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11.
肝纤维化是临床上各类慢性肝病进行性发展的重要病理过程之一,可进一步发展为肝硬化甚至肝癌。肝纤维化的早期诊断对预防各类肝病发展为肝硬化及肝癌具有重要意义。肝穿刺活检是诊断肝纤维化的“金标准”,但其具有创伤性,易引起多种并发症,目前无法作为常规筛查手段。近年来,超声检查技术作为一种无创性肝纤维化诊断方法在临床上得到越来越多的应用,并取得了诸多进展。本文就超声技术在肝纤维化诊断方面的研究现状作一综述。  相似文献   
12.
目的:探讨剪切波弹性成像(shear wave elastography,SWE)与细针穿刺洗脱液甲状腺球蛋白(fine-needle aspiration washout thyroglobulin,FNA-Tg)对甲状腺乳头状癌侧颈部淋巴结转移的诊断价值。方法:回顾性分析159例经病理证实为甲状腺乳头状癌(papillary thyroid carcinoma,PTC)的患者资料,对颈部211枚可疑淋巴结进行常规超声、SWE参数平均值(Emean)、FNA-Tg检查,以术后病理结果为金标准,比较各检测方法的诊断效能。结果:(1)SWE Emean转移组[(50.96±27.66) kPa]高于非转移组[(32.20±17.34) kPa],差异有统计学意义(t=8.761,P<0.01)。受试者工作特征(receiver operating characteristic,ROC)曲线分析表明,SWE Emean最佳诊断阈值为40.42 kPa时对PTC颈部淋巴结转移预测价值较高,曲线下面积(area under...  相似文献   
13.
目的:评价剪切波弹性成像(shear wave elastography,SWE)测量育龄期健康未育女性宫颈杨氏模量值的可重复性。方法:由同一名接受过SWE检测培训的高年资医师于同一天不同时间点,前后2次对100名处于育龄期但未育的健康女性宫颈行剪切波弹性成像,测量时选取宫颈4个位点:内口前唇(anterior lip of the inner mouth,IA)、内口后唇(posterior lip of the inner mouth,IP)、外口前唇(anterior lip of the outer mouth,EA)及外口后唇(posterior lip of the outer mouth,EP),获取育龄期健康未育女性宫颈杨氏模量值。使用组内相关系数(interclass correlation coefficient,ICC)评价检查者内可重复性,同时绘制BlandAltman散点图评价测量一致性。结果:宫颈4个测量位点的前后2次测值均无统计学差异(P>0.05);宫颈IA、EA、EP处杨氏模量值的组内相关系数分别为0.828、0.785、0.768,提示组内可重...  相似文献   
14.
医学成像技术在最近几年中有了飞速的发展,新的成像方法不断涌现,已有的成像方式不断完善。从平面到立体、从局部到整体、从静态到动态、从形态到功能已成为医学成像技术发展的趋势。文中简要介绍分子成像、近红外热成像等新的成像方式。  相似文献   
15.
Summary. Before the introduction of viral inactivation procedures and viral screening of plasma‐products, haemophiliacs were at high risk of infection with HCV. Those who acquired HCV infection in the 1980s, and are still alive today, may have developed significant liver fibrosis or cirrhosis. However, liver biopsy has not routinely been utilized in the evaluation of haemophiliacs with HCV in Denmark. The aim of this study was to investigate the prevalence of significant fibrosis/cirrhosis among haemophiliacs as evaluated by transient elastography (TE). Cross‐sectional investigation of adult patients with haemophilia A or B. TE with liver stiffness measurements (LSM) ≥8 kPa were repeated after 4–6 weeks. Significant fibrosis and cirrhosis was defined as measurements ≥8 kPa or ≥12 kPa respectively. Among 307 patients with haemophilia A or B registered at the two Haemophilia centres, 141(46%) participate in this study. Forty (28.4%) had chronic hepatitis C, 33 (23.4%) past hepatitis C and 68 (48.2%) had never been infected, at screening LSM ≥8 kPa were found in 45.7%, 24.7% and 4.6% respectively. Among patients with chronic hepatitis C significant fibrosis was confirmed in 17.1% and cirrhosis in 2.9% by repeated LSM ≥8 and ≥12 kPa respectively. The median TE‐value in never HCV‐infected haemophiliacs was comparable with what has been found in healthy non‐haemophiliacs. In Danish haemophiliacs where liver biopsy has not routinely been used for assessing severity of liver fibrosis, LSM identified advanced liver disease in one‐fifth of cases that had not been recognized during clinical follow‐up.  相似文献   
16.
17.
《HIV clinical trials》2013,14(2):110-115
Abstract

Although liver biopsy still remains the globally accepted gold standard for assessing liver disease, the more recent introduction of noninvasive markers in form of blood tests as well as transient elastography have led to the development of new algorithms for assessing liver disease in HIV and hepatitis coinfected individuals. Other hot topics in coinfection include need and outcome for liver organ transplantation in the increasing number of HIV-infected patients with end-stage liver disease as well as development of new agents and strategies for treatment of hepatitis B or C coinfection.  相似文献   
18.
The present study investigated the potential of ultrasound shear wave elastography (SWE) in assessment of muscle stiffness in muscle injury. SWE was performed on the injured muscle in 30 New Zealand rabbits that were randomly assigned to three groups: the contusion group, which was not treated with an efficient therapeutic strategy after muscle injury; the treatment group, which was treated with a therapeutic scheme after muscle injury; and the healthy group, which was not injured and served as a control. Both the mean Young's modulus (Emean) and the maximum Young's modulus (Emax) were obtained pre-injury and 0.5, 1, 3, 5, 7, 14 and 28 d post-injury. At these time points, a rabbit in each group was randomly selected for biopsy for histopathological observation as well as comparison with Young's modulus. Eventually, all muscle tissues were collected for histologic analysis of collagen fiber formation. The contusion group had the highest Young's modulus, followed by the treatment group and then the healthy group (p < 0.05). In both the contusion and treatment groups, Emean and Emax gradually increased within 1–3 d after injury, followed by a gradual decrease. Compared with the healthy group, histopathologic analysis of the contusion and treatment groups revealed the myofibril destruction process, inflammatory reaction and myofibril regeneration. The amount of collagen fibers in the contusion group was maximal compared with the treated and healthy groups (p?=?0.001 and p < 0.001, respectively). There were more collagen fibers in the treatment group than in the healthy group (p?=?0.003). The abundance of collagen fibers was positively correlated with the value of Young's modulus (Emean: r?=?0.706, p < 0.001; Emax: r?=?0.761, p < 0.001). Thus, SWE can be used to detect pathologic changes in injured muscle and to monitor therapeutic effects.  相似文献   
19.
20.
The aim was to evaluate the influence of food intake on liver stiffness measurement (LSM), performed with 2-D shear wave elastography (Logiq E9, GE Medical Systems, Wauwatosa, WI, USA). One hundred healthy volunteers were prospectively enrolled. Mean age was 25.8 (19–55) y, and mean body mass index was 22.43 (17.3–30.8) kg/m². Patients fasted for at least 3 h and subsequently ingested a liquid meal of 800 kcal. Liver stiffness and portal vein velocity were measured before and after food intake. Food intake resulted in significantly higher LSM values compared with baseline LSM (5.74 ± 0.94 kPa vs. 4.80 ± 0.94 kPa, p < 0.001). On multiple linear regression analysis, body mass index was significantly positively correlated with the LSM increase after food intake (p?=?0.01). No correlation between the increase in LSM and the increase in post-prandial portal vein velocity was observed (r?=?0.09). In summary, food intake has a significant influence on LSM. There is an 11% risk of misclassifying non-fasting, healthy patients as having significant fibrosis.  相似文献   
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