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991.
Johanne Seguin Nathalie Mignet Heldmuth Latorre Ossa Mickaël Tanter Jean-Luc Gennisson 《Ultrasound in medicine & biology》2017,43(10):2352-2361
A recent ultrasound imaging technique—shear wave elastography—showed its ability to image and quantify the mechanical properties of biological tissues, such as prostate or liver tissues. In the present study this technique was used to evaluate the relationship among tumor growth, stiffness and reduction of treatment with combretastatin (CA4 P) in allografted colon tumor CT26 in mice. During 12 d, CT26 tumor growth (n = 52) was imaged by ultrasound, and shear modulus was quantified, showing a good correlation between tumor volume and stiffness (r = 0.59). The treatment was initiated at d 12 and monitored every d during 4 d. Following the treatment, the tumor volume had decreased, while the elasticity of the tumor volume remained steady throughout the treatment. After segmentation using the shear modulus map, a detailed analysis showed a decrease in the stiffness after treatment. This reduction in the mechanical properties was shown to correlate with tissue reorganization, particularly, fibrosis and necrosis, assessed by histology. 相似文献
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早产是全球5岁以下儿童死亡的第二大原因,目前已成为衡量一个国家的健康指标之一。有效的早产筛查手段能提高早产的防治。超声因具有无辐射、适用性广及操作简单等优点,已作为临床评估早产的手段。本文主要对超声技术评估妊娠宫颈在预测早产的应用进行综述。 相似文献
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997.
Tudor-Voicu Moga Ana Maria Stepan Corina Pienar Felix Bende Alina Popescu Roxana Șirli Mirela Dănilă Ioan Sporea 《Ultrasound in medicine & biology》2018,44(8):1627-1637
The aim of the study described here was to evaluate the reproducibility of a new shear-wave elastography (SWE) technique, 2-D SWE.GE, and the impact of ultrasound experience in acquiring reliable measurements, as no official recommendations are available for this system. Elastographic measurements (EMs) were obtained in 60 patients using 2-D-SWE with the GE Logiq E9. Three examiners with different levels of experience in ultrasound-based elastography performed 10 valid EMs on each subject: a novice (C.P.) who had no experience in liver elastography and had performed fewer than 50 ultrasound examinations; an elastography expert (A.M.S.) who had more than 1 y of liver elastographic experience in four elastographic methods and had performed more than 1000 ultrasonography examinations; and an ultrasound expert (T.M.) who had no experience in liver elastography and had performed more than 1000 ultrasound examinations. Medians and interquartile ranges were calculated (m/s). We used the inter-class correlation coefficient and Bland–Altman plots with 95% lower and upper limits of agreement to assess the inter- and intra-observer reproducibility of 2-D-SWE.GE measurements. The final study group included 60 patients, 56.7% women and 43.3% men, with a mean age of 33.08?±?13.83 y and mean body mass index of 22.85?±?4.04?kg/m2. In this group, 73.3% were healthy volunteers and 26.7% had compensated liver cirrhosis. We did not find significant differences between EMs taken by the examiners overall and across study groups. The overall agreement between examiners was excellent: 0.915 (95% confidence interval [CI]: 0.870–0.946). The agreement between the novice and the experienced examiners, respectively, was good to excellent (novice and ultrasound expert: 0.908, 95% CI: 0.846–0.945; novice and elastography expert: 0.885, 95% CI: 0.808–0.931). The intra-observer reproducibility for each of the examiners was excellent; however, the inter-class correlation coefficients were higher for the examiners more experienced in elastography: 0.936 (95% CI: 0.896–0.963) versus 0.966 (95% CI: 0.943–0.980) versus 0.984 (95% CI: 0. 973–0.991). The good ICCs for the median values indicate that 2-D-SWE.GE is a reproducible method. Ultrasound experience did not significantly influence the results. 相似文献
998.
Zeping Huang Jian Zheng Jie Zeng Xiaoli Wang Tao Wu Rongqin Zheng 《Ultrasound in medicine & biology》2014,40(11):2549-2555
Real-time shear wave elastography (SWE) is a novel two-dimensional elastographic method that is used to estimate the severity of liver fibrosis. However, the normal range of liver stiffness (LS) and the possible factors that influence SWE are not well understood. The aims of the current study are to define the normal range of LS in healthy subjects and to explore the factors that may affect SWE. A total of 509 healthy subjects underwent SWE to determine the stiffness of their livers, and the effects of gender, age and body mass index (BMI) on LS were analyzed. The effects of different factors on SWE, including the testing position, measurement depth and size of the region of interest (ROI), were analyzed in 137 subjects. SWE imaging was successfully performed in 502 healthy subjects (98.6%, 502/509). The mean value of the SWE measurements in 502 individuals was 5.10 ± 1.02 kPa, and the 95% confidence interval was 5.02–5.19 kPa (range: 2.4–8.7 kPa). We found that the detective position within the liver had a significant impact on the liver stiffness measurement (LSM), and the lowest coefficient of variation (CV = 8%) was obtained for LSMs made at segment V. LS was greater at a depth >5 cm (5.78 ± 1.66 kPa) compared with depths ≤5 cm (4.66 ± 0.77 kPa, p < 0.001); LS was also greater in men than in women (5.45 ± 1.02 kPa vs. 4.89 ± 0.96 kPa, p < 0.001). However, there were no significant differences in the LS values regarding the size of the ROI, age or BMI (all p > 0.05). The mean LS value in all 502 healthy subjects was 5.10 ± 1.02 kPa. The mean LS value obtained by SWE was not influenced by the size of the ROI, age or BMI, but the mean value was significantly influenced by the different segments of the liver, the detection depth and gender. 相似文献
999.
Using transient elastography to predict hepatocellular carcinoma recurrence after radiofrequency ablation
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1000.
Jie Zeng Zeping Huang Jieyang Jin Jian Zheng Tao Wu Rongqin Zheng 《Ultrasound in medicine & biology》2018,44(1):85-93
This study assessed the diagnostic accuracy of 2-D shear wave elastography (2-D-SWE) for the non-invasive staging of liver fibrosis and compared the findings with those for biochemical markers (the aspartate aminotransferase-to-platelet index and fibrosis-4 index) of liver fibrosis in patients with elevated alanine aminotransferase (ALT) levels (>5?×?the upper limit of normal). Patients with chronic liver diseases and elevated ALT levels who underwent liver biopsy were consecutively included. Receiver operating characteristic (ROC) curves were constructed to assess overall accuracy and to identify optimal cutoff values. After exclusions, data from 105 patients were analyzed. The areas under the ROC curves (AUROCs) for significant fibrosis, severe fibrosis and cirrhosis were 0.83, 0.86 and 0.91, respectively. The optimal cutoff values for predicting significant fibrosis, severe fibrosis and cirrhosis were 10.6, 13.2 and 17.6?kPa, respectively. The AUROCs of 2-D-SWE were significantly higher than those of biochemical markers for predicting significant fibrosis, severe fibrosis and cirrhosis (all p values?<?0.05). Therefore, the diagnostic performance of 2-D-SWE in assessing liver fibrosis stages in patients with elevated ALT levels was promising. The optimal cutoff values were increased but appropriate for this cohort because the baseline levels of liver stiffness measurements were increased in these patients, even in the absence of fibrosis. 相似文献