3.0T MRI多回波Dixon技术对非酒精性脂肪性肝病患者肝脏脂肪的定量分析

目的 探讨3.0T MRI多回波(multi-echo,ME) Dixon技术对非酒精性脂肪性肝病(NAFLD)患者的肝脏脂肪定量分析的可行性.方法 前瞻性地纳入自愿加入本研究的志愿者20例,其中女性NAFLD患者4例,正常对照者1例;男性NAFLD患者12例,正常对照者3例.进行常规肝脏MRI平扫、ME序列检查,之后再进行单体素磁共振波谱分析(MRS)检查.检查结束后处理数据,记录Screening Dixon的脂肪分数(fatfraction,FF)值和Histo序列自动得出的单体素MRS的FF值,再手动在ME Dixon的FF图中测得3个感兴趣区(ROI)的FF值.最后分别对各FF值进行Spearman相关性分析.结果 Screening Dixon与ME Dixon的3个ROI区域测得的FF值呈高度正相关(r=0.842、0.959、0.945,P值均＜0.001).Screening Dixon及ME Dixon的3个ROI区域测得的FF值与Histo得出的单体素MRS所测得的FF值呈高度正相关(r=0.971、0.842、0.959、0.945,P值均＜0.001).结论 采用3.0T MRI ME Dixon成像技术对NAFLD患者进行肝脏脂肪含量的评估是可行的,并与单体素MRS所得结果呈高度正相关.其结果对于NAFLD患者的诊断、随访和干预监测均具有一定的临床价值.

3.0T MRI multi-echo Dixon technique in quantitative analysis of liver fat in patients with nonalcoholic fatty liver disease

Objective To investigate the feasibility of using 3.0T MRI multi-echo (ME) Dixon technique for liver fat quantification in patients with nonalcoholic fatty liver disease (NAFLD). Methods Twenty volunteers were enrolled in this prospective study, and they included 16 NAFLD patients (12 males and 4 females) and 4 healthy volunteers (3 males and one female). All volunteers were examined by routine liver MRI, ME Dixon technique and single-voxel MRS. After examination, the fat fraction (FF) value of Screening Dixon and the FF value of single-voxel MRS with Histo sequence were recorded, and the FF values of 3 regions of interest (ROIs) in the fat fraction map of ME Dixon were manually measured. Finally, the FF values were analyzed with Spearman correlation analysis. Results The Screening Dixon FF value was positively correlated with the FF values of three ROIs of ME Dixon (r=0.842, 0.959, and 0.945 respectively,all P<0.001). Similarly, positive correlation was also found for the FF values of Screening Dixon and 3 ROIs of ME Dixon with the FF value of single-voxel MRS with Histo sequence(r=0.971, 0.842, 0.959, and 0.945 respectively,all P<0.001). Conclusion It is feasible to use 3.0T MRI ME Dixon for evaluating liver fat content in patients with NAFLD, and its results are positively correlated with those of single-voxel MRS. It is valuable for the diagnosis, follow-up and intervention of NAFLD patients.