Amorim Viviane Brandão, Parente Daniella Braz, Paiva Fernando Fernandes, Oliveira Neto Jaime Araújo, Miranda Amanda Almeida, Moreira Cláudia Cravo, Fernandes Flávia Ferreira, Campos Carlos Frederico Ferreira, Leite Nathalie Carvalho, Perez Renata de Mello, Rodrigues Rosana Souza
Research Department, D'Or Institute for Research and Education, Rio de Janeiro 22281, Brazil.
São Carlos Institute of Physics, University of São Paulo, São Carlos 13560-970, Brazil.
World J Hepatol. 2020 Sep 27;12(9):661-671. doi: 10.4254/wjh.v12.i9.661.
Nonalcoholic fatty liver disease (NAFLD) is a major cause of liver disease worldwide. The diagnosis of nonalcoholic steatohepatitis (NASH), the most severe form of NAFLD, is crucial and has prognostic and therapeutic implications. However, currently this diagnosis is based on liver biopsy and has several limitations.
To evaluate the performance of gadoxetic acid-enhanced magnetic resonance imaging (GA-MRI) in differentiating isolated steatosis from NASH in patients with NAFLD.
In this prospective study, 56 patients with NAFLD (18 with isolated steatosis and 38 with NASH) underwent GA-MRI. The contrast enhancement index (CEI) was calculated as the rate of increase of the liver-to-muscle signal intensity ratio from before and 20 min after intravenous GA administration. Between-group differences in mean CEI were examined using Student's test. The area under the receiver operator characteristic curve and the diagnostic performance of gadoxetic acid-enhanced magnetic resonance imaging were evaluated.
The mean CEI for all subjects was 1.82 ± 0.19. The mean CEI was significantly lower in patients with NASH than in those with isolated steatosis ( = 0.008). Two CEI cut-off points were used: < 1.66 (94% specificity) to characterize NASH and > 2.00 (89% sensitivity) to characterize isolated steatosis. CEI values between 1.66 and 2.00 indicated liver biopsy, and the procedure could be avoided in 40% of patients with NAFLD.
GA-MRI is an effective noninvasive method that may be useful for the differentiation of NASH from isolated steatosis, and could help to avoid liver biopsy in patients with NAFLD.
非酒精性脂肪性肝病（NAFLD）是全球肝脏疾病的主要病因。非酒精性脂肪性肝炎（NASH）是NAFLD最严重的形式，其诊断至关重要，具有预后和治疗意义。然而，目前该诊断基于肝活检，存在一些局限性。
评估钆塞酸增强磁共振成像（GA-MRI）在区分NAFLD患者单纯性脂肪变性与NASH方面的性能。
在这项前瞻性研究中，56例NAFLD患者（18例单纯性脂肪变性和38例NASH）接受了GA-MRI检查。对比增强指数（CEI）计算为静脉注射GA前和注射后20分钟肝脏与肌肉信号强度比值的增加率。使用Student's检验检查组间平均CEI的差异。评估了受试者操作特征曲线下面积和钆塞酸增强磁共振成像的诊断性能。
所有受试者的平均CEI为1.82±0.19。NASH患者的平均CEI显著低于单纯性脂肪变性患者（P = 0.008）。使用了两个CEI截断点：<1.66（特异性94%）来表征NASH，>2.00（敏感性89%）来表征单纯性脂肪变性。CEI值在1.66和2.00之间表明需要进行肝活检，40%的NAFLD患者可以避免该操作。
GA-MRI是一种有效的非侵入性方法，可能有助于区分NASH与单纯性脂肪变性，并有助于避免NAFLD患者进行肝活检。
