Lv Shujing, Jiang Sushan, Liu Shousheng, Dong Quanjiang, Xin Yongning, Xuan Shiying
Medical College of Qingdao University, Qingdao, Shandong, China.
Digestive Disease Key Laboratory of Qingdao, Qingdao, Shandong, China.
J Clin Transl Hepatol. 2018 Jun 28;6(2):217-221. doi: 10.14218/JCTH.2018.00021. Epub 2018 Jun 22.
Nonalcoholic fatty liver disease (NAFLD) ranges from simple steatosis to NAFLD-related liver cirrhosis and is a main cause of chronic liver diseases. Patients with nonalcoholic steatohepatitis and fibrosis are at a great risk of the progression to cirrhosis or hepatocellular carcinoma, both of which are tightly associated with liver-related mortality. Liver biopsy is still the gold standard for the diagnosis of NAFLD, but some defects, such as serious complications, sampling error and variability in histologic evaluation among pathologists, remain problematic. Therefore, noninvasive, repeatable and accurate diagnostic methods are urgently needed. Ultrasonography is a well-established and lower-cost imaging technique for the diagnosis of hepatic steatosis, especially suitable for population census, but limited by its low sensitivity to diagnose mild steatosis and being highly operator-dependent. Computed tomography also lacks the sensitivity to detect mild steatosis and small changes in fat content, and presents a potential radiation hazard. Controlled attenuation parameter based on the FibroScan technology is a promising tool for noninvasive semiquantitative assessment of liver fat content, but the accuracy rate depends on the operator's expertise and is affected by age, width of the intercostal space, skin capsular distance and body mass index. Magnetic resonance imaging and magnetic resonance spectroscopy are regarded as the most accurate quantitative methods for measuring liver fat content in clinical practice, especially for longitudinal follow up of NAFLD patients. In this review, we mainly introduce the current imaging methods that are in use for evaluation of liver fat content and we discuss the advantages and disadvantages of each method.
非酒精性脂肪性肝病（NAFLD）范围从单纯性脂肪变性到与NAFLD相关的肝硬化，是慢性肝病的主要原因。非酒精性脂肪性肝炎和纤维化患者进展为肝硬化或肝细胞癌的风险很大，这两者均与肝脏相关死亡率密切相关。肝活检仍是诊断NAFLD的金标准，但一些缺陷，如严重并发症、抽样误差以及病理学家之间组织学评估的变异性，仍然存在问题。因此，迫切需要无创、可重复且准确的诊断方法。超声检查是一种成熟且成本较低的用于诊断肝脂肪变性的成像技术，特别适用于人群普查，但受其对轻度脂肪变性诊断敏感性低以及高度依赖操作者的限制。计算机断层扫描也缺乏检测轻度脂肪变性和脂肪含量微小变化的敏感性，并且存在潜在的辐射危害。基于FibroScan技术的受控衰减参数是用于肝脂肪含量无创半定量评估的一种有前景的工具，但准确率取决于操作者的专业知识，并且受年龄、肋间间隙宽度、皮肤包膜距离和体重指数的影响。磁共振成像和磁共振波谱在临床实践中被视为测量肝脂肪含量最准确的定量方法，尤其是用于NAFLD患者的纵向随访。在本综述中，我们主要介绍目前用于评估肝脂肪含量的成像方法，并讨论每种方法的优缺点。
