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11.
AIM: To assess quantitative endoscopic ultrasound (EUS)-guided elastography in the nodal staging of oesophago-gastric cancers.METHODS: This was a single tertiary centre study assessing 50 patients with established oesophago-gastric cancer undergoing EUS-guided fine needle aspiration biopsy (FNAB) of lymph nodes between July 2007 and July 2009. EUS-guided elastography of lymph nodes was performed before EUS-FNAB. Standard EUS characteristics were also described. Cytological determination of whether a lymph node was malignant or benign was used as the gold standard for this study. Comparisons of elastography and standard EUS characteristics were made between the cytologically benign and malignant nodes. The main outcome measure was the accuracy of elastography in differentiating between benign and malignant lymph nodes in oesophageal cancers.RESULTS: EUS elastography and FNAB were performed on 53 lymph nodes. Cytological malignancy was found in 23 nodes, one was indeterminate, one was found to be a gastrointestinal stromal tumor and 25 of the nodes were negative for malignancy. On 3 occasions insufficient material was obtained for analysis. The area under the curve for the receiver operating characteristic curve for elastography strain ratio was 0.87 (P < 0.0001). Elastography strain ratio had a sensitivity 83%, specificity 96%, positive predictive value 95%, and negative predictive value 86% for distinguishing between malignant and benign nodes. The overall accuracy of elastography strain ratio was 90%. Elastography was more sensitive and specific in determining malignant nodal disease than standard EUS criteria.CONCLUSION: EUS elastography is a promising modality that may complement standard EUS and help guide EUS-FNAB during staging of upper gastrointestinal tract cancer.  相似文献   
12.
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   
13.
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   
14.
《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   
15.
16.
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   
17.
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   
18.
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   
19.
PurposeTo determine the diagnosis performance of shear wave elastography in the differentiation of benign and malignant breast lesions and the factors influencing the elasticity values. To suggest an appropriate management of breast lesions using the ultrasound-elastography combination.Patients and methodsMonocentric retrospective study of 167 breast lesions classified by conventional ultrasound as BI-RADS category 3 or higher that underwent an elastography study and histological analysis.ResultsThe analysis of qualitative parameters, according to the classification established in this study, allows us to obtain a sensitivity of 91.1% and a specificity of 92.3%. These values are very close to or better than the quantitative parameters Emax and Emean. Different Emax thresholds values were established based on the long axis of the lesion and its palpable character, which appeared to be significant factors influencing elasticity. The management of breast lesions by combining ultrasound and elastography, as proposed here, allows us to keep the sensitivity of an ultrasound (96%), while doubling its specificity (86.2% versus 43.1%).ConclusionWith the complementary nature of their performance, the combination of conventional ultrasound and shear wave elastography can improve the management of breast lesions. The qualitative classification proposed appears to be relevant assistance in lesion characterization.  相似文献   
20.
Ultrasound elastography is an easy, relatively affordable, noninvasive method that can be used to assess for hepatic fibrosis. The aim of this article is to present an introduction to ultrasound elastography and provide case examples to show when its use can be beneficial.  相似文献   
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