Transient elastography in DAA era. Relation between post‐SVR LSM and histology

The natural history of HCV chronic infection has drastically changed after direct‐acting antiviral treatment. Due to the high sustained virological response (SVR) achieved, noninvasive estimation of liver fibrosis regression has become a major key point. The present study tries to evaluate the relation between liver histology and liver stiffness measurement (LSM) by transient elastography (TE) after SVR.     

The stratification of cirrhosis

Cirrhosis is traditionally seen as an irreversible stage of chronic liver disease although its clinical course may last several years. Overall, the clinical management of patients with cirrhosis is based on the observation of clinical events mostly related to complications of portal hypertension. Each event of cirrhosis decompensation has clear prognostic implications although it is not precisely predictable. In practice, the advancement in the knowledge of the mechanisms responsible for disease progression is not yet translated in clinical tools allowing the stratification of the cirrhotic stage according to pathophysiological mechanisms. This article provides a review of the main clinical and histopathological features of liver cirrhosis that are relevant for its clinical stratification together with the advancements provided by the introduction of non‐invasive measures of portal hypertension. Other clinical aspects that have a major impact on the quality of life and the possibility of liver transplantation are also discussed.     

Noninvasive assessment of liver fibrosis in children with chronic hepatitis C: Shear wave elastography and APRI versus liver biopsy

Background and study aimsHepatitis C virus (HCV) is a major cause of chronic hepatitis. Although liver histopathological examination remains the reference standard for liver fibrosis assessment, noninvasive means of assessment such as shear wave elastography (SWE) and aspartate aminotransferase–platelet ratio index (APRI) have been developed to reduce the need for biopsy. We evaluated the efficacy of SWE and APRI versus liver biopsy for liver fibrosis assessment in children with chronic HCV infection.Patients and methodsFibrosis staging was performed in 46 children (35 boys, 11 girls; mean age: 15.52 ± 2.71 years) with liver biopsy-proven chronic HCV infection according to the METAVIR system. SWE was performed within 6 months of liver biopsy. APRI scores were calculated using data collected on the day of biopsy.ResultsEighteen children had no or mild fibrosis (<F2, 39.1%) and 28 had significant fibrosis (≥F2, 60.9%), with a significant difference between the corresponding mean APRI scores (0.43 ± 0.23 vs 1.26 ± 1.24; p = 0.043). The APRI scores exhibited a significant correlation with the METAVIR stage (r = 0.630; p < 0.001). The SWE values were significantly higher in those with significant fibrosis than in those with no or mild fibrosis (10.43 vs 4.26 kPa; p < 0.000). These values exhibited significant correlations with the METAVIR stage and APRI score (r = 0.863 and 0.544, respectively; both p < 0.001). For differentiating significant fibrosis, the sensitivity, specificity and positive and negative predictive values for an APRI cutoff value of 0.62 were 46.43%, 94.4%, 92.9% and 53.1%, respectively, and these values for an SWE cutoff value of 7.6 kPa were 55.88%, 100%, 100% and 44.4%, respectively.ConclusionIn the clinical assessment of children, the APRI score and SWE can help differentiate between no or mild fibrosis and significant fibrosis. The routine use of SWE and APRI may help decrease the number of liver biopsies performed.     

Value of shear wave elastography with maximal elasticity in differentiating benign and malignant solid focal liver lesions

BACKGROUNDIt is important to differentiate benign and malignant focal liver lesions (FLLs) accurately. Despite the wide use and acceptance of shear wave elastography (SWE), its value for assessing the elasticity of FLLs and differentiating benign and malignant FLLs is still investigational. Previous studies of SWE for FLLs used mean elasticity as the parameter to reflect the stiffness of FLLs. Considering the inhomogeneity of tumor stiffness, maximal elasticity (Emax) might be the suitable parameter to reflect the stiffness of FLLs and to differentiate malignant FLLs from benign ones.AIMTo explore the value of SWE with Emax in differential diagnosis of solid FLLs.METHODSWe included 104 solid FLLs in 95 patients and 50 healthy volunteers. All the subjects were examined using conventional ultrasound (US) and virtual touch tissue quantification(VTQ) imaging. A diagnosis of benign or malignant FLL was made using conventional US. Ten VTQ values were acquired after 10 consecutive measurements for each FLL and each normal liver, and the largest value was recorded as Emax.RESULTSThere were 56 cases of malignant FLLs and 48 cases of benign FLLs in this study. Emax of malignant FLLs (3.29 ± 0.88 m/s) was significantly higher than that of benign FLLs (1.30 ± 0.46 m/s, P < 0.01) and that of livers in healthy volunteers (1.15 ± 0.17 m/s, P < 0.01). The cut-off point of Emax was 1.945, and the area under the curve was 0.978. The sensitivity and specificity of Emax were 92.9% and 91.7%, respectively, higher (but not significantly) than those of conventional US (80.4% for sensitivity and 81.3% for specificity). Combined diagnosis of conventional US and Emax using parallel testing improved the sensitivity to 100% with specificity of 75%.CONCLUSIONSWE is a convenient and easy method to obtain accurate stiffness information of solid FLLs. Emax is useful for differential diagnosis of FLLs, especially in combination with conventional US.     

Experimental model standardizing polyvinyl alcohol hydrogel to simulate endoscopic ultrasound and endoscopic ultrasound-elastography

BACKGROUND Endoscopic ultrasound(EUS) and endoscopic ultrasound elastography(EUS-E) simulation lessens the learning curve; however, models lack realism, diminishing competitiveness.AIM To standardize the mechanical properties of polyvinyl alcohol(PVA) hydrogel for simulating organs and digestive lesions.METHODS PVA hydrogel(Sigma Aldrich, degree of hydrolysis 99%) for simulating EUS/EUS-E lesions was investigated in Unidad de Investigación y Desarrollo Tecnológico at Hospital General de México "Dr. Eduardo Liceaga", Mexico City. We evaluated physical, contrast, elasticity and deformation coefficient characteristics in lesions, applying Kappa's concordance and satisfaction questionnaire(Likert 4-points).RESULTS PVA hydrogel showed stable mechanical properties. Density depended on molecular weight(MW) and concentration(C). PVA bblocks with the greatest density showed lowest tensile strength(r =-0.8, P = 0.01). Lesions were EUSgraphically visible. Homogeneous and heterogeneous examples were created from PVA blocks or PVA phantoms, exceeding(MW_2 = 146000-186000, C_9 = 15% and C_(10) = 20%) with a density under(MW_1 = 85000-124000, C_1 = 7% and C_2 = 9%). We calculated elasticity and deformation parameters of solid(blue) areas, contrasting with the norm(Kappa = 0.8; high degree of satisfaction).CONCLUSION PVA hydrogels were appropriate for simulating organs and digestive lesions using EUS/EUS-E, facilitating practice and reducing risk. Repetition amplified skills, while reducing the learning curve.     

Clinical Application of Transient Elastography in the Diagnosis of Liver Fibrosis: an Expert Panel Review and Opinion

Liver fibrosis evaluation is pivotal for treatment decisions and prognosis assessment in patients with chronic liver disease. Liver transient elastography (TE) is a newly developed non-invasive technique for diagnosis of liver fibrosis. It can assess the state of liver fibrosis by liver stiffness measurements, and offers better performance for the diagnosis of liver cirrhosis than serum biological markers. It has now been approved for clinical use in China. The aim of this review is to provide a guide for clinicians to apply this technique appropriately. The recommendations are made under the auspices of China Foundation for Hepatitis Prevention and Control, and have been prepared by a panel experts, who have reviewed and summarized the clinical studies on TE in order to develop these recommendations.     

剪切波超声弹性成像评估糖尿病周围神经病变

目的 探讨剪切波弹性成像对2型糖尿病胫神经形态学及硬度改变的评估价值。方法 利用高频超声与剪切波弹性成像技术检测2016年1月1日～2016年12月31日昆明医科大学第一附属医院收治的74例2型糖尿病［伴周围神经病变（n=39）、不伴周围神经病变（n=35）］及同期健康体检者（n=32）的双侧胫神经行高频超声探查及剪切波弹性成像,测量胫神经横截面积、杨氏模量最大值和平均值,再分别绘制ROC曲线,对比神经横截面积、杨氏模量最大值和平均值的诊断价值并计算最佳诊断界值。 结果 横截面积、杨氏模量最大值和平均值的曲线下面积分别为0.727、0.878、0.872,最佳诊断界值分别为0.19cm 2、60.6KPa、54.5Kpa。结论 剪切波弹性成像技术能量化神经硬度改变,从而评估糖尿病周围神经病变,对糖尿病周围神经病变具有良好的诊断价值。     

超声弹性成像技术在IgG4相关唾液腺炎诊断和随访中的应用

目的: 探讨超声弹性成像技术在IgG4相关唾液腺炎诊断和随访中的应用价值。方法: 回顾分析2018年5月—10月就诊于上海交通大学医学院附属第九人民医院口腔外科,诊断为IgG4相关唾液腺炎3例患者的临床资料。所有患者均接受口服小剂量糖皮质激素治疗,采用超声弹性成像技术应变率比值法和声辐射力脉冲成像法,对治疗前、后患者下颌下腺进行弹性超声检查,观察超声影像学特点及疗效。结果: 3例患者临床表现均为双侧下颌下腺无痛性肿大超过3个月,血清IgG和IgG4浓度均异常升高,下颌下腺活检病理及免疫组织化学染色结果提示符合IgG4相关唾液腺炎。治疗前弹性超声成像显示腺内大范围蓝色区域对应低回声区,应变率比值（SR）较正常腺体减小而剪切波速值（SWV）较正常腺体增大,表示该区域腺体质地比正常腺体明显较硬。所有患者经小剂量糖皮质激素治疗1个月后随访,临床表现原本肿大的下颌下腺明显消退,触诊质地软化,血清IgG和IgG4浓度明显下降,弹性超声显示蓝色区域范围明显缩小,黄色和绿色区域范围增大,对应SR增大而SWV减小,客观且半量化地反映腺体质地较治疗前软化。结论: 超声弹性成像技术通过测量SR或SWV,可以客观半量化地反映病变唾液腺质地。结合患者的临床表现、血清学指标和组织病理学表现,可以辅助IgG4相关唾液腺炎的诊断,并初步评价疾病的严重性和进展程度。