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21.
AIM: To evaluate cut-off values and performance of acoustic radiation force impulse imaging (ARFI) using transient elastography [FibroScan© (FS)] as a reference.METHODS: Six hundred and six patients were enrolled in this study. All patients underwent liver stiffness measurement with FS (FS-LS) and ARFI (with shear wave velocity quantification; ARFI-SWV) and the performance of ARFI in comparison to FS was determined. Sixty-eight patients underwent liver biopsy.RESULTS: Significantly higher success rates for the determination of liver stiffness were found using ARFI as compared to FS [604/606 (99.7%) vs 482/606 (79.5%), P < 0.001]. ARFI-SWV correlated significantly with FS-LS (r = 0.920, P < 0.001). ARFI-SWV increased significantly with the stage of fibrosis (1.09 ± 0.13 m/s for patients with no significant fibrosis (FS-LS < 7.6 kPa); 1.46 ± 0.27 m/s for patients with significant liver fibrosis (7.6 < FS-LS ≤ 13.0 kPa); and 2.55 ± 0.77 m/s for patients with liver cirrhosis (FS-LS > 13.0 kPa)). ARFI-SWV cut-off values were identified for no significant fibrosis (1.29 m/s; sensitivity 91.4% and specificity 92.6%) and for liver cirrhosis (1.60 m/s; sensitivity 92.3% and specificity 96.5%). The optimal cut-off value for predicting liver fibrosis (F ≥ 2) was 1.32 m/s (sensitivity 87.0% and specificity 80.0%) and for liver cirrhosis (F4) 1.62 m/s (sensitivity 100% and specificity 85.7%), for patients who underwent liver biopsy. An excellent inter-and intraobserver reproducibility was observed for ARFI-SWV determinations.CONCLUSION: An ARFI-SWV cut-off value of 1.29 m/s seems to be optimal for patients with no significant liver fibrosis and 1.60 m/s for patients with liver cirrhosis.  相似文献   
22.
Varicoceles are the most common and treatable cause of male infertility. The pathophysiology of varicoceles primarily includes elevated temperature, adrenal hormone reflux, gonadotoxic metabolite reflux, altered testicular blood flow, antisperm antibody formation and oxidative stress. The diagnosis of a varicocele is mainly clinical. However, a Doppler ultrasound is used to obtain clinical data and to more accurately measure testicular size. Acoustic radiation force impulse (ARFI) is an additional technique to simultaneously show different areas with different densities in a colour‐coded image and a B‐mode or greyscale image. This can be used for structural analysis of testicular tissue and has become an additional method for detecting pathologic tissue alterations. We enrolled 30 patients who had clinically diagnosed with left varicoceles and male infertility (Group 1). All patients were evaluated by history taking, physical examination, a spermiogram and an endocrine profile. Thirty control patients (Group 2) were randomly chosen from patients who had applied to an andrology clinic for infertility; their physical examinations and laboratory results showed normal findings. Mean elastography results were significantly different between the groups, and significantly lower in patients who had varicoceles. The relationship between hormonal profiles and elastography parameters was calculated as statistically significant negative correlations between FSH and elasticity. Additionally, a negative correlation was determined between varicocele grade and elasticity of testes. In conclusion, our prospective study showed that ARFI imaging may be more useful than palpation for determining early damage of testicular structure by varicoceles.  相似文献   
23.
Ultrasound elastography produces strain images of compliant tissues under quasi-static compression. When a material is compressed, there are several parameters that affect the stress-distribution and, hence, the strain distribution in the material. The state of bonding of an inclusion to the background material is a critical parameter. Heretofore, in the field of elastography, the inclusion was considered to be firmly bonded to the background material and analytical solutions were derived for the elasticity problem involving simple geometries like circular inclusion (for two dimensional [2D]) and spherical inclusion (three dimensional [3D]). Under these conditions, simple analytical expressions relating the strain contrast to the modulus contrast were derived. However, it is known that the state of bonding of some tumors to their surrounding tissues depends on the type of the lesion. For example, benign lesions of the breast are known to be loosely bonded to the surrounding tissue, while malignant breast lesions are firmly bonded. In this study, we perform a parametric study using finite element modeling (FEM) to investigate the validity of the analytical expression relating the strain contrast to the modulus contrast, when the state of bonding at the inclusion/background interface spans a large dynamic range. The results suggest that estimated modulus contrast using the analytical expression is sensitive to the region-of-interest within the inclusion that is considered in the computation of the strain contrast. By considering the inclusion region lying along the axis of lateral symmetry instead of whole region of the inclusion, the estimated modulus contrast (obtained using the analytical expression present in the literature) can be computed to within a systematic error of 10% of the actual modulus contrast. Additional estimation errors are expected to accrue in experimental and in vivo conditions.  相似文献   
24.
目的观察常规超声、超声弹性成像以及18F-FDG PET/CT对乳腺良恶性病变的诊断价值。方法回顾性2019年1月至2020年2月在我院治疗的67例乳腺病变患者的临床资料。分析其影像学资料,比较常规超声、超声弹性成像以及18F-FDG PET/CT检查结果与病理学检查结果的一致性;以病理学检查为标准,比较三种检查对乳腺良恶性病变的诊断效能及诊断价值。结果18F-FDG PET/CT检查结果与病理学检查结果的一致性(Kappa=0.906)大于常规超声(Kappa=0.566)和超声弹性成像(Kappa=0.662);18F-FDG PET/CT鉴别乳腺良恶性病变的灵敏度及特异度高于常规超声,准确率高于常规超声、超声弹性成像(P<0.05);经ROC曲线分析得,18F-FDG PET/CT鉴别乳腺良恶性病变的AUC为0.966,大于常规超声(0.787)及超声弹性成像(0.838,P<0.05)。结论18F-FDG PET/CT鉴别乳腺良恶性病变的准确率高于常规超声、超声弹性成像,且其具有较高的诊断价值。  相似文献   
25.
《Foot and Ankle Surgery》2022,28(8):1279-1285
BackgroundAims of this study were: 1/ to evaluate the shear wave speed (SWS) properties of the anteroinferior tibiofibular ligament (AITFL) and the distal interosseous membrane (DIOM) in neutral, dorsal flexion and plantar flexion positions in a cohort of healthy adult volunteers; 2/ to assess the reliability and reproducibility of these measurements.MethodsBoth ankles were analyzed by shear wave elastography (SWE) in 20 healthy patients (10 females/10 males) standing on a hinge support with their ankles in neutral, 20° dorsal flexion and 30° plantar flexion positions. Stiffness of AITFL and DIOM was evaluated by SWS measurement.ResultsThe SWS of AITFL and DIOM were minimal in the plantar flexion position (4.28 m/s [2.65–5.11] and 3.35 m/s [1.69–4.55], respectively). It increased significantly for both ligaments in neutral position (4.69 m/s [3.53–5.71] and 3.81 m/s [1.91–4.74], respectively; p < 0.0001), and reached their maximum values in dorsal flexion (6.58 m/s [5.23–8.34] and 4.79 m/s [3.07–6.19], respectively; p < 0.0001). There was no correlation between each ligament regardless the positions. SWS of AITFL was independent of demographic characteristics analyzed. SWS of DIOM was negatively correlated with height in dorsal flexion (ρ = ?0.35; p = 0.03) and in plantar flexion (ρ = ?0.37; p = 0.02). Female gender was associated with increased DIOM SWS in neutral (p = 0.005), dorsal flexion (p = 0.003), and plantar flexion (p = 0.001) positions. Moreover, foot morphology (foot arch, hind foot frontal deviation) did not impact AITFL nor DIOM SWS. Inter- and intra-observer measurements were all good or excellent.ConclusionThe AITFL and DIOM, stabilizers of the distal tibiofibular syndesmosis, increase in stiffness while dorsal flexion increases. This study describes a reliable and reproducible protocol to assess their stiffness by SWE, and defines a corridor of normality.  相似文献   
26.
27.
目的探讨正常人甲状腺双侧叶腺体的超声弹性硬度、甲状腺与同侧胸锁乳突肌弹性硬度的比值及年龄、性别对甲状腺弹性硬度有无影响。方法对50例正常人分别进行甲状腺横断面、纵断面超声弹性扫查,分析比较双侧叶甲状腺腺体纵横断面时弹性硬度及甲状腺与同侧胸锁乳突肌弹性硬度比值,比较不同年龄段、不同性别时甲状腺组织的弹性硬度。结果正常人甲状腺左右侧叶横断面弹性硬度、纵断面弹性硬度比较,差异无统计学意义(尸〉0.05);在正常人群中,不同年龄、性别组甲状腺腺体超声弹性硬度差异无统计学意义(P〉O.05)。结论甲状腺双侧叶腺体弹性指数及其与同侧肌肉弹性指数的比值较为稳定,年龄、性别对甲状腺腺体硬度无影响。  相似文献   
28.
目的探讨超声弹性成像在诊断乳腺疾病中的临床应用价值。方法分析近年来本院收治60例乳腺患者的超声弹性成像检查资料,利用弹性成像5分评分法,对弹性成像诊断结果与手术病理对照进行分析。结果病理结果:良性43例(55个结节),恶性17例(20个结节)。超声弹性成像的诊断恶性病变敏感性为85.0%,特异性为89.1%,准确性为88.0%。结论超声弹性成像对鉴别乳腺肿瘤的良、恶性有其独到的优势,可提高对乳腺恶性肿瘤的诊断,值得临床推广应用。  相似文献   
29.
Introduction and objectivesNon-alcoholic steatohepatitis (NASH) is a severe form of non-alcoholic fatty liver disease (NAFLD) that can progress to liver cirrhosis, liver failure and hepatocellular carcinoma. It is the second leading cause of liver transplant in the US. We aim to investigate the prevalence, demographics and risk factors NASH patients in the US.Patients and methodsWe used a large database (Explorys IBM) that aggregates electronic health records from 26 nationwide healthcare systems. We identified adults with NASH between 2010-2020. Demographics including age, gender and race were collected. NASH risk factors including Diabetes Millets (DM), Hyperlipidemia (HLD), Hypertension (HTN) and Obesity were also collected. Cochran-Armitage test was used to assess the statistical significance of year-by-year trend. Univariable and multivariable logistic regression were used to estimate the odds ratio (OR) of risk factors.ResultsNASH annual prevalence rate increased from 1.51% in 2010 to 2.79% in 2020 (p < 0.0001). The proportion of patients with NASH by gender was 54.1% female vs 45.9% male (OR 1.04 [0.91-1.11]). Caucasian had higher odds of NASH than non-Caucasian (OR 1.42 [1.31-1.54]). NASH is strongly associated with DM and obesity (OR 18.61 [17.35-19.94]) and (OR 20.97 [17.87-23.21]), respectively. Other components of metabolic syndrome were associated with NASH to a lesser degree; HTN (OR 3.24 [3.20-3.28]) and HLD (OR 4.93 [4.85-4.01]).ConclusionThe prevalence of NASH has significantly increased in the US in the last decade. This is likely related to the increased prevalence of risk factors as well as increased awareness of the disease.  相似文献   
30.
Background and study aimsPregnancy in association with cirrhosis is a rather uncommon and highly risky situation for both mother and child. We aim to study all factors and the utility of liver stiffness (LS) measurement by Acoustic Radiation Force Impulse elastography (ARFI) to predict hepatic decompensation in pregnant cirrhotic patients.Patients and methodsWe prospectively recruited 224 pregnant women at the multidisciplinary clinic of liver disease with pregnancy, Cairo University. LS was measured using ARFI (Siemens ACUSON S3000 ultrasound system) during the second trimester and 8–12 weeks post-delivery. The outcome of pregnancy and the incidence of hepatic decompensation were assessed.ResultsOur cohort comprised 128 normal pregnancies, 37 patients with pregnancy-related liver disease (Intrahepatic cholestasis (n = 6), preeclampsia (n = 23), and hyperemesis gravidarum (n = 8)) and 59 patients with an established chronic liver disease not related to pregnancy. In all patients, LS significantly decreased after delivery from 1.19 m/s to 0.94 m/s (P < 0.001). In multivariate analysis, LS was an independent predictor for the outcome of pregnancy in all patients (odds ratio (OR) = 5.442 (3.01–6.82), cut-off = 1.21 m/s). Patients with cirrhosis, mean LS was 1.57 ± 0.66 m/s and 26 (44%) patients had hepatic decompensation (hepatocellular jaundice (n = 8), ascites (n = 9) and variceal bleeding (n = 6)). In multivariate analysis; LS, platelets, albumin, and bilirubin were independent predictors of decompensation post-delivery and the OR for LS was 6.141(4.32–7.98). The optimal cut off value of LS to predict decompensation was 1.46 m/s (8.4 kPa) with AUROC of 0.827.ConclusionLS can be used to predict hepatic decompensation after delivery in pregnant women with manifest cirrhosis.  相似文献   
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