from MR images was smaller than the BPD from ABUS images (MRI: 24.71 ± 15.16%, ABUS: 28.90 ± 17.73%, p < 0.05). The intra-operator and inter-operator variant analysis results indicated that there was no statistically significant difference in breast density measurement variation between the two modalities. Our results revealed a high correlation in WBV and BPD between MRI and ABUS. Our study suggests that ABUS provides breast density information useful in the assessment of breast health.


      PubDate: 2016-03-26T04:45:58Z
       
  • Association between Bethesda Categories and Ultrasound Features of
           Conventional Papillary Thyroid Carcinoma
    • Abstract: Publication date: May 2016
      Source:Ultrasound in Medicine & Biology, Volume 42, Issue 5
      Author(s): Ga Ram Kim, Eun-Kyung Kim, Jin Young Kwak, Jung Hyun Yoon, Hee Jung Moon
      The association between categories 3, 5 and 6 of the Bethesda System for Reporting Thyroid Cytopathology and the clinical and ultrasonography (US) features of conventional papillary thyroid carcinoma (PTC) was evaluated. We included 2005 patients diagnosed with conventional PTC at surgery and Bethesda categories 3, 5 and 6 at pre-operative US-guided fine-needle aspiration. Multinomial regression analysis was performed to determine the odds ratio (ORs) of each US feature associated with category 3 or 5, with category 6 as reference. Category 3 and 5 PTCs were smaller (ORs = 0.925 and 0.937) and did not exhibit marked hypo-echogenicity (ORs = 0.341 and 0.268) compared with category 6 PTCs. Category 3 and 5 PTCs exhibited significant macrocalcification (ORs = 2.372 and 1.594) and heterogeneous parenchyma (OR = 1.265 in category 5). In conclusion, conventional PTCs pre-operatively aspirated as Bethesda category 3, 5 or 6 significantly differ in size, macrocalcification, underlying thyroid parenchymal echogenicity and final assessment of US features.


      PubDate: 2016-03-26T04:45:58Z
       
  • Masthead
    • Abstract: Publication date: May 2016
      Source:Ultrasound in Medicine & Biology, Volume 42, Issue 5




      PubDate: 2016-03-26T04:45:58Z
       
  • Editorial Advisory Board
    • Abstract: Publication date: May 2016
      Source:Ultrasound in Medicine & Biology, Volume 42, Issue 5




      PubDate: 2016-03-26T04:45:58Z
       
  • Contents
    • Abstract: Publication date: May 2016
      Source:Ultrasound in Medicine & Biology, Volume 42, Issue 5




      PubDate: 2016-03-26T04:45:58Z
       
  • Feasibility Testing: Three-dimensional Tumor Mapping in Different
           Orientations of Automated Breast Ultrasound
    • Abstract: Publication date: May 2016
      Source:Ultrasound in Medicine & Biology, Volume 42, Issue 5
      Author(s): Chung-Ming Lo, Si-Wa Chan, Ya-Wen Yang, Yeun-Chung Chang, Chiun-Sheng Huang, Yi-Sheng Jou, Ruey-Feng Chang
      A tumor-mapping algorithm was proposed to identify the same regions in different passes of automated breast ultrasound (ABUS). A total of 53 abnormal passes with 41 biopsy-proven tumors and 13 normal passes were collected. After computer-aided tumor detection, a mapping pair was composed of a detected region in one pass and another region in another pass. Location criteria, including the radial position as on a clock, the relative distance and the distance to the nipple, were used to extract mapping pairs with close regions. Quantitative intensity, morphology, texture and location features were then combined in a classifier for further classification. The performance of the classifier achieved a mapping rate of 80.39% (41/51), with an error rate of 5.97% (4/67). The trade-offs between the mapping and error rates were evaluated, and Az = 0.9094 was obtained. The proposed tumor-mapping algorithm was capable of automatically providing location correspondence information that would be helpful in reviews of ABUS examinations.


      PubDate: 2016-03-26T04:45:58Z
       
  • Quantification of Shunt Volume Through Ventricular Septal Defect by
           Real-Time 3-D Color Doppler Echocardiography: An in Vitro Study
    • Abstract: Publication date: May 2016
      Source:Ultrasound in Medicine & Biology, Volume 42, Issue 5
      Author(s): Meihua Zhu, Muhammad Ashraf, Lydia Tam, Cole Streiff, Sumito Kimura, Eriko Shimada, David J. Sahn
      Quantification of shunt volume is important for ventricular septal defects (VSDs). The aim of the in vitro study described here was to test the feasibility of using real-time 3-D color Doppler echocardiography (RT3-D-CDE) to quantify shunt volume through a modeled VSD. Eight porcine heart phantoms with VSDs ranging in diameter from 3 to 25 mm were studied. Each phantom was passively driven at five different stroke volumes from 30 to 70 mL and two stroke rates, 60 and 120 strokes/min. RT3-D-CDE full volumes were obtained at color Doppler volume rates of 15, 20 and 27 volumes/s. Shunt flow derived from RT3-D-CDE was linearly correlated with pump-driven stroke volume (R = 0.982). RT3-D-CDE-derived shunt volumes from three color Doppler flow rate settings and two stroke rate acquisitions did not differ (p > 0.05). The use of RT3-D-CDE to determine shunt volume though VSDs is feasible. Different color volume rates/heart rates under clinically/physiologically relevant range have no effect on VSD 3-D shunt volume determination.


      PubDate: 2016-03-26T04:45:58Z
       
  • Contrast-Enhanced Quantitative Intravascular Elastography: The Impact of
           Microvasculature on Model-Based Elastography
    • Abstract: Publication date: May 2016
      Source:Ultrasound in Medicine & Biology, Volume 42, Issue 5
      Author(s): Steven Huntzicker, Himanshu Shekhar, Marvin M. Doyley
      Model-based intravascular ultrasound elastography visualizes the stress distribution within vascular tissue—information that clinicians could use to predict the propensity of atherosclerotic plaque rupture. However, there are concerns that clusters of microvessels may reduce the accuracy of the estimated stress distribution. Consequently, we have developed a contrast-enhanced intravascular ultrasound system to investigate how plaque microvasculature affects the performance of model-based elastography. In simulations, diameters of 200, 400 and 800 μm were used, where the latter diameter represented a cluster of microvessels. In phantoms, we used a microvessel with a diameter of 750 μm. Peak stress errors of 3% and 38% were incurred in the fibrous cap when stress recovery was performed with and without a priori information about microvessel geometry. The results indicate that incorporating geometric information about plaque microvasculature obtained with contrast-enhanced ultrasound imaging improves the accuracy of estimates of the stress distribution within the fibrous cap precisely.


      PubDate: 2016-03-26T04:45:58Z
       
  • Brain Surface Heating After Exposure to Ultrasound: An Analysis Using
           Thermography
    • Abstract: Publication date: May 2016
      Source:Ultrasound in Medicine & Biology, Volume 42, Issue 5
      Author(s): Michal E. Schneider, Paul Lombardo
      Ultrasound is the imaging modality of choice to monitor brain pathologies in neonates after complicated deliveries. Animal studies have indicated that ultrasound may cause heating of brain tissues. To date, no study has explored brain surface heating by ultrasound during clinically relevant exposure. Hence, we investigated heating effects of B-mode and pulsed Doppler (PD) mode on ex vivo lamb brains using thermography. Five brains were scanned for 5 min in B-mode or for 3 min, 1 min, 30 s or 15 s in PD mode. Brain surface temperature was measured pre- and post-exposure using thermography. The highest mean temperature increase was recorded by B-mode (3.82 ± 0.43°C). All five PD exposure protocols were associated with surface temperature increases of 2.1–2.7°C. These outcomes highlight for the first time that B-mode ultrasound can contribute to brain surface heating during a routine cranial scan. Scan duration should be minimised whenever possible.


      PubDate: 2016-03-26T04:45:58Z
       
  • Acoustic Cluster Therapy: In Vitro and Ex Vivo Measurement of
           Activated Bubble Size Distribution and Temporal Dynamics
    • Abstract: Publication date: May 2016
      Source:Ultrasound in Medicine & Biology, Volume 42, Issue 5
      Author(s): Andrew John Healey, Per Christian Sontum, Svein Kvåle, Morten Eriksen, Ragnar Bendiksen, Audun Tornes, Jonny Østensen
      Acoustic cluster technology (ACT) is a two-component, microparticle formulation platform being developed for ultrasound-mediated drug delivery. Sonazoid microbubbles, which have a negative surface charge, are mixed with micron-sized perfluoromethylcyclopentane droplets stabilized with a positively charged surface membrane to form microbubble/microdroplet clusters. On exposure to ultrasound, the oil undergoes a phase change to the gaseous state, generating 20- to 40-μm ACT bubbles. An acoustic transmission technique is used to measure absorption and velocity dispersion of the ACT bubbles. An inversion technique computes bubble size population with temporal resolution of seconds. Bubble populations are measured both in vitro and in vivo after activation within the cardiac chambers of a dog model, with catheter-based flow through an extracorporeal measurement flow chamber. Volume-weighted mean diameter in arterial blood after activation in the left ventricle was 22 μm, with no bubbles >44 μm in diameter. After intravenous administration, 24.4% of the oil is activated in the cardiac chambers.


      PubDate: 2016-03-26T04:45:58Z
       
  • Comparison of Different Methods of Valsalva Maneuver for Right-to-left
           Shunt Detection by Contrast-Enhanced Transcranial Doppler
    • Abstract: Publication date: May 2016
      Source:Ultrasound in Medicine & Biology, Volume 42, Issue 5
      Author(s): Yu-Zhu Guo, Yong-Sheng Gao, Zhen-Ni Guo, Peng-Peng Niu, Yi Yang, Ying-Qi Xing
      We evaluated 298 patients for right-to-left shunt (RLS) detection by contrast-enhanced transcranial Doppler at rest state (RS), during the conventional Valsalva maneuver (CM), and during the modified Valsalva maneuver (BM: blowing into the connecting tube of a sphygmomanometer at 40 mm Hg for 10 s) in random order, and the degree of RLS along the time of the first microbubble occurrence was recorded. The positive rates were 21.8%, 36.9% and 47.3% for RS, CM and BM, respectively (p < 0.001). BM resulted in a significantly higher positive rate (p = 0.010), and there was a significant difference between the two different methods of VM in terms of the degree of RLS detection (p < 0.001). Further, the first microbubble occurred later during BM than CM (10.22 ± 3.77 s vs. 9.44 ± 4.36 s, p < 0.05). This modified maneuver is an alternative to the conventional one, especially for those who cannot perform the conventional maneuver adequately, but are highly suspected of having RLS.


      PubDate: 2016-03-26T04:45:58Z
       
  • Predictive Value of Conventional Ultrasound and Contrast-Enhanced
           Ultrasound in Early Recurrence of Hepatocellular Carcinoma after Surgical
           Resection
    • Abstract: Publication date: May 2016
      Source:Ultrasound in Medicine & Biology, Volume 42, Issue 5
      Author(s): Yibin Wang, Jintang Liao, Wenjun Qi, Lulu Xie, Yueyi Li
      The goals of the work described here were to study the pre-operative risk factors associated with early recurrence (ER) of hepatocellular carcinoma (HCC) after surgical resection and discuss the value of conventional ultrasound (US) and contrast-enhanced ultrasound (CEUS) in predicting ER of HCC, so as to provide more information for optimizing clinical treatment and improving prognosis. A retrospective analysis was conducted on 59 patients who underwent both US and CEUS examinations pre-operatively and surgical resection for HCC between December 2010 and January 2014 in our hospital. The patients' clinical data, laboratory examination data and ultrasonic imaging diagnostic data were collected. Univariate analysis and logistic regression analysis were performed to determine the independent risk factors for ER of HCC after surgical resection. Diagnostic values of independent risk factors in predicting ER were further evaluated. The 59 patients were divided into the ER group (27 cases) and ER-free group (32 cases). There were no significant differences in age and sex between the two groups (p > 0.05). Univariate analysis revealed that differences in pre-operative serum α-fetoprotein level ≥400 ng/mL (p = 0.008), tumor diameter ≥5 cm (p = 0.012), macroscopic vascular invasion (p = 0.040), “fast wash-out” enhancement pattern (p = 0.006) and inhomogeneous distribution of contrast agent (p = 0.031) statistically significantly differed between the two groups. Logistic regression analysis indicated that pre-operative serum AFP level ≥400 ng/mL (p = 0.024), tumor diameter ≥5 cm (p = 0.042) and “fast wash-out” enhancement pattern (p = 0.009) were independent risk factors for ER of HCC; macrovascular invasion (p = 0.095) and inhomogeneous distribution of contrast agent (p = 0.628) did not statistically significantly differ between two groups (p = 0.628). Predictive values of the independent risk factors were further evaluated. The sensitivity of a “fast wash-out” enhancement pattern in predicting ER of HCC post-operatively did not statistically differ from that of tumor diameter ≥5 cm (p > 0.05), whereas it was significantly higher than the sensitivities of the other predictive indexes (p < 0.05). A pre-operative serum α-fetoprotein level ≥400 ng/mL, tumor diameter ≥5 cm and “fast wash-out” enhancement pattern are independent risk factors for ER of HCC after surgical resection. In addition, the “fast wash-out” enhancement pattern could probably be used to screen populations at high risk of recurrence owing to its high sensitivity in predicting ER of HCC post-operatively. All these findings provide beneficial information for management of HCC.


      PubDate: 2016-03-26T04:45:58Z
       
  • Comparison of Different Pulse Waveforms for Local Pulse Wave Velocity
           Measurement in Healthy and Hypertensive Common Carotid Arteries
           in Vivo
    • Abstract: Publication date: May 2016
      Source:Ultrasound in Medicine & Biology, Volume 42, Issue 5
      Author(s): Chengwu Huang, Yuan Su, Hong Zhang, Lin-Xue Qian, Jianwen Luo
      Pulse wave velocity (PWV), a measurement of arterial stiffness, can be estimated locally by determining the time delay of the pulse waveforms for a known distance as measured in an ultrasound image. Our aim was to compare three ultrasound-based methods for estimation of local PWV based on the measurement of diameter distension waveforms, displacement waveforms of the anterior wall and displacement waveforms of the posterior wall, respectively, in human common carotid arteries in vivo. The local PWVs at both systolic foot (PWVsf) and dicrotic notch (PWVdn) were estimated from ultrasound radiofrequency data of 25 healthy and 24 hypertensive patients for each method. PWV estimation using the distension waveform method was found to have the highest precision in both groups. Both PWVsf and PWVdn were significantly higher in the hypertensive group compared with the healthy group using the distension waveform method (PWVsf: 6.08 ± 1.70 m/s vs. 4.75 ± 0.92 m/s, p = 0.000014; PWVdn: 7.83 ± 2.26 m/s vs. 5.21 ± 0.95 m/s, p < 0.000001), whereas there was no significant difference at a significance level of 0.01 between the two groups when the anterior or posterior wall waveform method was used. Thus, the difference in arterial stiffness between the two groups could be discriminated well by the distension waveform method. The local PWV estimated using distension waveforms might be a promising index for arterial stiffness characterization and hypertension management.


      PubDate: 2016-03-26T04:45:58Z
       
  • Association of Renal Resistive Index with Markers of Extrarenal Vascular
           Changes in Patients with Systemic Lupus Erythematosus
    • Abstract: Publication date: May 2016
      Source:Ultrasound in Medicine & Biology, Volume 42, Issue 5
      Author(s): Massimiliano Morreale, Giuseppe Mulè, Angelo Ferrante, Francesco D'ignoto, Santina Cottone
      Recent data suggest that renal hemodynamic parameters obtained by duplex Doppler sonography, especially the intrarenal resistive index (RRI), may be associated with systemic vascular changes. We evaluated the relationships between RRI and arterial stiffness, assessed by aortic pulse wave velocity, and between RRI and subclinical atherosclerosis, assessed by measuring carotid intima–media thickness in patients with systemic lupus erythematosus. We enrolled 39 patients with systemic lupus erythematosus (mean age 39 y) compared with 19 healthy controls, matched for age and sex. Each participant underwent 24 h of ambulatory blood pressure, aortic pulse wave velocity, carotid intima–media thickness and RRI measurements. RRI correlated significantly with aortic pulse wave velocity (r = 0.44, p = 0.006), and with carotid intima–media thickness (r = 0.46, p = 0.003). Both correlations held (p = 0.01), even after correction for age, mean arterial pressure and glomerular filtration rate. Our results suggest that the RRI may be considered a marker of systemic vascular changes and probably a predictor of cardiovascular risk in patients with systemic lupus erythematosus.


      PubDate: 2016-03-26T04:45:58Z
       
  • Evaluation of Malignancy Grade of Breast Cancer Using
           Perflubutane-Enhanced Ultrasonography
    • Abstract: Publication date: May 2016
      Source:Ultrasound in Medicine & Biology, Volume 42, Issue 5
      Author(s): Norio Masumoto, Takayuki Kadoya, Ai Amioka, Keiko Kajitani, Hideo Shigematsu, Akiko Emi, Kazuo Matsuura, Koji Arihiro, Morihito Okada
      Whether the contrast effects of perflubutane on contrast-enhanced ultrasonography can predict the malignancy grade of breast cancer is unknown. We analyzed associations between perfusion parameters created from time–intensity curves based on enhancement intensity and temporal changes in contrast-enhanced ultrasonography and clinicopathologic factors in 100 consecutive patients with invasive breast cancer. Values of perfusion parameters were significantly greater in estrogen receptor-negative than -positive tumors (peak intensity, p = 0.0002; ascending slope, p = 0.006; area under the curve, p = 0.0006). Variations in the peak intensity of Ki-67 were significantly correlated in all tumors (r = 0.54, p < 0.0001) and in luminal (r = 0.43, p = 0.0002), human epidermal growth factor receptor type 2-positive (r = 0.47, p = 0.047) and triple-negative (r = 0.55, p = 0.043) tumors. Perfusion parameters on contrast-enhanced ultrasonography can provide excellent predictive value for high-grade malignancy and might help to determine appropriate therapeutic strategies.


      PubDate: 2016-03-26T04:45:58Z
       
  • Efficacy of Ablation Therapy for Secondary Hyperparathyroidism by
           Ultrasound Guided Percutaneous Thermoablation
    • Abstract: Publication date: Available online 2 March 2016
      Source:Ultrasound in Medicine & Biology
      Author(s): Junfeng Zhao, Linxue Qian, Yuan Zu, Ying Wei, Xiangdong Hu
      The objective of this study was to explore the value of ultrasound-guided percutaneous microwave thermoablation to treat secondary hyperparathyroidism (SHPT). One hundred and thirty-eight parathyroid glands from 56 patients with SHPT were ablated in this study. All the parathyroid glands were evaluated by real-time contrast-enhanced ultrasound before, during and after ablation. Changes in serum parathyroid hormone (sPTH) levels were measured before treatment and at 1 h, 1 wk, 1 mo and 6 mo after thermoablation treatment. All 56 cases had a 1-mo follow-up, and 34 cases had a 6-mo follow-up. The sPTH level of the 54 cases 1 mo after ablation was significantly lower than that before (p < 0.05). In the 34 cases that had a 6-mo follow-up, the sPTH levels were also significantly lower at 6 mo after ablation than before (p < 0.05). Bone pain in patients improved post-operatively (p < 0.05), but itchiness and insomnia did not improve (p > 0.05). Ultrasound-guided percutaneous microwave thermoablation is a feasible and effective non-surgical alternative treatment for SHPT patients.


      PubDate: 2016-03-04T04:31:36Z
       
  • Improved Estimation of Ultrasound Thermal Strain Using Pulse Inversion
           Harmonic Imaging
    • Abstract: Publication date: Available online 2 March 2016
      Source:Ultrasound in Medicine & Biology
      Author(s): Xuan Ding, Man M. Nguyen, Isaac B. James, Kacey G. Marra, J. Peter Rubin, Steven A. Leers, Kang Kim
      Thermal (temporal) strain imaging (TSI) is being developed to detect the lipid-rich core of atherosclerotic plaques and presence of fatty liver disease. However, the effects of ultrasonic clutter on TSI have not been considered. In this study, we evaluated whether pulse inversion harmonic imaging (PIHI) could be used to improve estimates of thermal (temporal) strain. Using mixed castor oil–gelatin phantoms of different concentrations and artificially introduced clutter, we found that PIHI improved the signal-to-noise ratio of TSI by an average of 213% or 52.1% relative to 3.3- and 6.6-MHz imaging, respectively. In a phantom constructed using human liposuction fat in the presence of clutter, the contrast-to-noise ratio was degraded by 35.1% for PIHI compared with 62.4% and 43.7% for 3.3- and 6.6-MHz imaging, respectively. These findings were further validated using an ex vivo carotid endarterectomy sample. PIHI can be used to improve estimates of thermal (temporal) strain in the presence of clutter.


      PubDate: 2016-03-04T04:31:36Z
       
  • Echogenicity of the Common Carotid Artery Intima–Media Complex in
           Stroke
    • Abstract: Publication date: Available online 2 March 2016
      Source:Ultrasound in Medicine & Biology
      Author(s): Kunihiko Aizawa, Salim Elyas, Damilola D. Adingupu, Francesco Casanova, Kim M. Gooding, Angela C. Shore, W. David Strain, Phillip E. Gates
      The grey-scale median of the common carotid artery intima–media complex (IM-GSM) characterizes arterial wall composition, and a low IM-GSM is associated with increased cardiovascular mortality in the elderly. We aimed to determine differences in the IM-GSM between a cohort with cerebrovascular disease and a healthy cohort. Eighty-two healthy individuals (control group: 63.2 ± 8.7 y) and 96 patients with either stroke or transient ischemic attacks (CRVD group: 68.6 ± 9.8 y) were studied. Common carotid artery intima–media thickness and IM-GSM obtained by ultrasound were analyzed using semi-automated edge-detection software. The IM-GSM was significantly lower in the CRVD group than in the control group (106 ± 24 vs. 124 ± 27 au, p < 0.001). The IM-GSM was similar for the infarct and non-infarct sides in CRVD. In the pooled cohort of all participants, the lower the quartile of IM-GSM, the greater were the carotid artery intima–media thickness and carotid artery remodeling. These results suggest the presence of an altered atherosclerotic phenotype in the intima–media complex of CRVD patients that can be detected by ultrasound.


      PubDate: 2016-03-04T04:31:36Z
       
  • Masthead
    • Abstract: Publication date: April 2016
      Source:Ultrasound in Medicine & Biology, Volume 42, Issue 4




      PubDate: 2016-02-28T03:59:31Z
       
  • Contrast-Enhanced Ultrasonography of Pancreatic Carcinoma: Correlation
           with Pathologic Findings
    • Abstract: Publication date: April 2016
      Source:Ultrasound in Medicine & Biology, Volume 42, Issue 4
      Author(s): Yanjie Wang, Kun Yan, Zhihui Fan, Li Sun, Wei Wu, Wei Yang
      We concluded that contrast-enhanced ultrasound (CEUS) has clinical value in identifying the pathologic changes of pancreatic carcinomas. Forty-three patients diagnosed with pancreatic carcinoma through surgery were retrospectively investigated. CEUS examinations were performed on all patients before surgery. Enhancement patterns on CEUS were observed. Time–intensity curves of CEUS were generated for the regions of interest in the pancreas, and quantitative parameters were obtained. Resected cancer specimens were stained with hematoxylin and eosin for histologic analysis, and the microvascular density (MVD) of the specimens was determined by CD34 immunohistochemical staining. Enhancement patterns of CEUS were compared with histopathologic findings in pancreatic carcinomas. Correlations between time–intensity curve parameters and microvascular density were analyzed. Twenty cases manifested centripetal enhancement, and 23 cases, global enhancement. The amount of tumor necrosis or mucus in the centripetally enhanced pancreatic carcinomas was greater than that in the globally enhanced pancreatic carcinomas (p = 0.027). Thirty-eight of 43 (88.4%) pancreatic carcinomas manifested hypo-enhancement with a maximum intensity (IMAX) <90%. Contrast arrival time in pancreatic carcinoma was longer than that in adjacent pancreatic tissue (p < 0.05). IMAX was positively correlated with microvascular density (r = 0.577, p < 0.05). We concluded that CEUS manifestations could reflect the histologic changes of pancreatic carcinomas and CEUS can be used to evaluate blood perfusion of tumors, as IMAX is positively correlated with microvascular density.


      PubDate: 2016-02-28T03:59:31Z
       
  • Longitudinal Transient Elastography Measurements Used in Follow-up
           for Patients with Cystic Fibrosis
    • Abstract: Publication date: April 2016
      Source:Ultrasound in Medicine & Biology, Volume 42, Issue 4
      Author(s): Stephanie Van Biervliet, Hugo Verdievel, Saskia Vande Velde, Ruth De Bruyne, Danny De Looze, Xavier Verhelst, Anja Geerts, Eddy Robberecht, Hans Van Vlierberghe
      Cystic fibrosis–related liver disease (CFLD) is diagnosed using a combination of criteria. Transient elastography (TE), an ultrasonographic method to evaluate liver stiffness, can differentiate patients with and without liver disease. This retrospective study (2007–2013) aimed to detect developing CFLD using consequent TE measurements. All cystic fibrosis patients with TE measurements between 2007 and 2013 (n = 150, median age 17 (9–24) y) were included, of which 118 had a median of three (range, 2–4) measurements with an interval of 1 (1–2) y. Twenty (14%) had CFLD at the first TE measurement; five (3%) developed CFLD during follow-up. The median TE value in CFLD was 14 kPa (8.7–32.2) compared with 5.3 (4.9–5.7) in cystic fibrosis patients without liver disease (CFnoLD; p = 0.0001). In CFnoLD, TE was correlated with age (p = 0.031). A TE result >6.8 kPa had a sensitivity of 91.5% and a specificity of 91.7% in predicting CFLD, according to the receiver operating characteristics analysis. It also has a positive predictive value of 88.6% and a negative predictive value of 86.9%, increasing to 91.7% and 98%, respectively, in patients at risk (<14 y) for developing CFLD. Patients with developing CFLD had progressively increasing consecutive TE measurements.


      PubDate: 2016-02-28T03:59:31Z
       
  • Editorial Advisory Board
    • Abstract: Publication date: April 2016
      Source:Ultrasound in Medicine & Biology, Volume 42, Issue 4




      PubDate: 2016-02-28T03:59:31Z
       
  • Contents
    • Abstract: Publication date: April 2016
      Source:Ultrasound in Medicine & Biology, Volume 42, Issue 4




      PubDate: 2016-02-28T03:59:31Z
       
  • Breast Lesions: Quantitative Diagnosis Using Ultrasound Shear Wave
           Elastography—A Systematic Review and Meta-Analysis
    • Abstract: Publication date: April 2016
      Source:Ultrasound in Medicine & Biology, Volume 42, Issue 4
      Author(s): Baoxian Liu, Yanling Zheng, Guangliang Huang, Manxia Lin, Quanyuan Shan, Ying Lu, Wenshuo Tian, Xiaoyan Xie
      The aim of this meta-analysis was to estimate the diagnostic performance of shear wave elastography (SWE) in differentiating malignant from benign breast lesions. A literature search of PubMed, Web of Science and Scopus up to November 2014 was conducted. A summary receiver operating characteristic curve was constructed, and pooled weighted estimates of sensitivity and specificity were calculated using a bivariate mixed-effects regression model. Thirty-three studies, which included a total of 5838 lesions (2093 malignant, 3745 benign) from 5397 patients, were finally analyzed. Summary sensitivity and specificity were 0.886 (95% confidence interval [CI], 0.858–0.909) and 0.866 (95% CI, 0.833–0.894), respectively. The pooled diagnostic odds ratio was 50.410 (95% CI, 34.972–72.664). And the area under the receiver operating characteristic curve of SWE was 0.94 (95% CI, 0.91–0.96). No publication bias existed among these studies (p = 0.245). In the subgroup analysis, sensitivity and specificity were 0.862 (95% CI, 0.811–0.901) and 0.875 (95% CI, 0.793–0.928) among 1552 lesions from 1429 patients in the 12 studies using acoustic radiation force impulse imaging and 0.897 (95% CI, 0.863–0.923) and 0.863 (95% CI, 0.831–0.889) among another 4436 lesions from 4097 patients in the 21 studies using supersonic shear imaging. When analysis confined to 9 studies evaluated the diagnostic performance of combination SWE and conventional ultrasound, the area under the curve was 0.96 (95% CI, 0.94–0.97), yielding a sensitivity of 0.971 (95% CI, 0.941–0.986) and specificity of 0.801 (95% CI, 0.733–0.856). SWE seems to be a good quantitative method for differentiating breast lesions, with promise for integration into routine imaging protocols.


      PubDate: 2016-02-28T03:59:31Z
       
  • Ultrasonographic Assessment of Fifth Metatarsophalangeal Joint Erosion in
           Rheumatoid Arthritis: Which Aspect Is Better'
    • Abstract: Publication date: April 2016
      Source:Ultrasound in Medicine & Biology, Volume 42, Issue 4
      Author(s): Nevsun Inanc, Gulsen Ozen, Sibel Zehra Aydin, Esen Kasapoglu-Gunal, Haner Direskeneli
      In this study, the best ultrasound (US) aspect for detection of fifth metatarsophalangeal (MTP) joint erosions, the most frequently eroded joint, in rheumatoid arthritis (RA) patients is investigated. Forty-eight RA patients (F/M = 35/13, mean age and disease durations 50.3 ± 11.8 and 7.9 ± 6.9 y, respectively) were evaluated by B-mode US for erosion. Images were obtained from the dorsal, lateral and plantar aspect of the fifth MTP joint, in longitudinal and transverse scans. The fifth MTP erosions were detected in 36 of 48 patients (75%) and 67 of 96 feet (69.8%). Of the erosions, 15 (22.4%), 53 (79.1%) and 59 (88.0%) were observed at dorsal, lateral and plantar aspects, respectively. Despite not being statistically different, the detection rate of fifth MTP erosions was numerically higher in the plantar aspect than both the lateral and dorsal aspects. In conclusion, the fifth MTP erosions in RA patients are more commonly detected in the plantar aspect US than in dorsal and lateral assessments.


      PubDate: 2016-02-28T03:59:31Z
       
  • In-vivo Axial-strain Sonoelastography Helps Distinguish Acutely-inflamed
           from Fibrotic Terminal Ileum Strictures in Patients with Crohn's
           Disease: Preliminary Results
    • Abstract: Publication date: April 2016
      Source:Ultrasound in Medicine & Biology, Volume 42, Issue 4
      Author(s): Luca Maria Sconfienza, Flaminia Cavallaro, Valentino Colombi, Luca Pastorelli, Gianeugenio Tontini, Lorenzo Pescatori, Anastassia Esseridou, Edoardo Savarino, Carmelo Messina, Roberto Casale, Giovanni Di Leo, Francesco Sardanelli, Maurizio Vecchi
      We tested real-time sonoelastography (RTS) in-vivo to differentiate fibrotic from inflammatory terminal ileum strictures in patients with Crohn's disease (CD), using magnetic resonance enterography (MRE) as a reference standard. Sixteen patients (13 male, 3 female; median [interquartile interval] age = 41 [31–48.5] y; median C-reactive protein (CRP) = 0.95 [0–2.23] mg/dL; median disease duration = 108.5 [35–213.75] mo; median Harvey-Bradshaw Index (HBI) = 3 [3–5.25]) with terminal ileum CD were prospectively included. Short-axis scans were performed; each cross-section was ideally sub-divided into eight circular sectors. Color map provided by RTS was translated into semi-quantitative scale (1 = red; 2 = green; 3 = blue). At MRE, inflammation was seen in nine patients and fibrosis in seven. Total median RTS score was significantly lower in patients with inflammatory stricture (16 [16–18]) than in patients with fibrosis (20 [17.5–22]; p = 0.003). The same happened when the four most superficial quadrants of the loop were considered (8 [7–9] vs. 10 [9–11.5]; p = 0.003). No significant correlation was seen between RTS and HBI (r = 0.467; p = 0.686), RTS and CRP (r = −0.750; p = 0.567) or RTS and disease duration (r = 0.238; p = 0.483). RTS of the terminal ileum in patients with CD is feasible in-vivo, potentially differentiating between fibrotic and inflammatory strictures.


      PubDate: 2016-02-28T03:59:31Z
       
  • Clinical Evaluation of a 3-D Automatic Annotation Method for Breast
           Ultrasound Imaging
    • Abstract: Publication date: April 2016
      Source:Ultrasound in Medicine & Biology, Volume 42, Issue 4
      Author(s): Wei-Wei Jiang, Cheng Li, An-Hua Li, Yong-Ping Zheng
      The routine clinical breast ultrasound annotation method is limited by the time it consumes, inconsistency, inaccuracy and incomplete notation. A novel 3-D automatic annotation method for breast ultrasound imaging has been developed that uses a spatial sensor to track and record conventional B-mode scanning so as to provide more objective annotation. The aim of the study described here was to test the feasibility of the automatic annotation method in clinical breast ultrasound scanning. An ultrasound scanning procedure using the new method was established. The new method and the conventional manual annotation method were compared in 46 breast cancer patients (49 ± 12 y). The time used for scanning a patient was recorded and compared for the two methods. Intra-observer and inter-observer experiments were performed, and intra-class correlation coefficients (ICCs) were calculated to analyze system reproducibility. The results revealed that the new annotation method had an average scanning time 36 s (42.9%) less than that of the conventional method. There were high correlations between the results of the two annotation methods (r = 0.933, p < 0.0001 for distance; r = 0.995, p < 0.0001 for radial angle). Intra-observer and inter-observer reproducibility was excellent, with all ICCs > 0.92. The results indicated that the 3-D automatic annotation method is reliable for clinical breast ultrasound scanning and can greatly reduce scanning time. Although large-scale clinical studies are still needed, this work verified that the new annotation method has potential to be a valuable tool in breast ultrasound examination.


      PubDate: 2016-02-28T03:59:31Z
       
  • Differences in Multi-Modal Ultrasound Imaging between Triple Negative and
           Non-Triple Negative Breast Cancer
    • Abstract: Publication date: April 2016
      Source:Ultrasound in Medicine & Biology, Volume 42, Issue 4
      Author(s): Ziyao Li, Jiawei Tian, Xiaowei Wang, Ying Wang, Zhenzhen Wang, Lei Zhang, Hui Jing, Tong Wu
      The objective of this study was to identify multi-modal ultrasound imaging parameters that could potentially help to differentiate between triple negative breast cancer (TNBC) and non-TNBC. Conventional ultrasonography, ultrasound strain elastography and 3-D ultrasound (3-D-US) findings from 50 TNBC and 179 non-TNBC patients were retrospectively reviewed. Immunohistochemical examination was used as the reference gold standard for cancer subtyping. Different ultrasound modalities were initially analyzed to define TNBC-related features. Subsequently, logistic regression analysis was applied to TNBC-related features to establish models for predicting TNBC. TNBCs often presented as micro-lobulated, markedly hypo-echoic masses with an abrupt interface (p = 0.015, 0.0015 and 0.004, compared with non-TNBCs, respectively) on conventional ultrasound, and showed a diminished retraction pattern phenomenon in the coronal plane (p = 0.035) on 3-D-US. Our findings suggest that B-mode ultrasound and 3-D-US in multi-modality ultrasonography could be a useful non-invasive technique for differentiating TNBCs from non-TNBCs.


      PubDate: 2016-02-28T03:59:31Z
       
  • Magnetic Resonance-Guided High-Intensity Focused Ultrasound Ablation of
           Osteoid Osteoma: A Case Series Report
    • Abstract: Publication date: April 2016
      Source:Ultrasound in Medicine & Biology, Volume 42, Issue 4
      Author(s): Marcello S. Rovella, Guilherme L.P. Martins, Conrado F.A. Cavalcanti, Edson Bor-Seng-Shu, Olavo P. Camargo, Giovanni G. Cerri, Marcos R. Menezes
      Osteoid osteoma is painful benign tumor. The aim of this study was to report our initial experience using magnetic resonance-guided focused ultrasound to treat osteoid osteomas. This retrospective single-center study included four patients treated with magnetic resonance-guided focused ultrasound. They presented with severe pain with reduced quality of life and a poor response to clinical treatment. The pre- and post-treatment evaluation comprised computed tomography and magnetic resonance imaging and focused on quality of life and the impact of pain on daily activities. After treatment, three patients had complete pain resolution with no recurrence. One patient had a recurrence of symptoms after 2 wk and underwent a new successful treatment with increased energy levels. On average, 13 sonications were administered (8–18 sonications/treatment) with an average energy of 2,003 J (range: 1,063–3,522 J). Magnetic resonance-guided focused ultrasound appears to be a feasible, tolerable and effective treatment in selected patients with osteoid osteomas.


      PubDate: 2016-02-28T03:59:31Z
       
  • Supersonic Shear Wave Elastography of Response to Anti-cancer Therapy in a
           Xenograft Tumor Model
    • Abstract: Publication date: April 2016
      Source:Ultrasound in Medicine & Biology, Volume 42, Issue 4
      Author(s): Foucauld Chamming's, Marie-Aude Le-Frère-Belda, Heldmuth Latorre-Ossa, Victor Fitoussi, Alban Redheuil, Franck Assayag, Laetitia Pidial, Jean-Luc Gennisson, Mickael Tanter, Charles-André Cuénod, Laure S. Fournier
      Our objective was to determine if supersonic shear wave elastography (SSWE) can detect changes in stiffness of a breast cancer model under therapy. A human invasive carcinoma was implanted in 22 mice. Eleven were treated with an anti-angiogenic therapy and 11 with glucose for 24 d. Tumor volume and stiffness were assessed during 2 wk before treatment and 0, 7, 12, 20 and 24 d after the start of therapy using SSWE. Pathology was assessed after 12 and 24 d of treatment. We found that response to therapy was associated with early softening of treated tumors only, resulting in a significant difference from non-treated tumors after 12 d of treatment (p = 0.03). On pathology, large areas of necrosis were observed at 12 d in treated tumors. Although treatment was still effective, treated tumors subsequently stiffened during a second phase of the treatment (days 12–24), with a small amount of necrosis observed on pathology on day 24. In conclusion, SSWE was able to measure changes in the stiffness of tumors in response to anti-cancer treatment. However, stiffness changes associated with good response to treatment may change over time, and increased stiffness may also reflect therapy efficacy.


      PubDate: 2016-02-28T03:59:31Z
       
  • Classification of Symptomatic and Asymptomatic Patients with and without
           Cognitive Decline Using Non-invasive Carotid Plaque Strain Indices as
           Biomarkers
    • Abstract: Publication date: April 2016
      Source:Ultrasound in Medicine & Biology, Volume 42, Issue 4
      Author(s): Xiao Wang, Daren C. Jackson, Carol C. Mitchell, Tomy Varghese, Stephanie M. Wilbrand, Brandon G. Rocque, Bruce P. Hermann, Robert J. Dempsey
      Vascular cognitive decline may be caused by micro-emboli generated by carotid plaque instability. We previously found that maximum strain indices in carotid plaque were significantly correlated with cognitive function. In the work described here, we examined these associations with a larger sample size, as well as evaluated the performance of these maximum strain indices in predicting cognitive impairment. Ultrasound-based strain imaging and cognition assessment were conducted on 75 human patients. Patients underwent one of two standardized cognitive test batteries, either the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS) or the National Institute of Neurologic Disorder and Stroke–Canadian Stroke Network (NINDS-CSN) Vascular Cognitive Impairment Harmonization Standards (60 min). Scores were standardized within each battery to allow these data to be combined across all participants. Radiofrequency signals for ultrasound strain imaging were acquired on the carotid arteries using either a Siemens Antares with a VFX 13-5 linear array transducer or a Siemens S2000 with an 18 L6 linear array transducer. The same hierarchical block-matching motion tracking algorithm developed in our laboratory was used to estimate accumulated axial, lateral, and shear strain indices in carotid plaque, with inclusion of adventitia regardless of the ultrasound system and transducer used. Associations between cognitive z-scores and maximum strain indices were examined using Pearson's correlation coefficients. Maximum strain indices were also employed to predict cognitive impairment using receiver operating characteristic analysis. All correlations between maximum strain indices and total cognition were statistically significant (p < 0.05), indicating that these indices have good utility in predicting cognitive impairment. Maximum lateral strain indices provided an area under the curve of 0.85 for symptomatic patients and 0.68 for asymptomatic patients. Our results indicate the important relationship of maximum strain indices to cognitive function and the feasibility of using maximum strain indices to predict cognitive decline with inclusion of the adventitia layer into the segmentation of plaque.


      PubDate: 2016-02-28T03:59:31Z
       
  • Analysis of Systolic Backflow and Secondary Helical Blood Flow in the
           Ascending Aorta Using Vector Flow Imaging
    • Abstract: Publication date: April 2016
      Source:Ultrasound in Medicine & Biology, Volume 42, Issue 4
      Author(s): Kristoffer Lindskov Hansen, Hasse Møller-Sørensen, Jesper Kjaergaard, Maiken Brit Jensen, Jens Teglgaard Lund, Mads Møller Pedersen, Theis Lange, Jørgen Arendt Jensen, Michael Bachmann Nielsen
      Secondary rotational flow and systolic backflow are seen in the ascending aorta and, in this study, were analyzed with the vector velocity method transverse oscillation. Twenty-five patients were scanned intra-operatively, and the vector velocities were related to estimates of transesophageal echocardiography and pulmonary artery catheter thermodilution, and associated with gender, age, aortic diameter, atherosclerotic plaques, left ventricular ejection fraction and previous myocardial infarctions. Secondary flow was present for all patients. The duration and rotational frequency (p < 0.001) and the duration and flow direction of the secondary flow (p < 0.002) were associated. Systolic backflow was present in 40% of the patients and associated with systolic velocities (p < 0.002) and the presence of atherosclerotic plaques (p < 0.001). No other significant associations were observed. The study indicates that backflow is injurious and that secondary flow is a normal flow phenomenon. The study also shows that transverse oscillation can provide new information on blood flow in the ascending aorta.


      PubDate: 2016-02-28T03:59:31Z
       
 
 
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