A threshold value in Shear Wave elastography to rule out malignant thyroid nodules: A reality?

Objectives

To evaluate hability of a threshold value in ShearWave™ elastography to rule out malignant thyroid nodules while studying its pertinence in association with morphological signs.

Equipment and methods

148 patients (110 women and 38 men; 52.5 y.o. 15.8) referred for surgery of thyroid nodules underwent standard ultrasound as well as elastography. Characteristics of the morphological signs and maximum elastographic index were calculated in relation to histology. Association of morphological signs alone and then of elastography was also evaluated. One hundred and fifty one nodules were studied on a double-blind basis.

Results

297 nodules were studied. Thirty-five cancers were detected (11.6%). Elastographic index was higher in malignant nodules (115 kPa 60.4) than in benign nodules (41 kPa 25.8) (p < 0.001, Student's t-test). Cut off value of 66 kPa was the best to discriminate malignant nodules with a sensitivity of 80% (CI 95%, 62.5; 90.9) and a specificity of 90.5% (CI 95%, 86.1; 93.6) (p = 0.0001). Association of elastography and morphological ultrasound signs presented a sensitivity of 97% (CI 95%, 83.3; 99.8) and a negative predictive value of 99.5% (CI 95%, 95.6; 99.9). Interobserver reproducibility proved to be excellent with an interclass correlation of 0.97 (CI 95%, 0.96; 0.98) (p < 0.001).

Conclusion

The 66 kPa threshold in Shear Wave elastography is the best ultrasound sign to rule out malignant thyroid nodules. The method is simple, quantitative, reproducible and usable in the study of nodules larger than 3 cm. Progress must still be made in the study of calcified nodules and follicular tumors.     

Elastographic assessment of liver fibrosis in children: A prospective single center experience

Background

The assessment of liver damage in various disease states relies on a combination of clinical findings, biochemical parameters and invasive tests such as liver biopsy. The ultrasound elastography has emerged as a potential alternative test, providing quantifiable information on the elasticity/stiffness of the examined-tissues. We assessed the performance of ultrasound elastography using real-time Acoustic Radiation Force Imaging (ARFI) technology in evaluating the degree of liver fibrosis in children with and without liver disease.

Methods

Children aged 0–18 years, hospitalized in the Emergency Clinical County Hospital Tg. Mures, Romania, between September 15, 2010 and January 15, 2011, were eligible for the study. Four groups were recruited as follow: patients with liver disease in the setting of various malignant disorders, children with non-malignant liver disease, overweight and obese children and healthy controls. The liver tissue elasticity was assessed in each individual using Shear Wave Velocity (SWV). Biochemical tests included transaminase levels. 19 children with chronic liver disease underwent biopsies. SWV was measured globally and separately for the liver-segments 1 and 8. Correlations between the SWV and laboratory test were established using non-parametric Spearman correlation test.

Results

A total of 103 children underwent liver ultrasound elastographic assessments. Of these, 39 had malignancies, 19 had various chronic liver diseases, 13 had nonalcoholic fatty liver disease (NAFLD), and 32 were healthy controls. The transaminase values differed significantly between children with liver diseases and controls. In normal controls SWV values in the 1st segment were significantly lower compared to those in the in 8th segment of the liver (p = 0.0216). In the group with hepatic steatosis, the SWV values were statistically higher compared to those in healthy controls. Positive statistical correlations have been established between AST and SWV in the group of children with NAFLD and those with malignancies (p = 0.0032, p = 0.0045).

Conclusions

Quantification of liver fibrosis by ARFI method correlates with the histological fibrosis stage in children with chronic liver disease and NAFLD. Clinical applications of this method in the diagnosis of pediatric liver disease deserve further study.     

An improved quantitative measurement for thyroid cancer detection based on elastography

Objective

To evaluate color thyroid elastograms quantitatively and objectively.

Materials and methods

125 cases (56 malignant and 69 benign) were collected with the HITACHI Vision 900 system (Hitachi Medical System, Tokyo, Japan) and a liner-array-transducer of 6–13 MHz. Standard of reference was cytology (FNA—fine needle aspiration) or histology (core biopsy). The original color thyroid elastograms were transferred from red, green, blue (RGB) color space to hue, saturation, value (HSV) color space. Then, hard area ratio was defined. Finally, a SVM classifier was used to classify thyroid nodules into benign and malignant. The relation between the performance and hard threshold was fully investigated and studied.

Results

The classification accuracy changed with the hard threshold, and reached maximum (95.2%) at some values (from 144 to 152). It was higher than strain ratio (87.2%) and color score (83.2%). It was also higher than the one of our previous study (93.6%).

Conclusion

The hard area ratio is an important feature of elastogram, and appropriately selected hard threshold can improve classification accuracy.     

Prospective evaluation of acoustic radiation force impulse technology in the differentiation of thyroid nodules: accuracy and interobserver variability assessment

Purpose

The aim of this study is to assess the diagnostic efficacy and interobserver agreement of acoustic radiation force impulse (ARFI) elasticity imaging in differentiating thyroid nodules.

Methods

In our study, 74 consecutive patients (52 females, 22 males; age range 27–77 years, mean: 41 years) with 82 thyroid nodules (60 benign nodules, and 22 malignant) were examined by two radiologists with different experience. Patients underwent either cytology using fine needle aspiration cytology or thyroid surgery. The diagnostic performance of the two operators at ARFI with sensitivity, specificity, positive predictive and negative predictive value, and ROC curves was estimated. Inter-reader variability between the two operators was defined using Cohen’s k.

Results

According to receiver operating characteristics ROC curves (AUROC = 0.86 for observer 1; 0.81 for observer 2) sensitivity, specificity, PPV and NPV of reader 1 and 2 were respectively: 90, 75, 90.91 and 96.55 %; (cut-off value of shear wave: 2.455 m/s); 90, 72, 90 and 96.90 % (cut-off value shear wave: 2.365 m/s). Concordance between the two operators was good (k = 0.755).

Conclusions

This work is a feasibility study evaluating ARFI imaging. Its results suggest that ARFI imaging is a reproducible method which can be utilized with good diagnostic performance in the thyroid for discriminating benign and malignant nodules using the cut-off value of 2.455 m/s. However, larger studies are needed to validate this method.     

乳腺癌超声弹性成像面积比与其组织学分级、临床分期关系的初步研究

目的探讨乳腺超声弹性成像面积比（AR）对乳腺癌患者病情发展及预后评估的参考价值。方法回顾性分析105例经病理结果证实的乳腺癌患者临床资料,术前行乳腺常规超声及超声弹性成像检查,分析乳腺癌患者不同组织学分级间、不同临床分期间AR参数的变化情况。结果术前以AR≥1.5为诊断恶性的标准,73例恶性,诊断符合率为69.52%。超声弹性成像AR在各组织学分级、临床分期组间差异有统计学意义（P〈0.05）：组织学分级Ⅰ～Ⅲ级的AR值分别为1.210±0.018、1.470±0.126、1.600±0.028,临床分期Ⅰ～Ⅳ期AR值分别为1.230±0.056、1.540±0.017、1.580±0.025及1.620±0.023,即AR在组织分级较高及临床分期较晚时增大。结论 AR可为乳腺癌病情发展及预后评估提供有价值的参考信息。     

Impact of the New Definition of Metabolic Associated Fatty Liver Disease on the Epidemiology of the Disease

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乳腺占位性病变弹性评分3分患者年龄与肿瘤良恶性相关性的探讨

目的探讨乳腺占位性病变弹性评分3分患者年龄与肿瘤良恶性的相关性。方法对180例乳腺占位性病变弹性评分3分病例进行随访,按年龄对结果进行分析。结果 180例中恶性65例,良性115例,恶性中24～40岁7例,40～60岁53例,60岁以上5例。40～60岁与24～40岁组比较,良恶性病例比例存在统计学意义（P〈0.05）。结论弹性成像评分3分病例不同年龄组肿瘤恶性率存在差异性。     

超声弹性成像技术与二维灰阶＋CDFI超声诊断乳腺疾病对照研究

目的探讨超声弹性成像与二维灰阶＋CDFI超声在诊断乳腺疾病中的价值。方法以手术病理为诊断标准,对比分析超声弹性成像与二维灰阶＋CDFI超声诊断乳腺疾病的准确性。结果超声弹性成像诊断乳腺恶性病变的敏感性、特异性和准确性分别为83％、98％、95％。二维灰阶＋CDFI超声诊断乳腺恶性病变的敏感性、特异性和准确性分别为82％、78％、79％。结论超声弹性成像诊断乳腺病变的准确性高于二维灰阶＋CDFI超声．但两者结合可望提高乳腺良恶性病变诊断的准确性。     

不同年龄段人群正常肝脏弹性成像定量的相关性分析

目的:探讨基于弹性成像技术的组织弥散定量分析软件评估不同年龄段健康者人群肝脏硬度弹性图像的特征量及弹性指数。方法:采用彩色多普勒超声诊断仪,应用组织弥散定量分析软件分析1 800名健康体检者的肝脏硬度,得到11个弹性图像的特征量,包括应变均值、标准差、蓝色区域比例(%)、复杂度、峰度、偏度、对比度、均等性、杂乱性、一致性、相关性,分析4组年龄段弹性图像特征量的差异。结果:4个年龄段肝脏弹性成像定量分析测值除均等性、峰值、杂乱性、一致性外,其他指标如复杂度、应变均值、标准偏差、偏度、蓝色面积%、对比度均有统计学意义(P<0.01),有较好的重复性。结论:因年龄的不同,健康人肝脏的硬度不同,肝脏的硬度随年龄呈递增状态。     

超声弹性成像技术评价周围性面瘫针灸疗效的临床应用价值

摘要 目的 探讨超声弹性成像技术动态评估周围性面瘫针灸治疗效果的临床应用价值。方法 选取2019年11月至2020年9月于重庆市中医院接受针灸治疗的50例周围性单侧面瘫患者为研究对象,应用超声弹性成像技术评估针灸治疗过程中6个时间点面部表情肌（额肌、降口角肌、降下唇肌）的弹性模量值,同时临床面神经功能评分评估面瘫程度。线性相关分析不同治疗时间点,患侧弹性模量值与临床面神经功能评分的相关性。结果 面瘫患者患侧表情肌（额肌、降口角肌、降下唇肌）的弹性模量值,随着针灸治疗次数增加,弹性模量值逐渐降低,6个检测时间点差异比较均具有统计学意义（P＜0.01),且治疗前7天下降速率最快;而对照组表情肌的弹性模量值无明显变化。与弹性模量值改变相一致的是,患侧面神经功能临床评分随着治疗时间增加,评分逐渐升高,治疗后7天内评分上升速率增快,差异具有统计学意义（P＜0.01）。相关性分析发现,弹性模量值与临床面神经功能评分呈负相关（r=-0.546, P＜0.001; r=-0.757, P＜0.001; r=-0.683, P＜0.001）。结论 利用超声弹性成像技术可动态评估针灸治疗前后面部表情肌群的弹性变化,与面神经功能临床评分相关,可为面瘫治疗效果评估提供重要影像学依据。