MRI对非酒精性脂肪性肝病定量评估研究进展

Progress in MRI evaluation of nonalcoholic fatty liver disease

非酒精性脂肪性肝病(non-alcoholic fatty liver disease,NAFLD)是慢性肝病的常见原因。NAFLD主要分为非酒精性脂肪肝(non-alcoholic fatty liver,NAFL)和非酒精性脂肪性肝炎(non-alcoholic steatohepatitis,NASH)两种亚型。NASH是NAFLD的进展形式,可进一步促进肝纤维化并增加发生肝硬化的风险。因此,准确地区分出NAFL和NASH以及评估肝脏炎症和纤维化程度对于预防疾病的进展和不良后果至关重要。MRI检查是一种非侵入性的肝脏评估方法,可以提供肝脏解剖学、功能及代谢信息,对于NAFLD的诊断和分期具有重要价值。本文主要介绍了磁共振质子密度脂肪分数(magnetic resonance imaging proton density fat fraction,MRI-PDFF)、纵向弛豫时间定量成像(T1 mapping)及磁共振弹性成像(magnetic resonance elastography,MRE)的技术原理并总结了这三种定量成像技术在NAFLD评估中的研究现状,旨在讨论MR定量成像技术在NAFLD评估中的优势及面临的一些挑战,为MR量化NAFLD病理改变提供新的研究思路。

Non-alcoholic fatty liver disease(NAFLD)is a common cause of chronic liver disease.NAFLD is divided into two main subtypes,non-alcoholic fatty liver(NAFL)and non-alcoholic steatohepatitis(NASH).NASH is a progressive form of NAFLD that can further promote liver fibrosis and increase the risk of developing cirrhosis,so accurately distinguishing between nonalcoholic fatty liver disease and NASH and assessing the extent of liver inflammation and fibrosis is critical to prevent progression and adverse outcomes of the disease.MRI is a non-invasive method of liver evaluation,which can provide anatomical,functional and metabolic information of the liver,and is of great value in the diagnosis and staging of NAFLD.This review introduces the technical principles of magnetic resonance imaging proton density fat fraction(MRI-PDFF),magnetic resonance elastography(MRE)and longitudinal relaxation time quantitative imaging(T1 mapping),and summarizes the research status of these quantitative imaging techniques in the evaluation of NAFLD.This review aims to discuss the advantages and challenges of MR quantitative imaging in the assessment of NAFLD,and provide new research ideas for quantifying the pathological changes of NAFLD.