多体素氢质子磁共振波谱对颞叶癫癎定位作用的临床研究

Clinical study on multi-voxel proton magnetic resonance spectroscopy （1H-MRS） for location of temporal lobe epilepsy

目的研究多体素氢质子磁共振波谱(1H-MRS)对颞叶癫癎的致癎灶定位作用。方法对36例颞叶癫癎病人和15例正常人进行MRI扫描和1H-MRS成像,采样容积为8.8mm×8.8mm×8.0mm,选取海马前部相邻3个体素,取平均值,比较病侧、健侧以及对照组氮-乙酰天门氨酸(NAA)/肌酸+胆碱复合物(Cr+Cho)等比值的差异。并分析MRI与1H-MRS在定位致癎灶方面的差异。结果与对照组比较,病侧NAA/(Cr+Cho)明显降低,差异具有统计学意义。MRS定位率50%,联合应用MRI与1H-MRS定位准确率可达到83.3%;MRI阴性病例中45.5%的病人MRS为阳性。结论1H-MRS可有效定位颞叶致癎灶,尤其是MRI阴性表现的颞叶癫癎。联合应用MRI与1H-MRS可提高定位致癎灶的比例。

Objective To study the role of multi-voxel proton magnetic resonance spectroscopy （^1H-MRS） in location of epileptogenic focus for temporal lobe epilepsy （TLE）. Methods MRI and ^1H-MRS imaging were performed in 36 patients with TLE and 15 healthy volunteers. Multi-voxel spectra of both the hippocampi were obtained and the voxel was flamed of 8.8 mmx 8.8 mm x 8.0 mm. Three neighbor voxels in anterior hippocampus were selected to be averaged. The difference in N-acetylaspartate （NAA）/creatine ＋ choline （Cr ＋ Cho） ratio between various groups and the role of MRI and ^1H-MRS in location of epileptogenic focus were compared. Results The NAA/（Cr ＋ Cho） ratio of patients was significantly lower than that of the control group. Fifty percent of the patients were positive for ^1H-MRS in the focus side, which was identical to the seizure focus. The accuracy rate of the location reached to 83.3% when MRI and ^1H-MRS were combined, and 45.5% of patients with negative MRI showed positive ^1H-MRS. Conclusion The ^1H-MRS is an effective method for location of epileptogenic focus for TLE, especially for patients with negative MRI, and combination of MRI and ^1H-MRS can greatly improve the accuracy rate of location.