Karlas Thomas, Petroff David, Garnov Nikita, Böhm Stephan, Tenckhoff Hannelore, Wittekind Christian, Wiese Manfred, Schiefke Ingolf, Linder Nicolas, Schaudinn Alexander, Busse Harald, Kahn Thomas, Mössner Joachim, Berg Thomas, Tröltzsch Michael, Keim Volker, Wiegand Johannes
IFB AdiposityDiseases, Leipzig University Medical Center, Leipzig, Germany; Department of Medicine, Neurology and Dermatology, Division of Gastroenterology and Rheumatology, University Hospital Leipzig, Leipzig, Germany.
IFB AdiposityDiseases, Leipzig University Medical Center, Leipzig, Germany; Clinical Trial Center, University of Leipzig, Leipzig, Germany.
PLoS One. 2014 Mar 17;9(3):e91987. doi: 10.1371/journal.pone.0091987. eCollection 2014.
Non-invasive assessment of steatosis and fibrosis is of growing relevance in non-alcoholic fatty liver disease (NAFLD). 1H-Magnetic resonance spectroscopy (1H-MRS) and the ultrasound-based controlled attenuation parameter (CAP) correlate with biopsy proven steatosis, but have not been correlated with each other so far. We therefore performed a head-to-head comparison between both methods.
Fifty patients with biopsy-proven NAFLD and 15 healthy volunteers were evaluated with 1H-MRS and transient elastography (TE) including CAP. Steatosis was defined according to the percentage of affected hepatocytes: S1 5-33%, S2 34-66%, S3 ≥67%.
Steatosis grade in patients with NAFLD was S1 36%, S2 40% and S3 24%. CAP and 1H-MRS significantly correlated with histopathology and showed comparable accuracy for the detection of hepatic steatosis: areas under the receiver-operating characteristics curves were 0.93 vs. 0.88 for steatosis ≥S1 and 0.94 vs. 0.88 for ≥S2, respectively. Boot-strapping analysis revealed a CAP cut-off of 300 dB/m for detection of S2-3 steatosis, while retaining the lower cut-off of 215 dB/m for the definition of healthy individuals. Direct comparison between CAP and 1H-MRS revealed only modest correlation (total cohort: r = 0.63 [0.44, 0.76]; NAFLD cases: r = 0.56 [0.32, 0.74]). For detection of F2-4 fibrosis TE had sensitivity and specificity of 100% and 98.1% at a cut-off value of 8.85 kPa.
Our data suggest a comparable diagnostic value of CAP and 1H-MRS for hepatic steatosis quantification. Combined with the simultaneous TE fibrosis assessment, CAP represents an efficient method for non-invasive characterization of NAFLD. Limited correlation between CAP and 1H-MRS may be explained by different technical aspects, anthropometry, and presence of advanced liver fibrosis.
在非酒精性脂肪性肝病（NAFLD）中，对脂肪变性和纤维化进行无创评估的相关性日益增加。氢质子磁共振波谱（1H-MRS）和基于超声的受控衰减参数（CAP）与经活检证实的脂肪变性相关，但到目前为止两者尚未相互关联。因此，我们对这两种方法进行了直接比较。
对50例经活检证实为NAFLD的患者和15名健康志愿者进行了1H-MRS和包括CAP的瞬时弹性成像（TE）评估。根据受影响肝细胞的百分比定义脂肪变性：S1为5%-33%，S2为34%-66%，S3≥67%。
NAFLD患者的脂肪变性分级为S1占36%，S2占40%，S3占24%。CAP和1H-MRS与组织病理学显著相关，并且在检测肝脂肪变性方面显示出相当的准确性：对于脂肪变性≥S1，受试者操作特征曲线下面积分别为0.93和0.88；对于≥S2，分别为0.94和0.88。自举分析显示，检测S2-3脂肪变性的CAP临界值为300 dB/m，而对于健康个体的定义，保留较低的临界值215 dB/m。CAP和1H-MRS之间的直接比较仅显示出适度的相关性（总队列：r = 0.63 [0.44, 0.76]；NAFLD病例：r = 0.56 [0.32, 0.74]）。对于检测F2-4纤维化，TE在临界值8.85 kPa时的敏感性和特异性分别为100%和98.1%。
我们的数据表明，CAP和1H-MRS在肝脂肪变性定量方面具有相当的诊断价值。结合同时进行的TE纤维化评估，CAP是一种对NAFLD进行无创特征描述的有效方法。CAP和1H-MRS之间有限的相关性可能由不同的技术方面、人体测量学以及晚期肝纤维化的存在来解释。
