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71.
72.
Yanrong Guo Changfeng Dong Haoming Lin Xinyu Zhang Huiying Wen Yuanyuan Shen Tianfu Wang Siping Chen Yingxia Liu Xin Chen 《Ultrasound in medicine & biology》2017,43(11):2619-2628
The aim of this study is to evaluate the utility of acoustic radiation force impulse (ARFI) elastography for assessing hepatic fibrosis stage and non-alcoholic fatty liver disease (NAFLD) severity, as well as the relationship among hepatic histologic changes using shear wave velocity (SWV). Animal models with various degrees of NAFLD were established in 110 rats. The right liver lobe was processed and embedded in a fabricated gelatin solution (porcine skin). Liver mechanics were measured using SWV induced by acoustic radiation force. Among the histologic findings, liver elasticity could be used to differentiate normal rats from rats with simple steatosis (SS) as well as distinguish SS from non-alcoholic steatohepatitis (NASH), with areas under the receiver operating characteristic curves (AUROC) of 0.963 (95% confidence interval = 0.871–0.973) and 0.882 (95% confidence interval = 0.807–0.956), respectively. For NAFLD rats, the diagnostic performance of ARFI elastography in predicting significant fibrosis (F ≥ 2) had an AUROC of 0.963. For evaluating steatosis severity, we found a progressive increase in ARFI velocity proportional to steatotic severity in NAFLD rat models, but we observed no significant differences for steatotic severity after excluding the rats with fibrosis. ARFI elastography may be used to differentiate among degrees of severity of NAFLD and hepatic fibrotic stages in NAFLD rat models. 相似文献
73.
Impact of anthropometric features on the applicability and accuracy of FibroScan® (M and XL) in overweight/obese patients
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74.
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Matthias Aurich Patrick Fuchs Matthias Müller-Hennessen Lorenz Uhlmann Matthias Niemers Sebastian Greiner Tobias Täger Kristof Hirschberg Philipp Ehlermann Benjamin Meder Lutz Frankenstein Evangelos Giannitsis Hugo A. Katus Derliz Mereles 《Journal of the American Society of Echocardiography》2018,31(6):733-742
76.
Jing Gao Wen He Li-Juan Du Johnson Chen David Park Michael Wells Brian Fowlkes Michael ODell 《Ultrasound in medicine & biology》2018,44(9):1931-1940
We prospectively investigated the feasibility of using quantitative ultrasound imaging (QUI) to assess the biceps brachii muscle (BBM) in individuals with chronic post-stroke spasticity. To quantify muscle echogenicity and stiffness, we measured QUI parameters (gray-scale pixel value and shear wave velocity [SWV, m/s]) of the BBM in three groups: 16 healthy BBMs; 12 post-stroke, non-spastic BBMs; and 12 post-stroke, spastic BBMs. The QUI results were compared with the Modified Ashworth Scale and Tardieu Scale. A total of 20 SWVs were measured in each BBM, once at elbow in 90° flexion and again at maximally achievable extension using acoustic radiation force impulse imaging. BBM pixel value was measured in gray-scale images captured at 90° elbow flexion using ImageJ software. Statistical analyses included analysis of variance for examining the difference in SWV and pixel values among the three groups; Bonferroni correction for testing the difference in SWV and pixel values in a paired group; t-test for examining the difference in SWV values measured at two elbow angles; and Pearson correlation coefficient for analyzing the correlation of QUI to Modified Ashworth Scale and Tardieu Scale. SWV significantly differed between spastic BBMs and non-spastic or healthy BBMs. For pixel values, each of the three groups significantly differed from the others at elbow 90° flexion. The difference in SWV measured between the two elbow angles was also significant (p?<0.01). A strong negative correlation was found between SWV and passive range of motion (R2?=??0.88, p?<0.0001) in spastic upper limbs. These results suggest that the use of QUI is feasible in quantitative assessment of spastic BBM. 相似文献
77.
Liver stiffness measurement predicts high‐grade post‐hepatectomy liver failure: A prospective cohort study
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78.
An ultrasound elasticity microscope was used to map 3-D strain volume in an ex vivo porcine cornea to illustrate its ability to measure the mechanical properties of this tissue. Mechanical properties of the cornea play an important role in its function and, therefore, also in ophthalmic diseases such as kerataconus and corneal ectasia. The ultrasound elasticity microscope combines a tightly focused high-frequency transducer with confocal scanning to produce high-quality speckle over the entire volume of tissue. This system and the analysis were able to generate volume maps of compressional strain in all three directions for porcine corneal tissue, more information than any previous study has reported. Strain volume maps indicated features of the cornea and mechanical behavior as expected. These results constitute a step toward better understanding of corneal mechanics and better treatment of corneal diseases. 相似文献
79.
80.
《Expert Review of Gastroenterology & Hepatology》2013,7(5):501-511
Prognosis of patients with chronic liver disease is determined by the extent and progression of liver fibrosis, which may ultimately lead to hepatocellular carcinoma (HCC). Liver biopsy (LB) is regarded as the gold standard to estimate the extent of liver fibrosis. However, because LB has several limitations, the foremost being its invasiveness, several non-invasive methods for assessing liver fibrosis have been proposed. Of these, transient elastography (TE) provides an accurate representation of the extent of liver fibrosis. Furthermore, recent studies have focused on the usefulness of TE for assessing the risk of HCC development and HCC recurrence after curative treatment, and developed novel models to calculate the risk of HCC development based on TE findings. These issues are discussed in this expert review. 相似文献