屏气与呼吸触发氢质子磁共振波谱量化肝脏脂肪含量的比较

Comparison of breath-hold and respiratory-triggered proton MR spectroscopy in quantification of liver fat content

目的:比较多次屏气与呼吸触发氢质子磁共振波谱(hydrogen 1 magnetic resonance spectroscopy,1H-MRS)对肝脏脂肪含量量化的一致性和相关性。方法 :60例受试者使用1.5 T磁共振扫描仪在肝脏Ⅶ段分别行多次屏气和呼吸触发1H-MRS采集。分别记录波谱曲线中亚甲基峰和水峰下面积,计算脂肪分数。计算两者的Pearson相关系数、Bland-Altman 95%一致性界限和一致性相关系数。结果:多次屏气和呼吸触发1H-MRS得到的平均肝脏脂肪含量分别为(8.6±8.7)%和(9.4±9.3)%,两者高度相关(r=0.973,P<0.0001;一致性相关系数为0.95)。用Bland-Altman方法 ,91.7%点都在95%一致性界限内。结论 :多次屏气与呼吸触发1H-MRS均能用于量化肝脏脂肪含量。这两种方法高度相关且一致性良好。

Objective To compare the consistency and correlation of multiple breath-hold （BH） with respiratory-triggered （RT） 1H-MRS for quantification of hepatic lipid content. Methods Sixty subjects were underwent RT 1H-MRS of the liver （Couinaud segment VII） and BH 1H-MRS at 1.5 Tesla Magnetic Resonace Imaging （MRI）. The peak areas of water and methylene obtained on RT and BH 1H-MRS were recorded respectively and the liver fat fraction was calculated. Pearson correlation coefficient , Bland-Altman 95% limit of agreement, and concordance correlation coefficient were calculated. Results Mean liver fat fraction measured in RT and BH 1H-MRS were （8.6 ± 8.7）% and （9.4 ± 9.3）% respectively. There was a strong correlation between RT and BH 1H-MRS（r = 0.973, P 〈 0.000 1, concordance correlation coefficient = 0.95）. With the Bland-Altman method, 91.7% data points were within the 95% limits of agreement. Conclusion RT and BH 1H-MRS are alternative tools for intrahepatic lipid quantification. These two methods have a strong correlation and perfect consistency.