顺磁性对比剂Gd-DTPA对短暂性脑缺血发作^1H MRS的影响

Effects of Paramagnetic Contrast Agent Gd-DTPA on Magnetic Resonance Spectroscopy in Transient Ischemic Attack

目的:分析短暂性脑缺血发作(TIA)患者MR脑灌注成像(PWI)后顺磁性对比剂钆喷酸葡甲胺(Gd-DTPA)对质子磁共振波谱(1H MRS)的影响,探讨用PWI检查指导1H MRS定位的可行性。方法:对20例临床诊断为TIA的患者行PWI检查,分别在PWI检查前后于双侧半卵圆中心行1H MRS检查,扫描参数及兴趣区(VOI)均相同。对比分析注射Gd-DTPA前后两次1H MRS主要代谢产物氮-乙酰天门冬氨酸(NAA)、胆碱复合物(Cho)和肌酸复合物(Cr)谱线的形态(峰高和半高宽)及相对浓度值(峰下面积比值)。结果:注射Gd-DTPA前后两次1H MRS检查NAA、Cho和Cr谱线的形态未发现明显改变,同一区域代谢物谱线的各项参数差异均无显著性意义(P>0.05)。结论:TIA患者PWI检查注射顺磁性对比剂Gd-DTPA对1H MRS没有明显影响,可以通过PWI显示的灌注异常,指导TIA患者的1H MRS定位。

Objective：To investigate the effects of gadolinium diethylene triaminepentaacetic acid （Gd-DTPA） on ^1 H magnetic resonance spectroscopy （^1H MRS） performed in patients with transient ischemic attacks （TIA） shortly after MR cerebral perfusion weighted imaging （PWI）,and to evaluate the feasibility of using PWI to guide the selection of volume of interest （VOI） localization for ^1H MRS. Methods：20 patients with clinically diagnosed TIA were examined with ^1H MRS before and after PWI scans. The same technical parameters and VOI locations were respectively set in the pre- and post-PWI H MRS. The values of peak height, width at half maximum and ratios of peak area of N-ace-yl aspartate acid （NAA）,choline （Cho） and creatine （Cr） were acquired and measured before and after the administration of Gd-DTPA （before and after PWI） ,and the data were individually and correlatively compared. Results： There were no statistically significant differences （P〉0.05） between the measured metabolite levels acquired in the corresponding VOIs of the pre- and post contrast ^1H MRS. Conclusion： There was no significant influence of paramagnetic MR contrast medium （Gd-DTPA） on the results and examination quality of ^1H-MRS in case the spectroscopy was immediately undergone after PWI in TIA patients, meanwhile, it indicated that PWI might help the guidance of more accurate VOI localization for ^1H-MRS in accordance to the abnormal perfusion zones shown in the MR PWI scan.