MR spectroscopy, Department of Diagnostic and Interventional Radiology, Institute for Clinical and Experimental Medicine, 140 21, Prague 4, Czech Republic.
MAGMA. 2011 Oct;24(5):297-304. doi: 10.1007/s10334-011-0264-9. Epub 2011 Jul 10.
Among several non-invasive methods of liver fat analysis, the most important role is played by MR imaging and spectroscopy (MRS). This study describes the 1H MRS at 3T measurement of liver fat volume fraction Φ(fat) in a group of liver transplant patients, an at-risk group for the development of de novo steatosis.
Seventy-seven liver transplant recipients who underwent routine protocolar posttransplant examination were divided into three groups: CON-PAT (control group for the cross validation test, 48 patients), PAT-PAT (patients test group for the cross validation test, 29 patients), and PAT (pooled data). Single voxel 1H MRS at 3T was used for the determination of Φ(fat) and histology results (His) were used as the reference standard.
Linear and non-linear regression models were used to describe the relationship between Φ(fat) and His. Strong correlation was found for both models with r = 0.83-0.94 (P < 0.001); a higher r was found for non-linear regression in all tested groups. Areas under receiver operation curves were calculated for cut points His ≥ 5 and > 33% and were found in the range of 0.77-0.86. Fibrosis influences the calculation of Φ(fat) and different slopes were obtained for fibrosis stages F0-F1 and F2-F3, respectively.
Significant correlation was found between the results of histology and 1H MRS measurement of liver fat content. The method is suitable for non-invasive repetitive examination of liver fat in liver-transplants patients between protocol biopsies and for the screening of steatosis in other liver diseases.
在几种非侵入性的肝脏脂肪分析方法中，磁共振成像和光谱（MRS）起着最重要的作用。本研究描述了一组肝移植患者肝脏脂肪容积分数Φ（fat）的 1H MRS 在 3T 测量，这些患者是新发脂肪变性的高危人群。
77 例接受常规移植后检查的肝移植受者分为三组：CON-PAT（交叉验证测试的对照组，48 例）、PAT-PAT（交叉验证测试的患者组，29 例）和 PAT（汇总数据）。使用单体素 1H MRS 在 3T 进行Φ（fat）的测定，并将组织学结果（His）作为参考标准。
线性和非线性回归模型用于描述Φ（fat）和 His 之间的关系。两种模型均具有强相关性，r = 0.83-0.94（P < 0.001）；在所有测试组中，非线性回归的 r 值更高。为 His≥5 和>33%的切点计算了接收器操作曲线的面积，范围在 0.77-0.86 之间。纤维化影响Φ（fat）的计算，并且在纤维化阶段 F0-F1 和 F2-F3 之间分别获得了不同的斜率。
肝脂肪含量的组织学和 1H MRS 测量结果之间存在显著相关性。该方法适用于肝移植患者在协议活检之间进行非侵入性重复检查肝脏脂肪，并适用于其他肝脏疾病中脂肪变性的筛查。
