Lee Seung Soo, Park Seong Ho
Seung Soo Lee, Seong Ho Park, Department of Radiology and Research Institute of Radiology, University of Ulsan College of Medicine, Asan Medical Center, Seoul 138-736, South Korea.
World J Gastroenterol. 2014 Jun 21;20(23):7392-402. doi: 10.3748/wjg.v20.i23.7392.
Nonalcoholic fatty liver disease (NAFLD) is a frequent cause of chronic liver diseases, ranging from simple steatosis to nonalcoholic steatohepatitis (NASH)-related liver cirrhosis. Although liver biopsy is still the gold standard for the diagnosis of NAFLD, especially for the diagnosis of NASH, imaging methods have been increasingly accepted as noninvasive alternatives to liver biopsy. Ultrasonography is a well-established and cost-effective imaging technique for the diagnosis of hepatic steatosis, especially for screening a large population at risk of NAFLD. Ultrasonography has a reasonable accuracy in detecting moderate-to-severe hepatic steatosis although it is less accurate for detecting mild hepatic steatosis, operator-dependent, and rather qualitative. Computed tomography is not appropriate for general population assessment of hepatic steatosis given its inaccuracy in detecting mild hepatic steatosis and potential radiation hazard. However, computed tomography may be effective in specific clinical situations, such as evaluation of donor candidates for hepatic transplantation. Magnetic resonance spectroscopy and magnetic resonance imaging are now regarded as the most accurate practical methods of measuring liver fat in clinical practice, especially for longitudinal follow-up of patients with NAFLD. Ultrasound elastography and magnetic resonance elastography are increasingly used to evaluate the degree of liver fibrosis in patients with NAFLD and to differentiate NASH from simple steatosis. This article will review current imaging methods used to evaluate hepatic steatosis, including the diagnostic accuracy, limitations, and practical applicability of each method. It will also briefly describe the potential role of elastography techniques in the evaluation of patients with NAFLD.
非酒精性脂肪性肝病（NAFLD）是慢性肝病的常见病因，范围从单纯性脂肪变性到非酒精性脂肪性肝炎（NASH）相关的肝硬化。尽管肝活检仍是诊断NAFLD的金标准，尤其是诊断NASH，但成像方法已越来越多地被接受为肝活检的非侵入性替代方法。超声检查是一种成熟且经济高效的成像技术，用于诊断肝脂肪变性，特别是用于筛查大量有NAFLD风险的人群。超声检查在检测中重度肝脂肪变性方面具有合理的准确性，尽管其在检测轻度肝脂肪变性方面准确性较低，依赖操作者，且较为定性。计算机断层扫描不适用于对一般人群进行肝脂肪变性评估，因为其在检测轻度肝脂肪变性方面不准确且存在潜在辐射危害。然而，计算机断层扫描在特定临床情况下可能有效，例如评估肝移植供体候选人。磁共振波谱和磁共振成像现在被认为是临床实践中测量肝脏脂肪最准确的实用方法，尤其是对于NAFLD患者的纵向随访。超声弹性成像和磁共振弹性成像越来越多地用于评估NAFLD患者的肝纤维化程度，并区分NASH和单纯性脂肪变性。本文将综述目前用于评估肝脂肪变性的成像方法，包括每种方法的诊断准确性、局限性和实际适用性。还将简要描述弹性成像技术在评估NAFLD患者中的潜在作用。
