发作间期颞叶癫痫的^(18)氟-脱氧葡萄糖PET和颞叶MRI的对比研究

Comparative study of FDG PET and MRI in interictal temporal lobe epilepsy

目的 对脱氧葡萄糖 (18F DG)PET与MRI显像方法进行对比研究 ,观察PET与MRI在癫痫灶定位诊断中各自的优缺点。方法 32例经临床及脑电图诊断的颞叶癫痫患者分别在同期进行发作间期18F DGPET和MRI检查 ,用MRI的FLAIR序列扫描来显示海马结构 ,其中 2 6例定位明确的患者进行了颞叶切除手术 ,并进行术后的随访。图像分析通过目测的方法及图像信号强度测量的方法进行比较。 6例未行手术的患者中 ,3例因双侧病灶未行手术 ,1例为胶质瘤 ,另 2例失去随访。结果 2 6例进行颞叶切除的患者中 ,发现18F DGPET对癫痫灶检出率为 92 .30 % (2 4/2 6 ) ,而MRI对癫痫灶检出率为 80 .76 % (2 1/2 6 ) ,18F DGPET对癫痫灶的探测敏感性高于MRI,但MRI的图像定位精确程度则明显优于PET。结论 PET、MRI、皮层脑电图对癫痫病灶定位的一致性是手术成功的前提 ,仅从颞叶癫痫的定位诊断来看 ,PET比FLAIRMRI灵敏 ,但由于缺乏特异性 ,仅18F DGPET的低代谢并不能完全确定癫痫灶的位置 ,故需要其他的诊断措施加以肯定。而且18F DGPET和FLAIRMRI序列有互补的作用 ,两者的结合 。

Objective The localization of epileptogenic foci may be accomplished by clinical observations, electroencephalogram (EEG), MRI and 18 F DG PET scans. These tests have also been used at various epilepsy centers to help identify candidates who might benefit from such operation. Interictal PET scans have demonstrated hypometabolism in areas concordant with the epileptogenic. However, fluid attenuated inversion recovery (FLAIR) imaging shows high sensitivity in detecting epileptogenic foci, our purpose is to correlate the FLAIR MRI scan and 18 F DG PET. Methods FLAIR MR and 18 F DG PET scans of 32 interictal patients with temporal lobe epilepsy proved by clinical history and EEG were assessed, 26 cases had been operated and followed up. 3 patients were excluded beacuse of presence of bilaterial temporal foci, 1 patient was found to have glioma, another 2 were lost to follow up. Results The sensititivity of localizating epileptogenic foci by FLAIR sequence was 80.76%; 18 F DG PET 92.36%. PET showed higher sensitivity. However, MRI was more accurate in localization because of it's high resolution. Conclusion 18 F DG PET has high potential ability in the detection of epileptogenic foci. FLAIR sequence imaging with high signal intensity of CSF may become a routine test for localization of temporal epilepsy. Combined 18 F DG PET and FLAIR sequence would be of higher predictive value in the detection of epileptogenic foci before operation because of their complementary effect.(Shanghai Med J, 2000,23∶528 530)