同反相位图像减影技术及T2校正^1H-MRS定量分析非酒精性脂肪肝的临床研究  

Clinical evaluation of nonalcoholic fatty liver disease with in-phase and out-of-phase subtraction MR imaging and T_2 corrected proton ~1H-MR spectroscopy

作　　者：石喻[1] 郭启勇[2] 夏菲[1] 张兰[1] 卞胜昕[1] 

机构地区：[1]中国医科大学附属盛京医院,辽宁沈阳110004 [2]中国医科大学附属盛京医院放射科,辽宁沈阳110004

出　　处：《中国临床医学影像杂志》2012年第4期248-252,共5页Journal of China Clinic Medical Imaging

基　　金：国家自然科学基金资助(81071123)

摘　　要：目的:探讨双回波同反相位(IP-OP)减影法及T2校正1H-MRS定量分析非酒精性脂肪肝患者的肝脂肪含量(LFC)的可行性。方法:对42例临床怀疑脂肪肝的患者行3D T1WI IP-OP成像结合减影技术及1H-MRS检查。选取5名患者行多次回波PRESS序列以测量水、脂的T2值。采用非参数Spearman分析及Mann-Whitney U检验,比较评价两种影像方法定量分析脂肪肝的能力。结果:1H-MRS各峰值采用T2进行校正(T2水=33.1 ms,T2亚甲基=64.2 ms)。IP-OP减影法、1H-MRS对脂肪肝定性诊断的敏感度及特异度分别为89.2%、100%及91.2%、100%。IP-OP减影法及1H-MRS测得的脂肪含量与病理结果均呈显著的相关性(r=0.80,0.92;P<0.01)。1H-MRS可有效区分无脂肪肝与轻度脂肪肝(Z=-2.97,P<0.01)、轻度与中度脂肪肝(Z=-3.72,P<0.01)、中度与重度脂肪肝(Z=-3.25,P<0.01),IP-OP减影法可有效区分无脂肪肝与轻度脂肪肝(Z=-2.54,P<0.01)、轻度与中度脂肪肝(Z=-3.72,P<0.01),不能区分中度与重度脂肪肝(Z=-1.77,P=0.08)。1H-MRS、IP-OP减影法测得的LFC均低于病理结果(除无脂肪肝组外,Z≤-2.21,P<0.05)。结论:IP-OP减影法可简单快速的诊断脂肪肝程度,1H-MRS对脂肪肝的定量诊断具有更高的准确性。Objective： To compare the T1 weighted in-phase and out-of-phase magnetic resonance imaging（IP-OP） with subtraction techniques and T2 corrected proton 1H-MR spectroscopy（1H-MRS） in the assessment of liver fat content（LFC） in patients with nonalcoholic fatty liver disease.Methods： IP-OP MR imaging and 1H-MRS were performed in 42 patients using a 3T MR unit.Subtraction images were made from pairs of IP and OP images.T2 relaxation measurements were performed in five patients by using a multi echo PRESS sequence.LFC measured by IP-OP and 1H-MRS were compared with histological results using spearman analysis and Mann-Whitney U test.Results： LFC measured by 1H-MRS were corrected by T2 relaxation（T2water=33.1 ms,T2fat=64.2 ms）.Sensitivity and specificity of IP-OP substraction and 1H-MRS to detect steatosis was 89.2%,100% and 91.2%,100%,respectively.IP-OP MR imaging and 1H-MRS measurements of LFC had strong correlation with histopathologic steatosis assessment（r=0.80,0.92;P0.01）.IP-OP and 1H-MRS showed differences across steatosis grades： none versus mild,mild versus moderate and moderate versus severe grade（expect that IP-OP cannot differentiate moderate from severe grade,Z≤-2.54,P0.01）.The LFC measured by IP-OP and 1H-MRS were significantly lower than pathology（expect for non fatty liver group,Z≤-2.21,P0.05）.Conclusion： IP-OP is a quick and effective way to detect steatosis for clinic.1H-MRS has better diagnostic accuracy in depicting hepatic steatosis than IP-OP.

关 键 词：脂肪肝 磁共振成像 磁共振波谱学 

分 类 号：R575.5[医药卫生—消化系统] R445.2[医药卫生—内科学]