for Journals by Title or ISSN
for Articles by Keywords
  Subjects -> PHYSICS (Total: 802 journals)
    - MECHANICS (21 journals)
    - NUCLEAR PHYSICS (49 journals)
    - OPTICS (85 journals)
    - PHYSICS (582 journals)
    - SOUND (24 journals)
    - THERMODYNAMICS (32 journals)

PHYSICS (582 journals)

The end of the list has been reached or no journals were found for your choice.
Journal Cover Ultrasound in Medicine & Biology
  [SJR: 0.885]   [H-I: 106]   [8 followers]  Follow
   Full-text available via subscription Subscription journal  (Not entitled to full-text)
   ISSN (Print) 0301-5629
   Published by Elsevier Homepage  [3041 journals]
  • Role of Bowel Ultrasound in the Diagnosis and Follow-up of Patients with
           Crohn's Disease
    • Authors: Clara Benedetta Conti; Mariangela Giunta; Daniele Gridavilla; Dario Conte; Mirella Fraquelli
      Pages: 725 - 734
      Abstract: Publication date: Available online 6 February 2017
      Source:Ultrasound in Medicine & Biology
      Author(s): Clara Benedetta Conti, Mariangela Giunta, Daniele Gridavilla, Dario Conte, Mirella Fraquelli
      Crohn's disease (CD) is an inflammatory chronic bowel disorder; it can involve the whole gastrointestinal tract, but its localization in the ileum or colon is most common. The reference standard for the diagnosis of CD is ileocolonoscopy with histologic assessment. The reference standard for the detection of any complications is surgery. However, imaging techniques have an important role both in the detection/localization of CD and in the follow-up of CD patients. In the last few years, the technical development of ultrasound equipment, the advent of new technologies such as elastography and mostly the increased expertise of sonographers have boosted the role of bowel ultrasound in assessment of the gastrointestinal tract. In fact, bowel ultrasound is particularly attractive thanks to its widespread availability, non-invasiveness, low cost and good reproducibility, as it can be easily repeated during follow-up. The aim of this article is to provide an extensive overview of the actual role of bowel ultrasound in the detection and follow-up of patients with CD.

      PubDate: 2017-03-09T16:22:24Z
      DOI: 10.1016/j.ultrasmedbio.2016.12.014
      Issue No: Vol. 43, No. 4 (2017)
  • 2-D and 3-D Ultrasound for Tumor Volume Analysis:
           A Prospective Study
    • Authors: Segundo J. González; Blaise Mooney; Hui-Yi Lin; Xiuhua Zhao; John V. Kiluk; Nazanin Khakpour; Christine Laronga; M. Catherine Lee
      Pages: 775 - 781
      Abstract: Publication date: Available online 7 February 2017
      Source:Ultrasound in Medicine & Biology
      Author(s): Segundo J. González, Blaise Mooney, Hui-Yi Lin, Xiuhua Zhao, John V. Kiluk, Nazanin Khakpour, Christine Laronga, M. Catherine Lee
      Ultrasound (US) allows real-time tumor assessment. We evaluated the volumetric limits of 2-D and 3-D US, compared with magnetic resonance imaging (MRI), with a prospective institutional review board–approved clinical evaluation of US-to-MRI volumetric correlation. US images of pre- and post-neoadjuvant breast cancers were obtained. Volume discrepancy was evaluated with the non-parametric Wilcoxon signed-rank test. Expected inter-observer variability <14% was evaluated as relative paired difference (RPD); clinical relevance was gauged with the volumetric standard error of the mean (SEM). For 42 patients, 133 of 170 US examinations were evaluable. For tumors ≤20 cm3, both highly correlated to MRI with RPD within inter-observer variability and Pearson's correlation up to 0.86 (0.80 before and 0.86 after neoadjuvant chemotherapy, respectively). Lesions 20–40 cm3 had US-to-MRI discrepancy within inter-observer variability for 2-D (RPD: 13%), but not 3-D (RPD: 27%) US (SEM: 1.47 cm3 for 2-D, SEM: 2.28 cm3 for 3-D), suggesting clinical utility. Tumors >40 cm3 correlated poorly. Tumor volumes ≤20 cm3 exhibited a good correlation to MRI. Studies of clinical applications are warranted.

      PubDate: 2017-03-09T16:22:24Z
      DOI: 10.1016/j.ultrasmedbio.2016.12.009
      Issue No: Vol. 43, No. 4 (2017)
  • Assessment of Structural Heterogeneity and Viscosity in the Cervix Using
           Shear Wave Elasticity Imaging: Initial Results from a Rhesus Macaque Model
    • Authors: Ivan M. Rosado-Mendez; Mark L. Palmeri; Lindsey C. Drehfal; Quinton W. Guerrero; Heather Simmons; Helen Feltovich; Timothy J. Hall
      Pages: 790 - 803
      Abstract: Publication date: Available online 8 February 2017
      Source:Ultrasound in Medicine & Biology
      Author(s): Ivan M. Rosado-Mendez, Mark L. Palmeri, Lindsey C. Drehfal, Quinton W. Guerrero, Heather Simmons, Helen Feltovich, Timothy J. Hall
      Shear wave elasticity imaging has shown promise in evaluation of the pregnant cervix. Changes in shear wave group velocity have been attributed exclusively to changes in stiffness. This assumes homogeneity within the region of interest and purely elastic tissue behavior. However, the cervix is structurally/microstructurally heterogeneous and viscoelastic. We therefore developed strategies to investigate these complex tissue properties. Shear wave elasticity imaging was performed ex vivo on 14 unripened and 13 misoprostol-ripened cervix specimens from rhesus macaques. After tests of significant and uniform shear wave displacement, as well as reliability of estimates, group velocity decreased significantly from the distal (vaginal) to proximal (uterine) end of unripened, but not ripened, specimens. Viscosity was quantified by the slope of the phase velocity versus frequency. Dispersion was observed in both groups (median: 5.5 m/s/kHz, interquartile range: 1.5–12.0 m/s/kHz), also decreasing toward the proximal cervix. This work suggests that comprehensive assessment of complex tissues such as cervix requires consideration of structural heterogeneity and viscosity.

      PubDate: 2017-03-09T16:22:24Z
      DOI: 10.1016/j.ultrasmedbio.2016.12.006
      Issue No: Vol. 43, No. 4 (2017)
  • Single-Beam Acoustic Trapping of Red Blood Cells and Polystyrene
           Microspheres in Flowing Red Blood Cell Saline and Plasma Suspensions
    • Authors: Hsiao-Chuan Liu; Ying Li; Ruimin Chen; Hayong Jung; K. Kirk Shung
      Pages: 852 - 859
      Abstract: Publication date: Available online 22 February 2017
      Source:Ultrasound in Medicine & Biology
      Author(s): Hsiao-Chuan Liu, Ying Li, Ruimin Chen, Hayong Jung, K. Kirk Shung
      Single-beam acoustic tweezers (SBATs) represent a new technology for particle and cell trapping. The advantages of SBATs are their deep penetration into tissues, reduction of tissue damage and ease of application to in vivo studies. The use of these tools for applications in drug delivery in vivo must meet the following conditions: large penetration depth, strong trapping force and tissue safety. A reasonable penetration depth for SBATs in the development of in vivo applications was established in a previous study conducted in water with zero velocity. However, capturing objects in flowing fluid can provide more meaningful results. In this study, we investigated the capability of SBATs to trap red blood cells (RBCs) and polystyrene microspheres in flowing RBC suspensions. Two different types of RBC suspension were prepared in this work: an RBC phosphate-buffered saline (PBS) suspension and an RBC plasma suspension. The results indicated that SBATs successfully trapped RBCs and polystyrene microspheres in a flowing RBC PBS suspension with an average steady velocity of 1.6 cm/s in a 2-mm-diameter polyimide. Furthermore, SBATs were found able to trap RBCs in a flowing RBC PBS suspension at speeds as high as 7.9 cm/s in a polyimide tube, which is higher than the velocity in capillaries (0.03 cm/s) and approaches the velocity in arterioles and venules. Moreover, the results also indicated that polystyrene microspheres can be trapped in an RBC plasma suspension, where aggregation is observed. This work represents a step forward in using this tool in actual in vivo experimentation.

      PubDate: 2017-03-09T16:22:24Z
      DOI: 10.1016/j.ultrasmedbio.2016.12.005
      Issue No: Vol. 43, No. 4 (2017)
  • Neonatal Cranial Ultrasound: Are Current Safety Guidelines
    • Authors: Assema Lalzad; Flora Wong; Michal Schneider
      Pages: 553 - 560
      Abstract: Publication date: March 2017
      Source:Ultrasound in Medicine & Biology, Volume 43, Issue 3
      Author(s): Assema Lalzad, Flora Wong, Michal Schneider
      Ultrasound can lead to thermal and mechanical effects in interrogated tissues. We reviewed the literature to explore the evidence on ultrasound heating on fetal and neonatal neural tissue. The results of animal studies have suggested that ultrasound exposure of the fetal or neonatal brain may lead to a significant temperature elevation at the bone–brain interface above current recommended safety thresholds. Temperature increases between 4.3 and 5.6°C have been recorded. Such temperature elevations can potentially affect neuronal structure and function and may also affect behavioral and cognitive function, such as memory and learning. However, the majority of these studies were carried out more than 25 y ago using non-diagnostic equipment with power outputs much lower than those of modern machines. New studies to address the safety issues of cranial ultrasound are imperative to provide current clinical guidelines and safety recommendations.

      PubDate: 2017-03-09T16:22:24Z
      DOI: 10.1016/j.ultrasmedbio.2016.11.002
  • Totally Implantable Wireless Ultrasonic Doppler Blood Flowmeters: Toward
           Accurate Miniaturized Chronic Monitors
    • Authors: Michael A. Rothfuss; Jignesh V. Unadkat; Michael L. Gimbel; Marlin H. Mickle; Ervin Sejdić
      Pages: 561 - 578
      Abstract: Publication date: March 2017
      Source:Ultrasound in Medicine & Biology, Volume 43, Issue 3
      Author(s): Michael A. Rothfuss, Jignesh V. Unadkat, Michael L. Gimbel, Marlin H. Mickle, Ervin Sejdić
      Totally implantable wireless ultrasonic blood flowmeters provide direct-access chronic vessel monitoring in hard-to-reach places without using wired bedside monitors or imaging equipment. Although wireless implantable Doppler devices are accurate for most applications, device size and implant lifetime remain vastly underdeveloped. We review past and current approaches to miniaturization and implant lifetime extension for wireless implantable Doppler devices and propose approaches to reduce device size and maximize implant lifetime for the next generation of devices. Additionally, we review current and past approaches to accurate blood flow measurements. This review points toward relying on increased levels of monolithic customization and integration to reduce size. Meanwhile, recommendations to maximize implant lifetime should include alternative sources of power, such as transcutaneous wireless power, that stand to extend lifetime indefinitely. Coupling together the results will pave the way for ultra-miniaturized totally implantable wireless blood flow monitors for truly chronic implantation.

      PubDate: 2017-03-09T16:22:24Z
      DOI: 10.1016/j.ultrasmedbio.2016.11.005
  • In Vivo Validation of Volume Flow Measurements of Pulsatile Flow Using a
           Clinical Ultrasound System and Matrix Array Transducer
    • Authors: John M. Hudson; Ross Williams; Laurent Milot; Qifeng Wei; James Jago; Peter N. Burns
      Pages: 579 - 585
      Abstract: Publication date: March 2017
      Source:Ultrasound in Medicine & Biology, Volume 43, Issue 3
      Author(s): John M. Hudson, Ross Williams, Laurent Milot, Qifeng Wei, James Jago, Peter N. Burns
      The goal of this study was to evaluate the accuracy of a non-invasive C-plane Doppler estimation of pulsatile blood flow in the lower abdominal vessels of a porcine model. Doppler ultrasound measurements from a matrix array transducer system were compared with invasive volume flow measurements made on the same vessels with a surgically implanted ultrasonic transit-time flow probe. For volume flow rates ranging from 60 to 750 mL/min, agreement was very good, with a Pearson correlation coefficient of 0.97 (p < 0.0001) and a mean bias of −4.2%. The combination of 2-D matrix array technology and fast processing gives this Doppler method clinical potential, as many of the user- and system-dependent parameters of previous methods, including explicit vessel angle and diameter measurements, are eliminated.

      PubDate: 2017-03-09T16:22:24Z
      DOI: 10.1016/j.ultrasmedbio.2016.10.008
  • Ultrasound Measurements of Skeletal Muscle Architecture Are Associated
           with Strength and Functional Capacity in Older Adults
    • Authors: Isaac Selva Raj; Stephen R. Bird; Anthony J. Shield
      Pages: 586 - 594
      Abstract: Publication date: March 2017
      Source:Ultrasound in Medicine & Biology, Volume 43, Issue 3
      Author(s): Isaac Selva Raj, Stephen R. Bird, Anthony J. Shield
      The goal of this study was to determine whether ultrasound measures of muscle architecture can be used to infer strength and functional capacity in older adults. Thirty-six healthy older adults (aged 68.2 ± 5.3 y) undertook isokinetic dynamometry for isometric and isokinetic concentric knee extensor strength, the 6-m fast walk, timed up and go, stair climb and descent and vertical jump tests. Longitudinal brightness-mode ultrasound scans (probe frequency, 10 MHz) of the vastus lateralis, vastus intermedius, rectus femoris and gastrocnemius medialis were obtained, and muscle architecture measures (thickness, fascicle pennation angle and fascicle length) were correlated with the aforementioned strength and functional measures. Quadriceps thickness was a significant (p < 0.05) independent predictor of isometric and isokinetic knee extensor strength (R 2 ≥ 0.630). Gastrocnemius medialis thickness was a significant independent predictor of 6-m fast walk test (R 2 = 0.216, p < 0.05), timed up and go test (R 2 = 0.455, p < 0.01), stair climb power (R 2 = 0.591, p < 0.01), stair descent power (R 2 = 0.608, p < 0.01) and vertical jump height (R 2 = 0.579, p < 0.01). Ultrasound is a safe, non-invasive and efficient tool for inferring the strength and functional capacity of older adults.

      PubDate: 2017-03-09T16:22:24Z
      DOI: 10.1016/j.ultrasmedbio.2016.11.013
  • Time-Harmonic Elastography of the Liver is Sensitive to Intrahepatic
           Pressure Gradient and Liver Decompression after Transjugular Intrahepatic
           Portosystemic Shunt (TIPS) Implantation
    • Authors: Heiko Tzschätzsch; Ingolf Sack; Stephan Rodrigo Marticorena Garcia; Selcan Ipek-Ugay; Jürgen Braun; Bernd Hamm; Christian E. Althoff
      Pages: 595 - 600
      Abstract: Publication date: March 2017
      Source:Ultrasound in Medicine & Biology, Volume 43, Issue 3
      Author(s): Heiko Tzschätzsch, Ingolf Sack, Stephan Rodrigo Marticorena Garcia, Selcan Ipek-Ugay, Jürgen Braun, Bernd Hamm, Christian E. Althoff
      We investigated the correlation between hepatic venous pressure gradient (HVPG) and liver shear wave speed (SWS) measured by multi-frequency time-harmonic ultrasound elastography (THE) before and after transjugular intrahepatic portosystemic shunt (TIPS) implantation. Ten patients with ascites, cirrhotic liver disease and portal hypertension were prospectively examined with invasive HVPG measurement and THE before and after TIPS implantation. HVPG and SWS decreased after TIPS placement from 20.4 ± 2.2 mmHg to 9.8 ± 4.1 mmHg (mean ± standard deviation) and from 3.87 ± 0.54 m/s to 3.27 ± 0.44 m/s. Mean reduction HVPG was −10.6 ± 3.7 mmHg, p < 0.001; mean reduction SWS was −0.60 ± 0.29 m/s, p < 0.001. A linear correlation was observed between HVPG and SWS (R = 0.59, p = 0.0061). THE-measured SWS is a first potential direct ultrasound marker for liver decompression following TIPS in ascites-associated cirrhotic liver disease and therefore might be suitable to non-invasively detect portal hypertension.

      PubDate: 2017-03-09T16:22:24Z
      DOI: 10.1016/j.ultrasmedbio.2016.10.007
  • Differential Diagnosis of Breast Category 3 and 4 Nodules Through BI-RADS
           Classification in Conjunction with Shear Wave Elastography
    • Authors: Min Wang; Zhi Yang; Can Liu; Junhong Yan; Wenxiao Zhang; Jian Sun; Guanghe Cui
      Pages: 601 - 606
      Abstract: Publication date: March 2017
      Source:Ultrasound in Medicine & Biology, Volume 43, Issue 3
      Author(s): Min Wang, Zhi Yang, Can Liu, Junhong Yan, Wenxiao Zhang, Jian Sun, Guanghe Cui
      Ultrasound (US) has become one of the important imaging methods for differentiating benign from malignant breast lesions. In 2013, the American College of Radiology published the fifth edition of the Breast Imaging-Reporting and Data System (BI-RADS). BI-RADS is a guide with recommendations for the standardization of breast imaging (US, mammography and magnetic resonance imaging) reports and for the auditing of centers employing such methods. Its objective is to standardize the nomenclature used in the reports. However, current US examinations are neither adequately sensitive nor sufficiently specific enough. The average Young's modulus was measured through shear wave elastography (SWE) to evaluate the diagnostic value of the BI-RADS classification in conjunction with SWE in differentiating BI-RADS 3 and 4 nodules. A total of 100 consecutive women with 126 breast lesions, including 65 benign and 61 malignant lesions, were included. The average Young's modulus of breast nodules and peri-nodule tissue (Emean1 and Emean2) was also determined through SWE. A receiver operating characteristic curve was drawn on the basis of pathologic results. The highest cut-off values were C1 and C2. At Emean1 > C1 or Emean2 > C2, BI-RADS 3 was increased to 4a and BI-RADS 4a was increased to 4b. At Emean1 ≤ C1 and Emean2 ≤ C2, BI-RADS 4b was decreased to 4a. Other BI-RADS classifications remained unchanged. BI-RADS 3 and 4a were considered benign. BI-RADS 4b and 4c were malignant. The area under the curve, sensitivity and specificity of the BI-RADS classification in conjunction with SWE were 0.952, 93.4% and 95.4%, respectively. The area under the curve, sensitivity and specificity of the original BI-RADS classification were 0.883, 82.0% and 87.7%, respectively. Differences were statistically significant (p = 0.028, Z-test). The diagnostic sensitivity and specificity were increased effectively. As a new method, BI-RADS classification in conjunction with SWE that combines the average Young's modulus yields a high value in terms of the differential diagnosis of breast nodules.

      PubDate: 2017-03-09T16:22:24Z
      DOI: 10.1016/j.ultrasmedbio.2016.10.004
  • Quantitative Analysis of Contrast-Enhanced Ultrasound Imaging in Invasive
           Breast Cancer: A Novel Technique to Obtain Histopathologic Information of
           Microvessel Density
    • Authors: Naoko Mori; Shunji Mugikura; Shoki Takahashi; Koichi Ito; Chiaki Takasawa; Li Li; Minoru Miyashita; Atsuko Kasajima; Yu Mori; Takanori Ishida; Tetsuya Kodama; Kei Takase
      Pages: 607 - 614
      Abstract: Publication date: March 2017
      Source:Ultrasound in Medicine & Biology, Volume 43, Issue 3
      Author(s): Naoko Mori, Shunji Mugikura, Shoki Takahashi, Koichi Ito, Chiaki Takasawa, Li Li, Minoru Miyashita, Atsuko Kasajima, Yu Mori, Takanori Ishida, Tetsuya Kodama, Kei Takase
      We examined whether enhancement area ratios obtained by the new bubble detection method correlate with histologic microvessel density in invasive breast cancer. Forty consecutive patients with invasive breast cancer lesions underwent contrast-enhanced ultrasound. The ratio of enhanced area to manually segmented tumor area (enhancement area ratio) was obtained with the new method at peak and delayed phases (50–54, 55–59, 60–64 and 65–69 s). We also analyzed time–intensity curves to obtain peak intensity and area under curve. Enhancement area ratios in both peak and delayed phases (50–54, 55–59, 60–64 and 65–69 s) were significantly correlated with microvessel density (r = 0.57, 0.62, 0.68, 0.61 and 0.58; p = 0.0001, <0.0001, <.0001, <.0001 and 0.0001, respectively). In time–intensity curve analysis, peak intensity was significantly correlated (r = 0.43, p = 0.0073), whereas area under the curve was not (r = 0.29, p = 0.0769). Enhancement area ratios obtained by the new method were correlated with microvessel density in invasive breast cancer.

      PubDate: 2017-03-09T16:22:24Z
      DOI: 10.1016/j.ultrasmedbio.2016.11.009
  • A Novel Approach to Detecting Postpartum Hemorrhage Using
           Contrast-Enhanced Ultrasound
    • Authors: Kenji Imai; Tomomi Kotani; Hiroyuki Tsuda; Tomoko Nakano; Akihiro Hirakawa; Fumitaka Kikkawa
      Pages: 615 - 620
      Abstract: Publication date: March 2017
      Source:Ultrasound in Medicine & Biology, Volume 43, Issue 3
      Author(s): Kenji Imai, Tomomi Kotani, Hiroyuki Tsuda, Tomoko Nakano, Akihiro Hirakawa, Fumitaka Kikkawa
      The aim of this study was to estimate the efficacy of contrast-enhanced ultrasound (CEUS) in detecting postpartum hemorrhage (PPH) after cesarean section. This is the first study of CEUS in obstetric hemorrhage. A total of 37 patients, operated at Nagoya University Hospital, underwent CEUS. We evaluated the findings of CEUS, which were qualitatively defined as positive when pooling or leakage of contrast agent was observed in the uterine cavity, by measuring the amount of bleeding during the first 4 h after cesarean section. The time–intensity curve patterns of leaked contrast agents were also analyzed for quantitative prediction of the amount of blood loss. Significant differences between the excessive hemorrhage (N = 7) and non-excessive hemorrhage groups (N = 30) were noted in the occurrence of positive CEUS (p = 0.011). Additionally, mean postpartum blood loss markedly increased in patients with a positive CEUS (p = 0.002). From a quantitative perspective, the time until leakage of contrast agents was detected correlated with the amount of bleeding, but the other characteristics of the time–intensity curve pattern did not provide valuable information. In conclusion, CEUS, which enables bedside assessment and rapid diagnosis, is a promising strategy for the detection of PPH.

      PubDate: 2017-03-09T16:22:24Z
      DOI: 10.1016/j.ultrasmedbio.2016.11.008
  • Contrast-Enhanced Ultrasound Using Perfluorobutane-Containing Microbubbles
           in the Assessment of Liver Allograft Damage: An Exploratory Prospective
    • Authors: Ijin Joo; Jae Young Lee; Dong Ho Lee; Ju Hyeon Jeon; Hyeyoung Kim; Nam-Joon Yi; Kwang-Woong Lee; Kyung-Suk Suh
      Pages: 621 - 628
      Abstract: Publication date: March 2017
      Source:Ultrasound in Medicine & Biology, Volume 43, Issue 3
      Author(s): Ijin Joo, Jae Young Lee, Dong Ho Lee, Ju Hyeon Jeon, Hyeyoung Kim, Nam-Joon Yi, Kwang-Woong Lee, Kyung-Suk Suh
      This prospective study investigated the usefulness of contrast (perfluorobutane-containing microbubbles)-enhanced ultrasound in the non-invasive assessment of liver allograft damage. Forty-one liver recipients underwent contrast-enhanced ultrasound followed by a liver biopsy. The hepatic filling rate (time between the arrival of contrast agent in the right hepatic artery and the maximum intensity of hepatic parenchyma) and parenchymal intensity difference before and after instantaneous high-power emission in the Kupffer phase were measured. Patients with allograft damage had higher hepatic filling rates and lower parenchymal intensity differences than those without damage (42.0 ± 16.9 vs. 30.5 ± 7.7 s, p = 0.005; 6.1 ± 7.4 vs. 16.6 ± 16.1 dB, p = 0.047, respectively). In the diagnosis of liver allograft damage, hepatic filling rate and parenchymal intensity difference had sensitivities of 61.5% and 90.9% and specificities of 92.6% and 63.6% using cutoffs of >38.5 s and ≤10.3 dB, respectively. In conclusion, contrast-enhanced ultrasound may be a promising tool in the detection of liver allograft damage.

      PubDate: 2017-03-09T16:22:24Z
      DOI: 10.1016/j.ultrasmedbio.2016.11.012
  • Effects of Non-Focused Microbubble-Enhanced and High-Intensity Focused
           Ultrasound on Hemostasis in a Rabbit Model of Liver Trauma
    • Authors: Da-Wei Zhao; Meng Tian; Jian-Zhong Zou; Yuan-Yi Zheng; Tao Li
      Pages: 629 - 639
      Abstract: Publication date: March 2017
      Source:Ultrasound in Medicine & Biology, Volume 43, Issue 3
      Author(s): Da-Wei Zhao, Meng Tian, Jian-Zhong Zou, Yuan-Yi Zheng, Tao Li
      Uncontrolled hemorrhage after trauma to the liver can lead to death. The present study compared the effects of non-focused microbubble-enhanced ultrasound and high-intensity focused ultrasound on hepatic hemostasis in the injured liver. Blood perfusion level, serum liver enzyme levels and the aspartate transaminase/alanine transaminase ratio differed between the two types of treatment (all p values < 0.05). Hepatic cells in the microbubble-enhanced ultrasound group exhibited edema and compressed the hepatic sinus and blood vessels in the portal area. Coagulation and necrosis, inflammatory cell infiltration, and fibrous tissue encapsulation were observed in the high-intensity focused ultrasound group at later stages. The groups also differed in degree of ultrastructural damage and recovery time. Thus, microbubble-enhanced ultrasound has less of an impact on blood reperfusion and surrounding normal tissue than high-intensity focused ultrasound and is a better choice for the treatment of liver trauma.

      PubDate: 2017-03-09T16:22:24Z
      DOI: 10.1016/j.ultrasmedbio.2016.11.014
  • Cesarean Scar Pregnancy: Comparing the Efficacy and Tolerability of
           Treatment with High-Intensity Focused Ultrasound and Uterine Artery
    • Authors: Juhua Xiao; Zhen Shi; Jinshui Zhou; Jun Ye; Jianfang Zhu; Xin Zhou; Fang Wang; Shouhua Zhang
      Pages: 640 - 647
      Abstract: Publication date: March 2017
      Source:Ultrasound in Medicine & Biology, Volume 43, Issue 3
      Author(s): Juhua Xiao, Zhen Shi, Jinshui Zhou, Jun Ye, Jianfang Zhu, Xin Zhou, Fang Wang, Shouhua Zhang
      The aim of this study was to investigate the clinical efficacy of high-intensity focused ultrasound (HIFU) for the treatment of a cesarean scar pregnancy compared with uterine artery embolization (UAE) and intra-arterial methotrexate infusion combined with uterine curettage. In this retrospective cohort study, 31 patients were treated with HIFU (HIFU group), and 45 patients were treated with UAE (UAE group). We compared the treatment and recovery of the patients, including follow-up. After UAE treatment, serum levels of the β subunit of human chorionic gonadotropin declined significantly on the first day, and the residual lesions disappeared in 3–17 wk. One patient underwent hysterectomy; intrauterine adhesions were found by hysteroscopic examination after 6 mo in 2 patients, whose menstrual function did not return to normal. The remainder of the 42 patients recovered normal menstrual functioning during the 3- to 18-wk follow-up. In the patients who underwent HIFU treatment, serum β-HCG levels did not decline rapidly; serum β-HCG levels increased in many patients and then declined to normal steadily within 2–12 wk. Lesions detached in 3–14 wk in all patients, and menstrual functioning was recovered in 3–9 wk without uterine curettage. Compared with the UAE group, the HIFU group had less pain and fewer complications; the patients in the HIFU group were not hospitalized or anesthetized and had lower costs. HIFU is an efficient, tolerable and non-invasive treatment.

      PubDate: 2017-03-09T16:22:24Z
      DOI: 10.1016/j.ultrasmedbio.2016.11.001
  • Strain-Initialized Robust Bone Surface Detection in 3-D Ultrasound
    • Authors: Mohammad Arafat Hussain; Antony J. Hodgson; Rafeef Abugharbieh
      Pages: 648 - 661
      Abstract: Publication date: March 2017
      Source:Ultrasound in Medicine & Biology, Volume 43, Issue 3
      Author(s): Mohammad Arafat Hussain, Antony J. Hodgson, Rafeef Abugharbieh
      Three-dimensional ultrasound has been increasingly considered as a safe radiation-free alternative to radiation-based fluoroscopic imaging for surgical guidance during computer-assisted orthopedic interventions, but because ultrasound images contain significant artifacts, it is challenging to automatically extract bone surfaces from these images. We propose an effective way to extract 3-D bone surfaces using a surface growing approach that is seeded from 2-D bone contours. The initial 2-D bone contours are estimated from a combination of ultrasound strain images and envelope power images. Novel features of the proposed method include: (i) improvement of a previously reported 2-D strain imaging-based bone segmentation method by incorporation of a depth-dependent cumulative power of the envelope into the elastographic data; (ii) incorporation of an echo decorrelation measure-based weight to fuse the strain and envelope maps; (iii) use of local statistics of the bone surface candidate points to detect the presence of any bone discontinuity; and (iv) an extension of our 2-D bone contour into a 3-D bone surface by use of an effective surface growing approach. Our new method produced average improvements in the mean absolute error of 18% and 23%, respectively, on 2-D and 3-D experimental phantom data, compared with those of two state-of-the-art bone segmentation methods. Validation on 2-D and 3-D clinical in vivo data also reveals, respectively, an average improvement in the mean absolute fitting error of 55% and an 18-fold improvement in the computation time.

      PubDate: 2017-03-09T16:22:24Z
      DOI: 10.1016/j.ultrasmedbio.2016.11.003
  • Diagnosis of Complex Pulley Ruptures Using Ultrasound in Cadaver
    • Authors: Isabelle Schöffl; Arnica Hugel; Volker Schöffl; Wolfgang Rascher; Jörg Jüngert
      Pages: 662 - 669
      Abstract: Publication date: March 2017
      Source:Ultrasound in Medicine & Biology, Volume 43, Issue 3
      Author(s): Isabelle Schöffl, Arnica Hugel, Volker Schöffl, Wolfgang Rascher, Jörg Jüngert
      Pulley ruptures are common in climbing athletes. The purposes of this study were to determine the specific positioning of each pulley with regards to the joint, and to evaluate the ultrasound diagnostics of various pulley rupture combinations. For this, 34 cadaver fingers were analyzed via ultrasound, the results of which were compared to anatomic measurements. Different pulley ruptures were then simulated and evaluated using ultrasound in standardized dynamic forced flexion. Visualization of the A2 and A4 pulleys was achieved 100% of the time, while the A3 pulley was visible in 74% of cases. Similarly, injuries to the A2 and A4 pulleys were readily observable, while A3 pulley injuries were more challenging to identify (sensitivity of 0.2 for singular A3 pulley, 0.5 for A2/A4 pulley and 0.33 for A3/A4 pulley ruptures). Receiver operating characteristic analysis was used to evaluate the optimal tendon-bone distance for pulley rupture diagnosis, a threshold which was determined to be 1.9 mm for A2 pulley ruptures and 1.85 for A4 pulley ruptures. This study was the first to carry out a cadaver ultrasound examination of a wide variety of pulley ruptures. Ultrasound is a highly accurate tool for visualizing the A2 and A4 pulleys in a cadaver model. This method of pathology diagnosis was determined to be suitable for injuries to the A2 and A4 pulleys, but inadequate for A3 pulley injuries.

      PubDate: 2017-03-09T16:22:24Z
      DOI: 10.1016/j.ultrasmedbio.2016.10.005
  • High-Resolution Elastography for Thin-Layer Mechanical Characterization:
           Toward Skin Investigation
    • Authors: Caroline Chartier; Yassine Mofid; Cécile Bastard; Véronique Miette; Annabel Maruani; Laurent Machet; Frédéric Ossant
      Pages: 670 - 681
      Abstract: Publication date: March 2017
      Source:Ultrasound in Medicine & Biology, Volume 43, Issue 3
      Author(s): Caroline Chartier, Yassine Mofid, Cécile Bastard, Véronique Miette, Annabel Maruani, Laurent Machet, Frédéric Ossant
      Interest in elasticity estimation for thin layers is increasing because of the various potential applications, including dermatology and cosmetology. In this context, we propose a dedicated elastographic system using 1-D high-frequency transient elastography (HF-TE) to estimate the 1-D Young's modulus through the dermis and hypodermis, which are the two human skin layers of interest in this study. An experimental validation of the HF-TE method was first carried out on two homogeneous tissue-mimicking hard and soft phantoms. The Young's modulus values obtained in these phantoms were compared with those obtained by two complementary shear wave propagation techniques: shear wave-induced resonance elastography (SWIRE) and supersonic shear imaging (SSI). A third two-layer thin phantom, with mechanical properties similar to those of skin, was used to validate the ability of HF-TE to distinguish layers and measure elasticity. Finally, preliminary in vivo experiments conducted on forearm and cheek skin revealed the promising performance of HF-TE in measuring elasticity in the dermis and hypodermis.

      PubDate: 2017-03-09T16:22:24Z
      DOI: 10.1016/j.ultrasmedbio.2016.11.007
  • Principal Strain Vascular Elastography: Simulation and Preliminary
           Clinical Evaluation
    • Authors: Rohit Nayak; Steven Huntzicker; Jacques Ohayon; Nancy Carson; Vikram Dogra; Giovanni Schifitto; Marvin M. Doyley
      Pages: 682 - 699
      Abstract: Publication date: March 2017
      Source:Ultrasound in Medicine & Biology, Volume 43, Issue 3
      Author(s): Rohit Nayak, Steven Huntzicker, Jacques Ohayon, Nancy Carson, Vikram Dogra, Giovanni Schifitto, Marvin M. Doyley
      It is difficult to produce reliable polar strain elastograms (radial and circumferential) because the center of the carotid artery is typically unknown. Principal strain imaging can overcome this limitation, but suboptimal lateral displacement estimates make this an impractical approach for visualizing mechanical properties within the carotid artery. We hypothesized that compounded plane wave imaging can minimize this problem. To test this hypothesis, we performed (i) simulations with vessels of varying morphology and mechanical behavior (i.e., isotropic and transversely isotropic), and (ii) a pilot study with 10 healthy volunteers. The accuracy of principal and polar strain (computed using knowledge of the precise vessel center) elastograms varied between 7% and 17%. In both types of elastograms, strain concentrated at the junction between the fibrous cap and the vessel wall, and the strain magnitude decreased with increasing fibrous cap thickness. Elastograms of healthy volunteers were consistent with those of transversely isotropic homogeneous vessels; they were spatially asymmetric, a trend that was common to both principal and polar strains. No significant differences were observed in the mean strain recovered from principal and polar strains (p > 0.05). This investigation indicates that principal strain elastograms measured with compounding plane wave imaging overcome the problems incurred when polar strain elastograms are computed with imprecise estimates of the vessel center.

      PubDate: 2017-03-09T16:22:24Z
      DOI: 10.1016/j.ultrasmedbio.2016.11.010
  • Acoustic Impedance Analysis with High-Frequency Ultrasound for
           Identification of Fatty Acid Species in the Liver
    • Authors: Kazuyo Ito; Kenji Yoshida; Hitoshi Maruyama; Jonathan Mamou; Tadashi Yamaguchi
      Pages: 700 - 711
      Abstract: Publication date: March 2017
      Source:Ultrasound in Medicine & Biology, Volume 43, Issue 3
      Author(s): Kazuyo Ito, Kenji Yoshida, Hitoshi Maruyama, Jonathan Mamou, Tadashi Yamaguchi
      Acoustic properties of free fatty acids present in the liver were studied as a possible basis for non-invasive ultrasonic diagnosis of non-alcoholic steatohepatitis. Acoustic impedance was measured for the following types of tissue samples: Four pathologic types of mouse liver, five kinds of FFAs in solvent and five kinds of FFAs in cultured Huh-7 cells. A transducer with an 80-MHz center frequency was incorporated into a scanning acoustic microscopy system. Acoustic impedance was calculated from the amplitude of the signal reflected from the specimen surface. The Kruskal–Wallis test revealed statistically significant differences (p < 0.01) in acoustic impedance not only among pathologic types, but also among the FFAs in solvent and in cultured Huh-7 cells. These results suggest that each of the FFAs, especially palmitate, oleate and palmitoleate acid, can be distinguished from each other, regardless of whether they were in solution or absorbed by cells.

      PubDate: 2017-03-09T16:22:24Z
      DOI: 10.1016/j.ultrasmedbio.2016.11.011
  • Whole-Breast Ultrasound for Breast Screening and Archiving
    • Authors: Chiun-Sheng Huang; Ya-Wen Yang; Rong-Tai Chen; Chung-Ming Lo; Chao Lo; Ching-Fen Cheng; Chao-Shuan Lee; Ruey-Feng Chang
      Abstract: Publication date: Available online 7 March 2017
      Source:Ultrasound in Medicine & Biology
      Author(s): Chiun-Sheng Huang, Ya-Wen Yang, Rong-Tai Chen, Chung-Ming Lo, Chao Lo, Ching-Fen Cheng, Chao-Shuan Lee, Ruey-Feng Chang
      The incidence of breast cancer is increasing worldwide, reinforcing the importance of breast screening. Conventional hand-held ultrasound (HHUS) for breast screening is efficient and relatively easy to perform; however, it lacks systematic recording and localization. This study investigated an electromagnetic tracking-based whole-breast ultrasound (WBUS) system to facilitate the use of HHUS for breast screening. One-hundred nine breast masses were collected, and the detection of suspicious breast lesions was compared between the WBUS system, HHUS and a commercial automated breast ultrasound (ABUS) system. The positioning error between WBUS and ABUS (1.39 ± 0.68 cm) was significantly smaller than that between HHUS and ABUS (1.62 ± 0.91 cm, p = 0.014) and HHUS and WBUS (1.63 ± 0.9 cm, p = 0.024). WBUS is a practical clinical tool for breast screening that can be used instead of the often unavailable and costly ABUS.

      PubDate: 2017-03-09T16:22:24Z
      DOI: 10.1016/j.ultrasmedbio.2017.01.009
  • Pharmacokinetics of Perfluorobutane after Intra-venous Bolus Injection of
           Sonazoid in Healthy Chinese Volunteers
    • Authors: Pengfei Li; Susan Hoppmann; Ping Du; Huiling Li; Paul M. Evans; Siver A. Moestue; Weiyue Yu; Fang Dong; Hongchuan Liu; Lihong Liu
      Abstract: Publication date: Available online 7 March 2017
      Source:Ultrasound in Medicine & Biology
      Author(s): Pengfei Li, Susan Hoppmann, Ping Du, Huiling Li, Paul M. Evans, Siver A. Moestue, Weiyue Yu, Fang Dong, Hongchuan Liu, Lihong Liu
      Sonazoid is an ultrasound contrast agent based on microbubbles (MB) containing perfluorobutane (PFB) gas. Sonazoid is approved in Japan, Korea and Norway for contrast-enhanced ultrasonography of focal liver lesions and focal breast lesions (Japan only). The objective of this study was to determine the pharmacokinetics (PKs) and safety of Sonazoid in Chinese healthy volunteers (HVs) and to evaluate the potential for ethnic differences in PKs between Chinese and Caucasian HVs. Sonazoid was administered as an intra-venous bolus injection at the clinical dose of 0.12 μL or 0.60 μL MB/kg body weight to two groups of eight Chinese HVs. Expired air and blood samples were collected and analyzed using a validated gas chromatographic tandem mass spectrometry method, and the main PK parameters were calculated. The highest PFB concentrations in blood were observed shortly after intra-venous administration of Sonazoid, and elimination of PFB was rapid. In the 0.12 μL MB/kg body weight cohort, PFB concentrations above the limit of quantification were observed for only 10 to 15 min post-injection. In the 0.60 μL MB/kg body weight cohort, PFB concentrations above the limit of quantification were observed for 60 min post-injection, and the shape of the elimination curve suggested a biphasic elimination profile. The maximum observed concentration (C max) values of PFB in blood were 2.3 ± 1.1 and 19.1 ± 9.2 ng/g for the 0.12 and 0.60 μL MB/kg body weight dose groups (mean ± standard deviation). Area under the curve values were 10.1 ± 2.7 and 90.1 ± 38.3 ng × min/g for the 0.12 and 0.60 μL MB/kg body weight dose groups. C max values of PFB in exhaled air were 0.35 ± 0.2 and 2.4 ± 0.7 ng/mL for the 0.12 and 0.60 μL MB/kg body weight dose groups. Assessment of laboratory parameters, vital signs, oxygen saturation and electrocardiograms revealed no changes indicative of a concern. The PK profile and safety data generated in the Chinese HVs were comparable to previous data for Caucasian HVs.

      PubDate: 2017-03-09T16:22:24Z
      DOI: 10.1016/j.ultrasmedbio.2017.01.003
  • Effect of Hypoxemia on Fetal Ventricular Deformation in a Chronically
           Instrumented Sheep Model
    • Authors: Amarnath Bhide; Juha Rasanen; Heikki Huhta; Juulia Junno; Tiina Erkinaro; Pasi Ohtonen; Mervi Haapsamo; Ganesh Acharya
      Abstract: Publication date: Available online 6 March 2017
      Source:Ultrasound in Medicine & Biology
      Author(s): Amarnath Bhide, Juha Rasanen, Heikki Huhta, Juulia Junno, Tiina Erkinaro, Pasi Ohtonen, Mervi Haapsamo, Ganesh Acharya
      We hypothesized that in near-term sheep fetuses, hypoxemia changes myocardial function as reflected in altered ventricular deformation on speckle-tracking echocardiography. Fetuses in 21 pregnant sheep were instrumented. After 4 d of recovery, fetal cardiac function was assessed by echocardiography at baseline, after 30 and 120 min of induced fetal hypoxemia and after its reversal. Left (LV) and right (RV) ventricular cardiac output and myocardial strain were measured. Baseline mean (standard deviation [SD]) LV and RV global longitudinal strains were −18.7% (3.8) and −14.3% (5.3). Baseline RV global longitudinal and circumferential deformations were less compared with those of the left ventricle (p = 0.016 and p < 0.005). LV, but not RV, global longitudinal strain was decreased (p = 0.003) compared with baseline with hypoxemia. Circumferential and radial strains did not exhibit significant changes. In the near-term sheep fetus, LV global longitudinal and circumferential strains are more negative than RV strains. Acute hypoxemia leads to LV rather than RV dysfunction as reflected by decreased deformation.

      PubDate: 2017-03-09T16:22:24Z
      DOI: 10.1016/j.ultrasmedbio.2017.01.010
  • Assessment of Curve Flexibility on Scoliotic Surgical Candidates Using
           Ultrasound Imaging Method
    • Authors: Rui Zheng; Doug Hill; Douglas Hedden; Marc Moreau; Lawrence H. Le; Jim Raso; Edmond Lou
      Abstract: Publication date: Available online 6 March 2017
      Source:Ultrasound in Medicine & Biology
      Author(s): Rui Zheng, Doug Hill, Douglas Hedden, Marc Moreau, Lawrence H. Le, Jim Raso, Edmond Lou
      The ultrasound imaging method was implemented to assess the spinal curve flexibility of scoliotic surgical candidates, or how much correction it can achieve while patients are bending or lying down. Fifteen participants were recruited. Pre-operative radiographs and ultrasound images in both standing and bending positions were acquired. The post-operative standing radiographs were obtained 1 wk after surgery. Two raters (RZ, EL) measured the ultrasound images twice, 1 wk apart. A curve correction index (C I ) was developed to estimate the curve flexibility. The C I from the pre-operative bending radiograph, ultrasound and post-operative radiograph were 0.51 ± 0.18; R1: 0.74 ± 0.08 vs R2: 0.72 ± 0.09 and 0.60 ± 0.10, respectively. The correlation of C I between ultrasound and post-operative radiography was slightly higher than the pre-operative bending and post-operative radiography. This pilot study demonstrated the bending ultrasound method is a promising supplemental tool to assess curve flexibility before surgical intervention for scoliotic surgical candidates.

      PubDate: 2017-03-09T16:22:24Z
      DOI: 10.1016/j.ultrasmedbio.2017.01.017
  • Editorial Advisory Board
    • Abstract: Publication date: March 2017
      Source:Ultrasound in Medicine & Biology, Volume 43, Issue 3

      PubDate: 2017-03-09T16:22:24Z
  • Comparison of Two Inexpensive Rapid Prototyping Methods for Manufacturing
           Filament Target Ultrasound Phantoms
    • Abstract: Publication date: March 2017
      Source:Ultrasound in Medicine & Biology, Volume 43, Issue 3
      Author(s): Krisztián Füzesi, Miklós Gyöngy
      Current use of 3-D printers to manufacture ultrasound phantoms is limited to relatively expensive photopolymer jetting printers. The present work investigates the feasibility of using two common and inexpensive 3-D printer technologies, fused deposition modeling (FDM) and digital light processing (DLP), to print custom filament target phantoms. Acoustic characteristics obtained from printed solid blocks indicated that the printing materials—acrylonitrile butadiene styrene and polylactic acid for FDM and a photopolymer for DLP printing—were appropriate for use as scatterers. A regular grid of filaments was printed to study printing accuracy. As a proof of concept of the phantom manufacturing process, a complex pattern of filament targets was placed in de-ionized water to create a phantom, which was then imaged using an ultrasound imager. The pattern was clearly identifiable, although multiple reflections were observed, which underscores the importance of future work to enhance printing resolution. This goal is deemed possible using improvement of the DLP printing setup.

      PubDate: 2017-03-09T16:22:24Z
  • Calendar
    • Abstract: Publication date: March 2017
      Source:Ultrasound in Medicine & Biology, Volume 43, Issue 3

      PubDate: 2017-03-09T16:22:24Z
  • Acoustic Behavior of Halobacterium salinarum Gas Vesicles in the
           High-Frequency Range: Experiments and Modeling
    • Authors: Emmanuel Cherin; Johan M. Melis; Raymond W. Bourdeau; Melissa Yin; Dennis M. Kochmann; F. Stuart Foster; Mikhail G. Shapiro
      Abstract: Publication date: Available online 1 March 2017
      Source:Ultrasound in Medicine & Biology
      Author(s): Emmanuel Cherin, Johan M. Melis, Raymond W. Bourdeau, Melissa Yin, Dennis M. Kochmann, F. Stuart Foster, Mikhail G. Shapiro
      Gas vesicles (GVs) are a new and unique class of biologically derived ultrasound contrast agents with sub-micron size whose acoustic properties have not been fully elucidated. In this study, we investigated the acoustic collapse pressure and behavior of Halobacterium salinarum gas vesicles at transmit center frequencies ranging from 12.5 to 27.5 MHz. The acoustic collapse pressure was found to be above 550 kPa at all frequencies, nine-fold higher than the critical pressure observed under hydrostatic conditions. We illustrate that gas vesicles behave non-linearly when exposed to ultrasound at incident pressure ranging from 160 kPa to the collapse pressure and generate second harmonic amplitudes of −2 to −6 dB below the fundamental in media with viscosities ranging from 0.89 to 8 mPa·s. Simulations performed using a Rayleigh–Plesset-type model accounting for buckling and a dynamic finite-element analysis suggest that buckling is the mechanism behind the generation of harmonics. We found good agreement between the level of second harmonic relative to the fundamental measured at 20 MHz and the Rayleigh–Plesset model predictions. Finite-element simulations extended these findings to a non-spherical geometry, confirmed that the acoustic buckling pressure corresponds to the critical pressure under hydrostatic conditions and support the hypothesis of limited gas flow across the GV shell during the compression phase in the frequency range investigated. From simulations, estimates of GV bandwidth-limited scattering indicate that a single GV has a scattering cross section comparable to that of a red blood cell. These findings will inform the development of GV-based contrast agents and pulse sequences to optimize their detection with ultrasound.

      PubDate: 2017-03-09T16:22:24Z
      DOI: 10.1016/j.ultrasmedbio.2016.12.020
  • Evaluation of Coronary Artery Disease Using Myocardial Elastography with
           Diverging Wave Imaging: Validation against Myocardial Perfusion Imaging
           and Coronary Angiography
    • Authors: Julien Grondin; Marc Waase; Alok Gambhir; Ethan Bunting; Vincent Sayseng; Elisa E. Konofagou
      Abstract: Publication date: Available online 28 February 2017
      Source:Ultrasound in Medicine & Biology
      Author(s): Julien Grondin, Marc Waase, Alok Gambhir, Ethan Bunting, Vincent Sayseng, Elisa E. Konofagou
      Myocardial elastography (ME) is an ultrasound-based technique that can image 2-D myocardial strains. The objectives of this study were to illustrate that 2-D myocardial strains can be imaged with diverging wave imaging and differ, on average, between normal and coronary artery disease (CAD) patients. In this study, 66 patients with symptoms of CAD were imaged with myocardial elastography before a nuclear stress test or an invasive coronary angiography. Radial cumulative strains were estimated in all patients. The end-systolic radial strain in the total cross section of the myocardium was significantly higher in normal patients (17.9 ± 8.7%) than in patients with reversible perfusion defect (6.2 ± 9.3%, p < 0.001) and patients with significant (−0.9 ± 7.4%, p < 0.001) and non-significant (3.7 ± 5.7%, p < 0.01) lesions. End-systolic radial strain in the left anterior descending, left circumflex and right coronary artery territory was found to be significantly higher in normal patients than in CAD patients. These preliminary findings indicate that end-systolic radial strain measured with ME is higher on average in healthy persons than in CAD patients and that ME has the potential to be used for non-invasive, radiation-free early detection of CAD.

      PubDate: 2017-03-09T16:22:24Z
      DOI: 10.1016/j.ultrasmedbio.2017.01.001
  • Usefulness of the Continuous-Wave Doppler-Derived Pulmonary
           Arterial–Right Ventricular Pressure Gradient Just before Atrial
           Contraction for the Estimation of Pulmonary Arterial Diastolic and Wedge
    • Authors: Michito Murayama; Taisei Mikami; Sanae Kaga; Kazunori Okada; Takuma Hioka; Nobuo Masauzi; Masahiro Nakabachi; Hisao Nishino; Shinobu Yokoyama; Mutsumi Nishida; Hiroyuki Iwano; Mamoru Sakakibara; Satoshi Yamada; Hiroyuki Tsutsui
      Abstract: Publication date: Available online 27 February 2017
      Source:Ultrasound in Medicine & Biology
      Author(s): Michito Murayama, Taisei Mikami, Sanae Kaga, Kazunori Okada, Takuma Hioka, Nobuo Masauzi, Masahiro Nakabachi, Hisao Nishino, Shinobu Yokoyama, Mutsumi Nishida, Hiroyuki Iwano, Mamoru Sakakibara, Satoshi Yamada, Hiroyuki Tsutsui
      In our new echocardiographic method, pulmonary regurgitant velocity immediately before right atrial (RA) contraction is used to estimate pulmonary artery diastolic pressure (PADP) and mean PA wedge pressure (MPAWP). Our aim here was to compare the usefulness of this new method with that of the conventional method, which uses pulmonary regurgitant velocity at end diastole. We studied 55 consecutive patients who underwent echocardiography and right-sided heart catheterization. The pulmonary regurgitant velocities just before RA contraction and at end diastole were measured to obtain echocardiographic estimates of PADP (EPADPpreA and EPADPED, respectively) by adding the pressure gradients to the echocardiographically estimated RA pressure. Compared with EPADPED, EPADPpreA correlated better with PADP (r = 0.87) and MPAWP (r = 0.80), and direct fixed biases were detected for EPADPED but not for EPADPpreA. The area under the receiver operating characteristic curve distinguishing patients with MPAWP ≥18 mm Hg was greater for EPADPpreA (0.97) than for E/e′ (0.94) and E/A (0.83). EPADPpreA is thus useful in estimating PADP and MPAWP in patients with heart disease.

      PubDate: 2017-03-09T16:22:24Z
      DOI: 10.1016/j.ultrasmedbio.2017.01.006
  • What Help Could Ultrasound Elastography Give to the Diagnosis of Breast
           Papillary Lesions?
    • Authors: Lu-Jing Li; Ji-Yi Yao; Xin-Chuan Zhou; Xin-Bao Zhao; Wen-Jing Zhong; Bing Ou; Bao-Ming Luo; Shao-Yun Hao; Hui Zhi
      Abstract: Publication date: Available online 27 February 2017
      Source:Ultrasound in Medicine & Biology
      Author(s): Lu-Jing Li, Ji-Yi Yao, Xin-Chuan Zhou, Xin-Bao Zhao, Wen-Jing Zhong, Bing Ou, Bao-Ming Luo, Shao-Yun Hao, Hui Zhi
      On the basis of results of our previous studies and the findings of other scholars, the most common histologic type of false-positive diagnosis with strain elastography (SE) was papilloma. The objectives of our study were to evaluate whether SE could contribute to conventional ultrasound differentiation between benign and malignant papillary lesions and between papillary lesions and other common benign breast lesions. Data on 89 papillary lesions at our hospital, including 74 benign and 15 malignant papillary lesions, were included in our study. In addition, 198 non-papillary benign tumors were selected as the control group, including 126 fibroadenomas and 72 cases of fibrocystic mastopathy. All patients gave written informed consent. All patients with breast lesions underwent conventional ultrasound and SE examination. Breast Imaging Recording and Data System (BI-RADS) category and SE score were compared with respect to sensitivity, specificity and accuracy in differentiating between benign and malignant papillary lesions. We then explored the possibility of using BI-RADS combined with SE to differentiate papillary lesions from non-papillary benign tumors. For differentiating between benign and malignant papillary lesions, the area under the receiver operating characteristic curve (AUC) of BI-RADS was 0.568, whereas the AUC values of SE score, strain ratio and BI-RADS combined with SE were 0.517, 0.584 and 0.509, respectively (p > 0.05). For differentiating between papillary lesions and non-papillary benign lesions, the AUC of BI-RADS combined with SE was 0.835, which was higher than the values for BI-RADS (0.775) and SE (SE score: 0.648, strain ratio: 0.661) (p < 0.001). The specificity and accuracy of BI-RADS combined with SE were significantly higher than those for BI-RADS alone without a decrease in sensitivity (p < 0.05). SE could not improve the diagnostic efficiency of BI-RADS in differentiating between benign and malignant papillary lesions. However, BI-RADS combined with SE could improve the specificity of BI-RADS without decrease in sensitivity for differentiating breast papillary lesions from non-papillary benign lesions.

      PubDate: 2017-03-09T16:22:24Z
      DOI: 10.1016/j.ultrasmedbio.2017.01.004
  • Ultrasound Image Classification of Ductal Carcinoma in Situ (DCIS) of the
           Breast: Analysis of 705 DCIS Lesions1
    • Authors: Takanori Watanabe; Takuhiro Yamaguchi; Hiroko Tsunoda; Setsuko Kaoku; Eriko Tohno; Hidemitsu Yasuda; Kanako Ban; Koichi Hirokaga; Kumiko Tanaka; Takeshi Umemoto; Toshitaka Okuno; Yasuhisa Fujimoto; Shuichi Nakatani; Jun Ito; Ei Ueno
      Abstract: Publication date: Available online 24 February 2017
      Source:Ultrasound in Medicine & Biology
      Author(s): Takanori Watanabe, Takuhiro Yamaguchi, Hiroko Tsunoda, Setsuko Kaoku, Eriko Tohno, Hidemitsu Yasuda, Kanako Ban, Koichi Hirokaga, Kumiko Tanaka, Takeshi Umemoto, Toshitaka Okuno, Yasuhisa Fujimoto, Shuichi Nakatani, Jun Ito, Ei Ueno
      The Japan Association of Breast and Thyroid Sonology (JABTS) proposed, in 2003, a conceptual classification system for non-mass abnormalities to be applied in addition to the conventional concept of masses, to facilitate detecting ductal carcinoma in situ (DCIS) lesions. The aim of this study was to confirm the utility of this system and to clarify the distribution of these findings in DCIS lesions. Data on 705 surgically treated DCIS lesions from 16 institutions in Japan were retrospectively reviewed. All 705 DCIS lesions could be classified according to the JABTS classification system. The most frequent findings were hypo-echoic areas in the mammary gland (48.6%), followed by solid masses (28.0%) and duct abnormalities (10.2%) or mixed masses (8.1%). Distortion (1.3%), clustered microcysts (1.4%) and echogenic foci without a hypo-echoic area (2.5%) were uncommon. These results suggest that the concept of non-mass abnormalities is useful in detecting DCIS lesions.

      PubDate: 2017-03-09T16:22:24Z
      DOI: 10.1016/j.ultrasmedbio.2017.01.008
  • Semi-quantitative Strain Ratio Determined Using Different Measurement
           Methods: Comparison of Strain Ratio Values and Diagnostic Performance
           Using One- versus Two-Region-of-Interest Measurement
    • Authors: Jung Hyun Yoon; Mi Kyung Song; Eun-Kyung Kim
      Abstract: Publication date: Available online 24 February 2017
      Source:Ultrasound in Medicine & Biology
      Author(s): Jung Hyun Yoon, Mi Kyung Song, Eun-Kyung Kim
      We evaluated the agreement and diagnostic performance of strain ratio values using measurements made with one and two user-defined regions of interest (ROIs) on breast elastography. Two hundred forty-three breast masses of 226 women (mean age: 48.2 y) were included. Ultrasonography (US) and elastography images of the masses were recorded. Strain ratio was measured twice on the same elastography image; strain ratio 1, applying one ROI at the target mass for measurement, and strain ratio 2, applying one ROI at the target mass and another ROI as reference strain. The two strain ratio measurements were in substantial agreement, with an intra-class correlation coefficient of 0.655 (95% confidence interval: 0.577–0.722). Specificity, positive predictive value and accuracy (cutoffs: 2.66 and 2.35) were significantly improved for US combined with the two strain ratio measurements (all p values < 0.05). Strain ratios measured using one or two user-defined ROIs were in substantial agreement, both contributing to the improved diagnostic performance of breast US.

      PubDate: 2017-03-09T16:22:24Z
      DOI: 10.1016/j.ultrasmedbio.2017.01.005
  • Common Carotid Artery Diameter, Blood Flow Velocity and Wave Intensity
           Responses at Rest and during Exercise in Young Healthy Humans: A
           Reproducibility Study
    • Authors: Nicola Pomella; Eurico Nestor Wilhelm Neto Wilhelm; Christina Kolyva; José González-Alonso; Mark Rakobowchuk; Ashraf W. Khir
      Abstract: Publication date: Available online 23 February 2017
      Source:Ultrasound in Medicine & Biology
      Author(s): Nicola Pomella, Eurico Nestor Wilhelm Neto Wilhelm, Christina Kolyva, José González-Alonso, Mark Rakobowchuk, Ashraf W. Khir
      The aim of this study was to assess the reproducibility of non-invasive, ultrasound-derived wave intensity (WI) in humans at the common carotid artery. Common carotid artery diameter and blood velocity of 12 healthy young participants were recorded at rest and during mild cycling, to assess peak diameter, change in diameter, peak velocity, change in velocity, time derivatives, non-invasive wave speed and WI. Diameter, velocity and WI parameters were fairly reproducible. Diameter variables exhibited higher reproducibility than corresponding velocity variables (intra-class correlation coefficient [ICC] = 0.79 vs. 0.73) and lower dispersion (coefficient of variation [CV] = 5% vs. 9%). Wave speed had fair reproducibility (ICC = 0.6, CV = 16%). WI energy variables exhibited higher reproducibility than corresponding peaks (ICC = 0.78 vs. 0.74) and lower dispersion (CV = 16% vs. 18%). The majority of variables had higher ICCs and lower CVs during exercise. We conclude that non-invasive WI analysis is reliable both at rest and during exercise.

      PubDate: 2017-03-09T16:22:24Z
      DOI: 10.1016/j.ultrasmedbio.2016.12.018
  • Computer-Based Algorithmic Determination of Muscle Movement Onset Using
           M-Mode Ultrasonography
    • Authors: Andrew J. Tweedell; Courtney A. Haynes; Matthew S. Tenan
      Abstract: Publication date: Available online 22 February 2017
      Source:Ultrasound in Medicine & Biology
      Author(s): Andrew J. Tweedell, Courtney A. Haynes, Matthew S. Tenan
      The study purpose was to evaluate the use of computer-automated algorithms as a replacement for subjective, visual determination of muscle contraction onset using M-mode ultrasonography. Biceps and quadriceps contraction images were analyzed visually and with three different classes of algorithms: pixel standard deviation (SD), high-pass filter and Teager Kaiser energy operator transformation. Algorithmic parameters and muscle onset threshold criteria were systematically varied within each class of algorithm. Linear relationships and agreements between computed and visual muscle onset were calculated. The top algorithms were high-pass filtered with a 30 Hz cutoff frequency and 20 SD above baseline, Teager Kaiser energy operator transformation with a 1200 absolute SD above baseline and SD at 10% pixel deviation with intra-class correlation coefficients (mean difference) of 0.74 (37.7 ms), 0.80 (61.8 ms) and 0.72 (109.8 ms), respectively. The results suggest that computer automated determination using high-pass filtering is a potential objective alternative to visual determination in human movement science.

      PubDate: 2017-03-09T16:22:24Z
      DOI: 10.1016/j.ultrasmedbio.2016.12.019
  • Sonoelastomics for Breast Tumor Classification: A Radiomics Approach with
           Clustering-Based Feature Selection on Sonoelastography
    • Authors: Qi Zhang; Yang Xiao; Jingfeng Suo; Jun Shi; Jinhua Yu; Yi Guo; Yuanyuan Wang; Hairong Zheng
      Abstract: Publication date: Available online 21 February 2017
      Source:Ultrasound in Medicine & Biology
      Author(s): Qi Zhang, Yang Xiao, Jingfeng Suo, Jun Shi, Jinhua Yu, Yi Guo, Yuanyuan Wang, Hairong Zheng
      A radiomics approach to sonoelastography, called “sonoelastomics,” is proposed for classification of benign and malignant breast tumors. From sonoelastograms of breast tumors, a high-throughput 364-dimensional feature set was calculated consisting of shape features, intensity statistics, gray-level co-occurrence matrix texture features and contourlet texture features, which quantified the shape, hardness and hardness heterogeneity of a tumor. The high-throughput features were then selected for feature reduction using hierarchical clustering and three-feature selection metrics. For a data set containing 42 malignant and 75 benign tumors from 117 patients, seven selected sonoelastomic features achieved an area under the receiver operating characteristic curve of 0.917, an accuracy of 88.0%, a sensitivity of 85.7% and a specificity of 89.3% in a validation set via the leave-one-out cross-validation, revealing superiority over the principal component analysis, deep polynomial networks and manually selected features. The sonoelastomic features are valuable in breast tumor differentiation.

      PubDate: 2017-03-09T16:22:24Z
      DOI: 10.1016/j.ultrasmedbio.2016.12.016
  • Investigation of Ultrasound-Measured Flow Velocity, Flow Rate and Wall
           Shear Rate in Radial and Ulnar Arteries Using Simulation
    • Authors: Xiaowei Zhou; Chunming Xia; Gandy Stephen; Faisel Khan; George A. Corner; Peter R. Hoskins; Zhihong Huang
      Abstract: Publication date: Available online 21 February 2017
      Source:Ultrasound in Medicine & Biology
      Author(s): Xiaowei Zhou, Chunming Xia, Gandy Stephen, Faisel Khan, George A. Corner, Peter R. Hoskins, Zhihong Huang
      Parameters of blood flow measured by ultrasound in radial and ulnar arteries, such as flow velocity, flow rate and wall shear rate, are widely used in clinical practice and clinical research. Investigation of these measurements is useful for evaluating accuracy and providing knowledge of error sources. A method for simulating the spectral Doppler ultrasound measurement process was developed with computational fluid dynamics providing flow-field data. Specific scanning factors were adjusted to investigate their influence on estimation of the maximum velocity waveform, and flow rate and wall shear rate were derived using the Womersley equation. The overestimation in maximum velocity increases greatly (peak systolic from about 10% to 30%, time-averaged from about 30% to 50%) when the beam–vessel angle is changed from 30° to 70°. The Womersley equation was able to estimate flow rate in both arteries with less than 3% error, but performed better in the radial artery (2.3% overestimation) than the ulnar artery (15.4% underestimation) in estimating wall shear rate. It is concluded that measurements of flow parameters in the radial and ulnar arteries with clinical ultrasound scanners are prone to clinically significant errors.

      PubDate: 2017-03-09T16:22:24Z
      DOI: 10.1016/j.ultrasmedbio.2016.12.015
  • Anatomical Regurgitant Orifice Detection and Quantification from 3-D
           Echocardiographic Images
    • Authors: Miguel Sotaquirá; Mauro Pepi; Gloria Tamborini; Enrico G. Caiani
      Abstract: Publication date: Available online 16 February 2017
      Source:Ultrasound in Medicine & Biology
      Author(s): Miguel Sotaquirá, Mauro Pepi, Gloria Tamborini, Enrico G. Caiani
      The vena contracta and effective regurgitant orifice area (EROA) are currently used for the clinical assessment of mitral regurgitation (MR) from 2-D color Doppler imaging. In addition to being highly user dependent and having low repeatability, these methods do not represent accurately the anatomic regurgitant orifice (ARO), which affects the adequate assessment of MR patients. We propose a novel method for semi-automatic detection and quantitative assessment of the 3-D ARO shape from 3-D transesophageal echocardiographic images. The algorithm was tested on a set of 25 patients with MR, and compared with EROA for validation. Results indicate the robustness of the proposed approach, with low variability in relation to different settings of user-defined segmentation parameters. Although EROA and ARO exhibited a good correlation (r = 0.8), relatively large biases were measured, indicating that EROA probably underestimates the real shape and size of the regurgitant orifice. Along with the higher reproducibility of the proposed approach, this highlights the limitations of current clinical approaches and underlines the importance of accurate assessment of the ARO shape for diagnosis and treatment in MR patients.

      PubDate: 2017-03-09T16:22:24Z
      DOI: 10.1016/j.ultrasmedbio.2016.12.017
  • Transesophageal Echocardiography in Swine: Establishment of a Baseline
    • Authors: Katharina Huenges; Saskia Pokorny; Rouven Berndt; Jochen Cremer; Georg Lutter
      Abstract: Publication date: Available online 16 February 2017
      Source:Ultrasound in Medicine & Biology
      Author(s): Katharina Huenges, Saskia Pokorny, Rouven Berndt, Jochen Cremer, Georg Lutter
      The porcine model is a commonly used animal model in cardiovascular research. Along with new innovative operative techniques, choice of the optimal imaging technique is crucial. Transesophageal echocardiography (TEE) is a reliable imaging tool is highly important in a large number of experimental evaluations. But so far, TEE data for swine are limited, and few standard values have been established for the porcine model. The experience and baseline results for TEE in 45 swine are presented in this study. A full TEE examination was conducted in 45 German landrace or German large white swine, with an average body weight of 49 ± 3 kg, before experimental off-pump mitral valved stent implantation. Additionally hemodynamic measurements were evaluated. The valve implantation procedure was guided solely by real-time 3-D TEE. Baseline values of standard echocardiographic parameters are provided and, where appropriate, compared with human reference values. TEE proved to be an adequate imaging technique in this experimental porcine animal model. The baseline TEE and hemodynamic parameters established for the widely used porcine model can serve as a reference in future studies.

      PubDate: 2017-03-09T16:22:24Z
      DOI: 10.1016/j.ultrasmedbio.2016.12.011
  • Impact of Filling Gas on Subharmonic Emissions of Phospholipid Ultrasound
           Contrast Agents
    • Authors: Emma Kanbar; Damien Fouan; Charles A. Sennoga; Alexander A. Doinikov; Ayache Bouakaz
      Abstract: Publication date: Available online 14 February 2017
      Source:Ultrasound in Medicine & Biology
      Author(s): Emma Kanbar, Damien Fouan, Charles A. Sennoga, Alexander A. Doinikov, Ayache Bouakaz
      Subharmonic signals backscattered from gas-filled lipid-shelled microbubbles have generated significant research interest because they can improve the detection and sensitivity of contrast-enhanced ultrasound imaging. However, the emission of subharmonic signals is strongly characterized by a temporal dependence, the origins of which have not been sufficiently elucidated. The features that influence subharmonic emissions need to be identified not only to better develop next-generation microbubble contrast agents, but also to develop more efficient subharmonic imaging (SHI) modes and therapeutic strategies. We examined the effect of microbubble filling gas on subharmonic emissions. Phospholipid shelled-microbubbles with different gaseous compositions such as sulfur hexafluoride (SF6), octafluoropropane (C3F8) or decafluorobutane (C4F10), nitrogen (N2)/C4F10 or air were insonated using a driving frequency of 10 MHz and peak negative pressure of 450 kPa, and their acoustic responses were tracked by monitoring both second harmonic and subharmonic emissions. Microbubbles were first acoustically characterized with their original gas and then re-characterized after substitution of the original gas with air, SF6 or C4F10. A measureable change in intensity of the subharmonic emissions with a 20- to 40-min delayed onset and increasing subharmonic emissions of the order 12–18 dB was recorded for microbubbles filled with C4F10. Substitution of C4F10 with air eliminated the earlier observed delay in subharmonic emissions. Significantly, substitution of SF6 for C4F10 successfully triggered a delay in the subharmonic emissions of the resultant agents, whereas substitution of C4F10 for SF6 eliminated the earlier observed suppression of subharmonic emissions, clearly suggesting that the type of filling gas contained in the microbubble agent influences subharmonic emissions in a time-dependent manner. Because our agents were dispersed in air-stabilized phosphate-buffered saline, these results suggest that the diffusivity of the gas from the agent to the surrounding medium is correlated with the time-dependent evolution of subharmonic emissions.

      PubDate: 2017-03-09T16:22:24Z
      DOI: 10.1016/j.ultrasmedbio.2016.12.013
  • Effect of Low-Intensity Cavitation on the Isolated Human Thoracic Artery
           in Vitro
    • Authors: Algimantas Bubulis; Vida Garalienė; Vytautas Jurėnas; Jonas Navickas; Saulius Giedraitis
      Abstract: Publication date: Available online 10 February 2017
      Source:Ultrasound in Medicine & Biology
      Author(s): Algimantas Bubulis, Vida Garalienė, Vytautas Jurėnas, Jonas Navickas, Saulius Giedraitis
      Reported here are the results of an experimental study on the response to low-intensity cavitation induced by low-frequency (4–6 W/cm2, 20 kHz and 32.6 kHz) ultrasound of isolated human arterial samples taken during conventional myocardial revascularization operations. Studies have found that low-frequency ultrasound results in a significant (48%–54%) increase in isometric contraction force and does not depend on the number of exposures (10 or 20) or the time passed since the start of ultrasound (0, 10 and 20 min), but does depend on the frequency and location (internal or external) of the blood vessels for the application of ultrasound. Diltiazem (an inhibitor of slow calcium channels) and carbachol (an agonist of muscarinic receptors) used in a concentration-dependent manner did not modify the relaxation dynamics of smooth muscle affected by ultrasound. Thus, ultrasound conditioned to the augmentation of the isometric contraction force the smooth muscle of blood vessels and did not improve endothelial- and calcium channel blocker-dependent relaxation.

      PubDate: 2017-03-09T16:22:24Z
      DOI: 10.1016/j.ultrasmedbio.2016.12.007
  • Guidelines for Cleaning Transvaginal Ultrasound Transducers Between
    • Authors: Jacques S. Abramowicz; David H. Evans; J. Brian Fowlkes; Karel Maršal; Gail terHaar
      Abstract: Publication date: Available online 9 February 2017
      Source:Ultrasound in Medicine & Biology
      Author(s): Jacques S. Abramowicz, David H. Evans, J. Brian Fowlkes, Karel Maršal, Gail terHaar
      The purpose of this article is to provide guidance regarding the cleaning and disinfection of transvaginal ultrasound probes. These recommendations are also applicable to transrectal probes.

      PubDate: 2017-03-09T16:22:24Z
      DOI: 10.1016/j.ultrasmedbio.2017.01.002
  • Effect of Carbon Dioxide on the Twinkling Artifact in Ultrasound Imaging
           of Kidney Stones: A Pilot Study
    • Authors: Julianna C. Simon; Yak-Nam Wang; Bryan W. Cunitz; Jeffrey Thiel; Frank Starr; Ziyue Liu; Michael R. Bailey
      Abstract: Publication date: Available online 9 February 2017
      Source:Ultrasound in Medicine & Biology
      Author(s): Julianna C. Simon, Yak-Nam Wang, Bryan W. Cunitz, Jeffrey Thiel, Frank Starr, Ziyue Liu, Michael R. Bailey
      Bone demineralization, dehydration and stasis put astronauts at increased risk of forming kidney stones in space. The color-Doppler ultrasound “twinkling artifact,” which highlights kidney stones with color, can make stones readily detectable with ultrasound; however, our previous results suggest twinkling is caused by microbubbles on the stone surface which could be affected by the elevated levels of carbon dioxide found on space vehicles. Four pigs were implanted with kidney stones and imaged with ultrasound while the anesthetic carrier gas oscillated between oxygen and air containing 0.8% carbon dioxide. On exposure of the pigs to 0.8% carbon dioxide, twinkling was significantly reduced after 9–25 min and recovered when the carrier gas returned to oxygen. These trends repeated when pigs were again exposed to 0.8% carbon dioxide followed by oxygen. The reduction of twinkling caused by exposure to elevated carbon dioxide may make kidney stone detection with twinkling difficult in current space vehicles.

      PubDate: 2017-03-09T16:22:24Z
      DOI: 10.1016/j.ultrasmedbio.2016.12.010
  • Value of Shear Wave Elastography in the Diagnosis of Gouty and Non-gouty
    • Authors: Yuanjiao Tang; Feng Yan; Yujia Yang; Xi Xiang; Liyun Wang; Lingyan Zhang; Li Qiu
      Abstract: Publication date: Available online 7 February 2017
      Source:Ultrasound in Medicine & Biology
      Author(s): Yuanjiao Tang, Feng Yan, Yujia Yang, Xi Xiang, Liyun Wang, Lingyan Zhang, Li Qiu
      Our aim was to analyze the diagnostic performance of shear wave elastography (SWE) in the diagnosis of gouty arthritis (GA) and non-gouty arthritis (non-GA). Thirty-nine patients in the GA group and 55 patients in the non-GA group were included in the study. Based on the echo intensity of the joint lesions, the GA group was subdivided into hypo-echoic GA, slightly hyper-echoic GA and hyper-echoic GA subgroups. Quantitative SWE features were evaluated and receiver operating characteristic analysis was performed. On the basis of the study, the elastic modulus (E max), mean elastic modulus (E mean), minimum elastic modulus (E min) and elastic modulus standard deviation (E SD) were significantly higher in the GA group than in the non-GA group and were highest in the hyper-echoic GA subgroup (p < 0.01 for all). E min, E mean and E max were significantly higher in the hyper-echoic GA subgroup than in the hypo-echoic GA subgroup and non-GA group (p < 0.001 for all), and E SD was significantly higher in the hyper-echoic GA subgroup than in the non-GA group (p = 0.001). E min, E mean, E max and E SD were higher in the hypo-echoic GA subgroup than in the non-GA group, and the differences were significant (p < 0.001 for all). Based on the hypo-echoic GA subgroup and non-GA group, areas under the receiver operating characteristic curves for the prediction of GA were 0.749 for E min, 0.877 for E mean, 0.896 for E max and 0.886 for E SD, with optimal cutoff values of 29.40 kPa for E min, 45.35 kPa for E mean, 67.54 kPa for E max and 7.85 kPa for E SD. Our results indicate that SWE can differentially diagnose GA and non-GA, especially when the ultrasound manifestations are not typical.

      PubDate: 2017-03-09T16:22:24Z
      DOI: 10.1016/j.ultrasmedbio.2016.12.012
  • Editorial Advisory Board
    • Abstract: Publication date: February 2017
      Source:Ultrasound in Medicine & Biology, Volume 43, Issue 2

      PubDate: 2017-03-09T16:22:24Z
  • Breast Lesion Elastography Region of Interest Selection and Quantitative
           Heterogeneity: A Systematic Review and Meta-Analysis
    • Authors: Molly A.B.; Blank James Antaki
      Abstract: Publication date: Available online 14 October 2016
      Source:Ultrasound in Medicine & Biology
      Author(s): Molly A.B. Blank, James F. Antaki
      In this systematic review and meta-analysis, we report measured elasticities of benign and malignant breast pathologies from shear wave elastography (SWE), quantitatively confirm the effect of the selected region of interest (ROI) on these measures and test the hypothesis that a metric of heterogeneity based on the mean and maximum elasticity can improve specificity of diagnosis. The elasticities of benign, malignant and specific pathologic states are reported from 22 publications encompassing 2989 patients, identified from a structured search of the literature from May to September 2015. Twelve articles were included in a meta-analysis that grouped results by the method of ROI selection to discriminate between different pathologies. We observe a significant correlation between the method of selection of ROI for malignant mean (p < 0.001) and maximum (p = 0.027) elasticities, but no correlation with benign measures. We define a quantitative heterogeneity parameter, the “stiffness gradient,” computed from the mean and maximum measured elasticities. The stiffness gradient out-performed the current standard maximum elasticity metric in stratifying malignancy risk by a margin of 15% for the partial ROI, and 42% for the maximized ROI. An anecdotal example of improved differentiation using the stiffness gradient on pathology-specific lesions is also provided. These results quantitatively indicate that the method of ROI selection in SWE not only has a significant impact on the resulting mean reported elasticity of a lesion, but may provide some insight into lesion heterogeneity. Our results suggest that further exploration of quantitative heterogeneity is warranted to improve the specificity of diagnosis.

      PubDate: 2016-11-03T22:14:49Z
School of Mathematical and Computer Sciences
Heriot-Watt University
Edinburgh, EH14 4AS, UK
Tel: +00 44 (0)131 4513762
Fax: +00 44 (0)131 4513327
Home (Search)
Subjects A-Z
Publishers A-Z
Your IP address:
About JournalTOCs
News (blog, publications)
JournalTOCs on Twitter   JournalTOCs on Facebook

JournalTOCs © 2009-2016