超声实时剪切波弹性成像技术评估兔非酒精性脂肪性肝病的实验研究

目的探讨超声实时剪切波弹性成像(SWE)技术评估兔非酒精性脂肪性肝病(NAFLD)及肝纤维化的价值。方法共60只8周龄新西兰大白兔,通过喂以普通饲料和高脂饲料建立正常和不同阶段NAFLD兔模型。采用SWE测量肝脏弹性模量值(平均值、最小值、最大值),解剖取肝组织用于病理评估。光镜下判断肝纤维化程度,并根据NAFLD活动性评分(NAS),将兔分为正常组(NAS=0)、单纯性脂肪肝(SS)组(NAS=1,2)、交界组(NAS=3,4)、非酒精性脂肪性肝炎(NASH)组(NAS≥5)。采用Kruskal-Wallis检验评估NAFLD不同分组及肝纤维化不同分期间肝脏SWE弹性模量值的差异,并利用受试者操作特征(ROC)曲线评估SWE对不同程度NAFLD及肝纤维化的诊断效能。结果实验结束后共54只兔存活。其中,正常组11只、SS组8只、交界组19只、NASH组16只。肝纤维化分期中,S_0期32只、S_1期7只、S_2期9只、S_3期6只。以弹性模量平均值≥6.42 kPa诊断NAFLD,以弹性模量平均值≥8.64 kPa区分SS组与NASH组,ROC曲线下面积(AUC)分别为0.759、0.969,敏感度分别为60.5%、93.8%,特异度分别为100%、87.5%。以弹性模量平均值≥6.53 kPa、≥8.30 kPa、≥12.38 kPa分别诊断≥S_1期、≥S_2期、S_3期肝纤维化,AUC分别为0.910、0.961、0.974,敏感度分别为90.9%、100%、100%,特异度分别为84.4%、82.1%、89.6%。结论 SWE对评估NAFLD及含有NAFLD的肝纤维化程度具有一定价值。     

MR弹性成像与超声实时剪切波弹性成像评估兔肝纤维化的对比研究

目的比较MR弹性成像(MRE)与超声实时剪切波弹性成像(SWE)评估兔肝纤维化的价值。方法 2020年3月至11月间选取200只健康新西兰大白兔采用随机数表法随机分为对照组(40只)和肝纤维化组(160只)。将四氯化碳(CCl4)与橄榄油体积比为1∶1配成50%的CCl4油溶液, 肝纤维化组实验兔皮下注射50% CCl4油溶液。第1～3周每周注射1次, 剂量为0.1 ml/kg;第4～6周每周注射1次, 剂量为0.2 ml/kg;第7～16周每周注射2次, 剂量为0.1 ml/kg。对照组实验兔皮下注射等剂量生理盐水。肝纤维化组及对照组在第4、8、12、16周末采用随机数表法分别随机选取40、10只进行MRE和SWE检查, 分别获得肝脏弹性硬度值(LS), 记为LSMRE、LSSWE。检查结束后处死实验兔取肝组织进行病理学Scheuer纤维化分期, 分为F0～F4组。采用单因素方差分析评价不同肝纤维化分期间LSMRE、LSSWE的差异;LS值与病理分期的相关性分析采用Spearman法;采用受试者操作特征曲线评价LSMRE、LSSWE诊断肝纤维化分期的效能, 曲线下面积(AUC)的比较...     

MR弹性成像对肝纤维化的初步评价：参数测量的可重复性研究

目的:探讨磁共振弹性成像(MRE)评估慢性乙型肝炎患者纤维化程度的可重复性.方法:本院32例慢性乙型肝炎患者2次行肝脏常规MRI及MRE检查、且采用的MRE序列和扫描层面相同,所有患者在2个月内行肝脏穿刺活检证实有肝纤维化,其中轻度～中度纤维化(S1～S2)23例,中度～重度纤维化(S3～S4)9例.选择两次检查中对应的4个层面的解剖-弹性融合图,测量肝实质的弹性值.应用组内相关系数(ICC)及Bland-Altman方法评价两次扫描测量值的可重复性.采用Spearman检验分析患者肝纤维化分级与弹性值之间的相关性.结果:两次MRE检查中4个对应层面的肝脏平均弹性值的ICC值为0.923～0.956,肝脏最大弹性值的ICC值为0.761～0.893.轻度～中度纤维化患者两次检查测量的平均弹性值分别为(3.78±1.33)及(3.55±1.34)kPa,ICC值为0.909(95％CI:0.799～0.961);中度～重度纤维化患者两次检查测量的平均弹性值分别为(5.07±1.94)及(4.87±2.01)kPa,ICC值为0.941(95％CI:0.861～0.976).Bland-Altman方法显示不同层面测量的肝脏弹性值绝大多数位于95％置信区间内,提示可重复性良好.肝脏弹性值与肝纤维化程度呈显著正相关(P＜0.01).结论:应用MRE对慢性乙型肝炎纤维化患者进行肝脏硬度评价的过程中其重复性良好.     

磁共振弹性成像在家兔肝纤维化分期的实验研究

目的利用家兔肝纤维化模型评价磁共振弹性成像(MRE)在肝纤维化(HF)病理分期中的价值方法建立肝纤维化实验组(n=32)、实验补充组(n=12)、正常对照组(n=15)。对实验组及正常对照兔行常规MRI及MRE检查,测量肝实质的硬度(LS)值。HF组实验兔皮下注射50%CCl4后的第4、5、6、10周分别随机选择8只行MRI扫描。以肝脏纤维化病理组织学诊断为标准,评价第4、5、6、10周MRE与HF病理分期的相关性,并采用ROC曲线分析MRE的诊断准确性。结果不同分期HF的LS值之间存在显著差异(P<0.001),随着HF分期加重,LS值增加。LS与HF分期存在明显相关性(r=0.948,P<0.001)。LS区分各组别HF的敏感性、特异性、准确性、阳性预测值和阴性预测值分别为:≥S1期93.8%、93.3%、93.6%、96.8%、87.5%;≥S2期95.8%、95.7%、95.7%、95.8%、95.7%;≥S3期93.8%、96.8%、95.8%、93.8%、98.8%;S4期100%、97.4%、97.9%、100%、88.9%。结论 MRE作为一种安全、可靠地无创性HF分期技术,可为临床诊治、纵向研究提供一种重要的补充手段。     

MRI和CT细胞外容积对肝纤维化分期诊断价值的Meta分析

【摘要】目的:评价MR-T1-mapping成像和CT细胞外容积诊断肝纤维化的价值。方法:计算机检索PubMed、Cochrane library、Web of Science、中国知网、维普数据库和万方医学网，查找有关MR及CT的细胞外容积对肝纤维化的诊断性试验，检索时间截止2022年2月。由2位评价员按照纳入与排除标准独立筛选文献、提取资料和评价纳入研究的方法学质量后，采用Meta-Disc 1.4软件进行Meta分析。结果:最终纳入11篇文献，包括968例患者。以肝切除或组织活检病理、磁共振弹性成像（MRE）为金标准。基于MRI的ECV对明显肝纤维化(≥F2)组合并敏感度、特异度及SROC曲线下面积AUC值分别为0.74、0.83、0.9126，对严重肝纤维化(≥F3)组的敏感度、特异度分别为0.79、0.88，对早期肝硬化(F4)组的敏感度、特异度范围分别为0.85~0.87、0.80~0.87；基于CT碘值的ECV-iodine对≥F2、≥F3、F4组的合并敏感度和特异度分别为0.73和0.72、0.70和0.78、0.80和0.68，SROC曲线下面积分别为0.8023、0.8741、0.7465；基于常规CT绝对值的ECV-HU对≥F2、≥F3、F4组的合并敏感度和特异度分别为0.73和0.68、0.71和0.73、0.70和0.70，SROC曲线下面积分别为0.7612、0.7899、0.7680。结论:基于MRI的ECV诊断肝纤维化分期的准确性优于CT，而CT碘值所得ECV-iodine的诊断准确性优于常规CT值所得ECV-HU。     

双层探测器光谱CT诊断肝纤维化分期的最佳单能量研究北大核心CSCD

目的:探讨双层探测器光谱CT最佳单能量成像对肝纤维化的诊断价值。方法:采用CCl_(4)腹腔注射法诱导建立兔肝纤维化模型,分为实验组(n=26)和正常对照组(n=4)。在造模后采用双层探测器能谱CT进行双期增强扫描,测量混合能量(CPI)及单能量(VMI_(40~70 keV))肝脏标准化强化值(ΔCT)。根据METAVIR系统进行肝纤维化分期。采用Spearman相关性分析明确动脉期、门脉期的肝脏ΔCT_(CPI)及ΔCT_(VMI(40~70))与纤维化分期相关性;采用ROC曲线评价对纤维化分期的诊断效能。结果:动脉期ΔCT值与纤维化分期均无相关性,静脉期ΔCT_(CPI)及ΔCT_(VMI(40~70))值与纤维化分期呈不同程度正相关。ΔCT_(VMI 40)与纤维化分期的相关性最高(r=0.595,P=0.001),ΔCT_(CPI)与纤维化分期相关性最低(r=0.453,P=0.012)。ΔCT_(VMI 40)对≥F1、≥F2、≥F3和F4期纤维化的ROC曲线下面积分别为0.865、0.790、0.831和0.740。结论:双层探测器光谱CT最佳单能量成像所测定的肝脏强化值与纤维化相关性高于混合能量,提示其可以准确诊断各期肝纤维化。     

肝脏脂肪含量对超声瞬时弹性成像肝纤维化诊断效能的影响

目的 探讨肝脏脂肪含量对超声瞬时弹性成像(TE)肝纤维化分级诊断效能的影响。资料与方法 回顾性分析2017年1月—2020年7月在广州中医药大学第二临床医学院行肝脏穿刺的58例单纯慢性乙型肝炎(CHB)和58例CHB合并非酒精性脂肪肝(NAFLD)的影像学及病理资料,使用受试者工作特征曲线评估MRI质子密度脂肪分数(PDFF)和TE受控衰减参数(CAP)对肝脏脂肪含量的诊断效能,并使用Youden指数确定最佳截断值。以肝脏穿刺病理结果为“金标准”,探讨PDFF及CAP诊断的肝脏脂肪含量对TE肝脏硬度测量(LSM)诊断肝纤维化准确率的影响。结果 PDFF和CAP均能有效区分无-轻度与中-重度NAFLD,受试者工作特征曲线下面积分别为0.963、0.878,且PDFF优于CAP(Z=2.340,P=0.019);在经肝穿刺病理及PDFF诊断的中-重度NAFLD中,LSM对肝纤维化分级的诊断准确率明显低于无-轻度NAFLD(χ²=1.279,P=0.042;χ²=5.094,P=0.024)。PDFF区分无-轻度NAFLD与中-重度NAFLD的截断...     

3.0 T MR标准化表观扩散系数值评价肝纤维化程度的研究

目的 探讨标准化ADC值对肝纤维化程度定量分析的能力.方法 采用3.0 TMRDWI检查回顾性分析10名健康志愿者(对照组)和43例经肝脏穿刺活检病理证实为肝功能代偿期的肝病患者(慢性肝病组)资料,慢性肝病组患者进行肝纤维化分期(S分期).测量不同肝纤维化分期下肝脏ADC值、脾脏ADC值、肾皮质ADC值、脾脏标准化ADC值(S-ADC)及肾脏标准化ADC值(R-ADC).采用非参数Spearman检验分析S分期与ADC值之间的相关性;采用单因素方差分析比较各期ADC值间的差异,采用Logistic回归分析评价ADC值预测纤维化程度的能力,选择约登指数最大作为截断点,计算曲线下面积(AUC)、敏感度及特异度.结果 10名对照组志愿者均为SO期.慢性肝病组SO、S1、S2、S3、S4期分别有2、5、9、12和15例.S0～S4期肝脏ADC值分别为(1.37±0.13) ×10-3、(1.33±0.16)×10-3、(1.17±0.16) ×10 -3、(1.23 ±0.14)×10-3和(1.12 ±0.11)×10-3 mm2/s,S-ADC分别为1.86 ±0.18、1.68 ±0.12、1.34 ±0.14、1.48 ±0.15和1.34 ±0.10,R-ADC分别为0.71 ±0.08、0.68 0.12、0.61 ±0.09、0.64±0.11和0.60±0.08,差异均有统计学意义(F值分别为6.48、18.70和3.04,P＜0.05).S-ADC、肝脏ADC值和R-ADC均与肝纤维化分期呈负相关性(r值分别为-0.71、-0.51和-0.41,P值均＜0.01),但S-ADC与肝纤维化分期的相关性高于肝脏ADC值和R-ADC.对于预测≥S2期、≥S3期及s4期纤维化,S-ADC的效果均优于肝脏ADC值、R-ADC,约登指数分别为0.91、0.58和0.59.结论 S-ADC在评价肝纤维化方面优于肝脏ADC值及R-ADC,具有良好的诊断准确性.     

慢性肝病肝剪切波速与纤维化分级的相关性研究

目的: 探讨肝剪切波速与慢性肝病肝纤维化分级之间的关系.材料和方法: 以103例慢性肝病患者及26例健康人群为研究对象,利用声触诊组织量化技术分别定量测定肝脏的剪切波速;通过肝穿刺活检,以病理纤维化分级程度对研究对象进行分组,比较各纤维化分级与剪切波速之间的关系.结果: 103例肝病组患者中的94例进行肝穿刺活检;F0级的肝病患者与健康对照F0级之间剪切波速比较无显著性差异(P=0.058);除肝纤维化F0级与F1级、F3和F4级之间无显著性差异外,其余各组剪切波速均值之间(F0与F2、F3、F4之间,F1与F2、F3、F4之间,F2与F3、F4之间)的比较都有显著性差异(P＜0.05); 诊断肝纤维化F≥1、F≥2、F≥3 和 F=4分别对应的ROC曲线下面积分别为0.834、0.958、0.966、0.895,对应的肝脏剪切波速临界阈值分别为1.42m/s、1.60m/s、2.19m/s、2.41m/s,对应的诊断敏感性分别为72.0% 、93.2% 、96.3% 、93.9%;特异性分别为82.1%、86.4%、88.2%、81.9%.结论: 肝纤维化是影响肝脏剪切波速的主要因素;肝脏剪切波速随纤维化分级的增高而增快,是判断慢性肝病肝脏纤维化程度及分级的可靠指标.     

1H-MRS和CT在非酒精性脂肪肝诊疗中的应用研究

目的:应用磁共振质子波谱成像(1H-MRS)技术和CT定量诊断非酒精性脂肪肝(NAFLD)及评价药物疗效.方法:依中华医学会NAFLD诊断标准入选NAFLD患者22例,并与20例健康组对照.两组均行肝脏1H MRS扫描和CT平扫,计算肝内脂质含量(IHCL)和CT肝/脾比值.NAFLD组患者服用肝脂消胶囊8周,检测治疗前后IHCL和CT肝/脾比值的变化.结果:NAFLD组IHCL较正常组明显升高,CT肝/脾比值较正常组明显下降.经治疗后IHCL明显下降,CT肝/脾比值明显升高.结论:肝脏1H-MRS扫描可对肝脏内脂质含量进行准确定量,优于CT平扫.     

Diagnostic Performance of Spin-Echo Echo-Planar Imaging Magnetic Resonance Elastography in 3T System for Noninvasive Assessment of Hepatic Fibrosis

ObjectiveTo validate the performance of 3T spin-echo echo-planar imaging (SE-EPI) magnetic resonance elastography (MRE) for staging hepatic fibrosis in a large population, using surgical specimens as the reference standard.Materials and MethodsThis retrospective study initially included 310 adults (155 undergoing hepatic resection and 155 undergoing donor hepatectomy) with histopathologic results from surgical liver specimens. They underwent 3T SE-EPI MRE ≤ 3 months prior to surgery. Demographic findings, underlying liver disease, and hepatic fibrosis pathologic stage according to METAVIR were recorded. Liver stiffness (LS) was measured by two radiologists, and inter-reader reproducibility was evaluated using the intraclass correlation coefficient (ICC). The mean LS of each fibrosis stage (F0–F4) was calculated in total and for each etiologic subgroup. Comparisons among subgroups were performed using the Kruskal–Wallis test and Conover post-hoc test. The cutoff values for fibrosis staging were estimated using receiver operating characteristic (ROC) curve analysis.ResultsInter-reader reproducibility was excellent (ICC, 0.98; 95% confidence interval, 0.97–0.99). The mean LS values were 1.91, 2.41, 3.24, and 5.41 kPa in F0–F1 (n = 171), F2 (n = 26), F3 (n = 38), and F4 (n = 72), respectively. The discriminating cutoff values for diagnosing ≥ F2, ≥ F3, and F4 were 2.18, 2.71, and 3.15 kPa, respectively, with the ROC curve areas of 0.97–0.98 (sensitivity 91.2%–95.9%, specificity 90.7%–99.0%). The mean LS was significantly higher in patients with cirrhosis (F4) of nonviral causes, such as primary biliary cirrhosis (9.56 kPa) and alcoholic liver disease (7.17 kPa) than in those with hepatitis B or C cirrhosis (4.28 and 4.92 kPa, respectively). There were no statistically significant differences in LS among the different etiologic subgroups in the F0–F3 stages.ConclusionThe 3T SE-EPI MRE demonstrated high interobserver reproducibility, and our criteria for staging hepatic fibrosis showed high diagnostic performance. LS was significantly higher in patients with non-viral cirrhosis than in those with viral cirrhosis.     

Noninvasive Assessment of Hepatic Fibrosis in Patients with Chronic Hepatitis B Viral Infection Using Magnetic Resonance Elastography

Objective

To evaluate the diagnostic performance of magnetic resonance elastography (MRE) for staging hepatic fibrosis in patients with chronic hepatitis B virus (HBV) infection.

Materials and Methods

Patients with chronic HBV infection who were suspected of having focal or diffuse liver diseases (n = 195) and living donor candidates (n = 166) underwent MRE as part of the routine liver MRI examination. We measured liver stiffness (LS) values on quantitative shear stiffness maps. The technical success rate of MRE was then determined. Liver cell necroinflammatory activity and fibrosis were assessed using histopathologic examinations as the reference. Areas under the receiver operating characteristic curve (Az) were calculated in order to predict the liver fibrosis stage.

Results

The technical success rate of MRE was 92.5% (334/361). The causes of technical failure were poor wave propagation (n = 12), severe respiratory motion (n = 3), or the presence of iron deposits in the liver (n = 12). The mean LS values, as measured by MRE, increased significantly along with an increase in the fibrosis stage (r = 0.901, p < 0.001); however, the mean LS values did not increase significantly along with the degree of necroinflammatory activity. The cutoff values of LS for ≥ F1, ≥ F2, ≥ F3, and F4 were 2.45 kPa, 2.69 kPa, 3.0 kPa, and 3.94 kPa, respectively, and with Az values of 0.987-0.988.

Conclusion

MRE has a high technical success rate and excellent diagnostic accuracy for staging hepatic fibrosis in patients with chronic HBV infection.     

MR elastography for noninvasive assessment of hepatic fibrosis: experience from a tertiary center in Asia

Purpose:

To determine the sensitivity and specificity of MR elastography (MRE) in the staging of hepatic fibrosis (HF) using histopathology as the reference standard in an Asian population.

Materials and Methods:

MRE was performed on 55 patients with chronic liver diseases or biliary diseases and on 5 living related liver donors (48 men and 12 women; mean age, 55.7 years). MRE was performed with modified, phase‐contrast, gradient‐echo sequences, and the mean stiffness values were measured on the elastograms in kilopascals(kPa). Receiver operating characteristic curve analysis was performed to determine the cutoff value and accuracy of MRE for staging HF. Histopathologic staging of HF according to the METAVIR scoring system served as the reference.

Results:

Liver stiffness increased systematically along with the fibrosis stage. With a shear stiffness cutoff value of 3.05 kPa, the predicted sensitivity and specificity for differentiating significant liver fibrosis (≥ F2) from mild fibrosis (F1) were 89.7% and 87.1%, respectively. In addition, MRE was able to discriminate between patients with severe fibrosis (F3) and those with liver cirrhosis (sensitivity, 100%; specificity, 92.2%), with a shear stiffness cutoff value of 5.32 kPa.

Conclusion:

MRE could be a promising, noninvasive technique with excellent diagnostic accuracy for detecting significant HF and liver cirrhosis. J. Magn. Reson. Imaging 2011. © 2011 Wiley Periodicals, Inc.     

实时剪切波弹性成像诊断急性肝创伤的动物实验研究

目的 探讨实时剪切波弹性成像(SWE)在急性肝创伤中的诊断价值.材料与方法 16只健康新西兰兔,用止血钳制作开放性肝创伤模型,每只实验兔选2个肝叶制作2个创伤灶,共成功建立30个创伤模型,以正常30例肝组织为对照,采用自身对照方法使用SuperSonic Imagine AixPlorer实时剪切波弹性成像仪测量正常肝组织及创伤灶的弹性值,应用接受者操作特性曲线(ROC曲线)进行分析,超声造影确定创伤灶.结果 成功建立开放性肝创伤灶30处.肝创伤灶的弹性最大值、平均值及最小值分别为(17.20±4.30)kPa、(11.06±1.33) kPa、(8.34±1.80) kPa;正常肝组织的弹性最大值、平均值及最小值分别为(10.68±1.89) kPa、( 8.26±1.01) kPa、(6.51±0.77) kPa,两组比较,差异均有统计学意义(P＜0.05).肝创伤灶弹性最大值为12.44kPa时诊断敏感度为96.7％,特异度为83.3％;平均值为10.05kPa时诊断敏感度为90.0％,特异度为96.7％;最小值为7.23kPa时诊断敏感度为70.0％,特异度为86.7％.结论 肝创伤灶弹性最大值、平均值和最小值均与正常肝组织不同,实时剪切波弹性成像为诊断急性肝创伤提供了可供选择的方法.     

Magnetresonanzelastographie der Leber

CLINICAL/METHODICAL ISSUE: The early detection of liver fibrosis remains a major challenge in medical imaging. STANDARD RADIOLOGICAL METHODS: Nowadays staging of liver fibrosis is not a task for radiological examinations and the gold standard is liver puncture. METHODICAL INNOVATIONS: Elastography is sensitive to the mechanical properties of soft tissues and in the liver stiffness is highly correlated to the degree of fibrosis. In magnetic resonance imaging elastography (MRE) time-harmonic vibrations are induced in the liver and encoded by motion-sensitive phase-contrast sequences. Viscoelastic constants are recovered from the obtained wave images and displayed by so-called elastograms. PERFORMANCE: The MRE procedure is able to discriminate low grades of fibrosis (F0-F1) from medium and severe fibrosis (F2-F4) with a diagnostic accuracy (AUROC) of 0.92. ACHIEVEMENTS: Currently, MRE is the most sensitive imaging modality for the noninvasive staging of liver fibrosis. PRACTICAL RECOMMENDATIONS: Current technical developments of MRE may further improve the accuracy of the method towards a new gold standard for noninvasive staging of fibrosis by radiologists.     

Two-Dimensional Shear Wave Elastography Predicts Liver Fibrosis in Jaundiced Infants with Suspected Biliary Atresia: A Prospective Study

ObjectiveThis study aimed to evaluate the role of preoperative two-dimensional (2D) shear wave elastography (SWE) in assessing the stages of liver fibrosis in patients with suspected biliary atresia (BA) and compared its diagnostic performance with those of serum fibrosis biomarkers.Materials and MethodsThis study was approved by the ethical committee, and written informed parental consent was obtained. Two hundred and sixteen patients were prospectively enrolled between January 2012 and October 2018. The 2D SWE measurements of 69 patients have been previously reported. 2D SWE measurements, serum fibrosis biomarkers, including fibrotic markers and biochemical test results, and liver histology parameters were obtained. 2D SWE values, serum biomarkers including, aspartate aminotransferase to platelet ratio index (APRi), and other serum fibrotic markers were correlated with the stages of liver fibrosis by METAVIR. Receiver operating characteristic (ROC) curves and area under the ROC (AUROC) curve analyses were used.ResultsThe correlation coefficient of 2D SWE value in correlation with the stages of liver fibrosis was 0.789 (p < 0.001). The cut-off values of 2D SWE were calculated as 9.1 kPa for F1, 11.6 kPa for F2, 13.0 kPa for F3, and 15.7 kPa for F4. The AUROCs of 2D SWE in the determination of the stages of liver fibrosis ranged from 0.869 to 0.941. The sensitivity and negative predictive value of 2D SWE in the diagnosis of ≥ F3 was 93.4% and 96.0%, respectively. The diagnostic performance of 2D SWE was superior to that of APRi and other serum fibrotic markers in predicting severe fibrosis and cirrhosis (all p < 0.005) and other serum biomarkers. Multivariate analysis showed that the 2D SWE value was the only statistically significant parameter for predicting liver fibrosis.Conclusion2D SWE is a more effective non-invasive tool for predicting the stage of liver fibrosis in patients with suspected BA, compared with serum fibrosis biomarkers.     

Liver fibrosis: noninvasive assessment with MR elastography versus aspartate aminotransferase-to-platelet ratio index

PURPOSE: To prospectively compare the sensitivity and specificity of magnetic resonance (MR) elastography with those of the routinely available aspartate aminotransferase-to-platelet ratio index (APRI) test for staging hepatic fibrosis in patients who have undergone liver biopsy for suspicion of chronic liver disease, with histopathologic examination as the reference standard. MATERIALS AND METHODS: The study was approved by the ethics committee. All patients gave written informed consent. Eighty-eight patients (37 men, 51 women; mean age, 54.0 years +/- 13.1 [standard deviation]) who underwent liver biopsy for suspicion of chronic liver disease underwent MR elastography and APRI testing within 2 days after liver biopsy. At histopathologic examination, the fibrosis stage was assessed according to METAVIR scores (fibrosis scores F0 [no fibrosis] to F4 [cirrhosis]). MR elastography was performed by transmitting mechanical waves within the liver and measuring the small cyclic displacement of the liver spins with a phase-contrast spin-echo sequence. The performances of MR elastography and APRI testing were assessed, and the optimal cutoff values for fibrosis stage were determined with receiver operating characteristic (ROC) curve analysis. RESULTS: At MR elastography, areas under the ROC curves (A(z)) for elasticity and viscosity, respectively, were 0.999 and 0.863 at fibrosis scores greater than or equal to F2, 0.997 and 0.962 at scores greater than or equal to F3, and 1.000 and 0.986 at score F4. A(z) values for elasticity at MR were significantly larger than those for the APRI (0.854 at scores > or = F2, P < .001; 0.886 at scores > or = F3, P = .003; and 0.851 at score F4, P = .004). Optimal cutoff values of elasticity were 2.5 kPa for fibrosis scores greater than or equal to F2, 3.1 kPa for scores greater than or equal to F3, and 4.3 kPa for score F4. CONCLUSION: Large A(z) values for elasticity (>0.990 for scores > or = F2, > or = F3, and F4) show that MR elastography was accurate in liver fibrosis staging and superior to biochemical testing with APRIs.     

肝脏实时剪切波弹性成像和超声量化评分评价恩替卡韦治疗慢性乙型肝炎肝纤维化疗效的研究

目的评价恩替卡韦治疗慢性乙型肝炎肝纤维化的疗效,并使用肝脏实时剪切波弹性成像和超声量化评分对疗效进行对比分析。方法选择在2017年10月至2018年3月本院收治的54例慢性乙型肝炎肝纤维化患者,对其进行肝脏实时剪切波弹性成像和超声量化检查,之后对患者实施恩替卡韦治疗,治疗周期为1年,治疗后再次实施肝脏实时剪切波弹性成像和超声量检查,对2次检查的各项指标进行对比,分析检查指标的差异。结果治疗前S1-S3期与S4期超声评分、肝硬度进行对比,差异有统计学意义,治疗后患者超声评分、肝硬度(kPa)指标低于治疗前(P<0.05)。结论恩替卡韦治疗慢性乙型肝炎肝纤维化疗效较为显著,同时在进行病情评估的过程中实施肝脏实时剪切波弹性成像和超声量化评分,可以对肝脏疾病的不同阶段进行分期,检查和治疗的效果均较为理想。     

Non-invasive evaluation of liver fibrosis: a comparison of ultrasound-based transient elastography and MR elastography in patients with viral hepatitis B and C

Objective

To compare the diagnostic accuracy of TE and MRE and establish cutoff levels and diagnostic strategies for both techniques, enabling selection of patients for liver biopsy.

Methods

One hundred three patients with chronic hepatitis B or C and liver biopsy were prospectively included. Areas under curves (AUROC) were compared for TE and MRE for METAVIR fibrosis grade?≥?F2 and ≥F3. We defined cutoff values for selection of patients with F0–F1 (sensitivity >95 %) and for significant fibrosis F2–F4 (specificity >95 %).

Results

Following exclusions, 85 patients were analysed (65 CHB, 19 CHC, 1 co-infected). Fibrosis stages were F0 (n?=?3), F1 (n?=?53), F2 (n?=?15), F3 (n?=?8) and F4 (n?=?6). TE and MRE accuracy were comparable [AUROC_TE?≥?F2: 0.914 (95 % CI: 0.857–0.972) vs. AUROC_MRE?≥?F2: 0.909 (0.840–0.977), P?=?0.89; AUROC_TE?≥?F3: 0.895 (0.816–0.974) vs. AUROC_MRE?≥?F3: 0.928 (0.874–0.982), P?=?0.42]. Cutoff values of <5.2 and ≥8.9 kPa (TE) and <1.66 and ≥2.18 kPa (MRE) diagnosed 64 % and 66 % of patients correctly as F0–F1 or F2–F4. A conditional strategy in inconclusive test results increased diagnostic yield to 80 %.

Conclusion

TE and MRE have comparable accuracy for detecting significant fibrosis, which was reliably detected or excluded in two-thirds of patients. A conditional strategy further increased diagnostic yield to 80 %.

Key Points

? Both ultrasound-based transient elastography and magnetic resonance elastography can assess hepatic fibrosis. ? Both have comparable accuracy for detecting liver fibrosis in viral hepatitis. ? The individual techniques reliably detect or exclude significant liver fibrosis in 66 %. ? A conditional strategy for inconclusive findings increases the number of correct diagnoses.     

Accuracy of MR elastography and anatomic MR imaging features in the diagnosis of severe hepatic fibrosis and cirrhosis

Purpose:

To compare the diagnostic accuracy of magnetic resonance imaging elastography (MRE) and anatomic MRI features in the diagnosis of severe hepatic fibrosis and cirrhosis.

Materials and Methods:

Three readers independently assessed presence of morphological changes associated with hepatic fibrosis in 72 patients with liver biopsy including: caudate to right lobe ratios, nodularity, portal venous hypertension (PVH) stigmata, posterior hepatic notch, expanded gallbladder fossa, and right hepatic vein caliber. Three readers measured shear stiffness values using quantitative shear stiffness maps (elastograms). Sensitivity, specificity, and diagnostic accuracy of stiffness values and each morphological feature were calculated. Interreader agreement was summarized using weighted kappa statistics. Intraclass correlation coefficient was used to assess interreader reproducibility of stiffness measurements. Binary logistic regression was used to assess interreader variability for dichotomized stiffness values and each morphological feature.

Results:

Using 5.9 kPa as a cutoff for differentiating F3‐F4 from F0‐2 stages, overall sensitivity, specificity, and diagnostic accuracy for MRE were 85.4%, 88.4%, and 87%, respectively. Overall interreader agreement for stiffness values was substantial, with an insignificant difference (P = 0.74) in the frequency of differentiating F3‐4 from F0‐2 fibrosis. Only hepatic nodularity and PVH stigmata showed moderately high overall accuracy of 69.4% and 72.2%. Interreader agreement was substantial only for PVH stigmata, moderate for C/R m, deep notch, and expanded gallbladder fossa. Only posterior hepatic notch (P = 0.82) showed no significant difference in reader rating.

Conclusion:

MRE is a noninvasive, accurate, and reproducible technique compared with conventional features of detecting severe hepatic fibrosis. J. Magn. Reson. Imaging 2012;35:1356–1364. © 2012 Wiley Periodicals, Inc.