^(18)氟标记脱氧葡萄糖正电子发射断层脑显像对癫痫患者致痫灶的定位和手术疗效的预测价值

^(18)F-FDG PET cerebral imaging for localizing epileptogenic foci and its relation to predicting operative outcome

目的 探讨18氟标记脱氧葡萄糖 (18F FDG)正电子发射断层 (PET)脑显像皮质代谢改变与癫痫患者致痫灶的关系 ,及其对手术方式选择和疗效预测的价值。方法 经手术治疗的 72例癫痫患者 (男 49例 ,女 2 3例 ,平均年龄 2 4岁 )术前行18F FDGPET脑显像并与同期磁共振 (MRI)、视频脑电图 (VEEG)结果进行比较 ,全部进行了疗效随访 (3～ 2 4个月 ,平均 15个月 ) ,其中 2 0例术后复查了18F FDGPET脑显像。结果 72例患者术前PET显像均有皮质代谢改变 ,1例表现发作期高代谢 ,71例表现发作间期低代谢。18F FDG代谢改变检出率高于MRI,其定位定侧准确性高于VEEG ,但多发低代谢灶不一定全是致痫灶。术后FDG显像有助于判断低代谢灶性质。皮质低代谢灶合并同侧丘脑和 /或对侧小脑代谢减低 ,术前术后显像对比表明系功能性变化。术前FDGPET图像分型与手术方式和术后疗效相关。结论 手术前后FDGPET图像对比有助于评价代谢改变与癫痫灶的关系 。

Objective To find out the relationship between FDG PET image pattern and epileptogenic focus localization and predict prognosis by comparing pre and post surgical FDG images with operative effects. Methods 72 patients with epilepsy who underwent surgery (49M, 23F, aged 24.3 years on average) were studied with pre surgical FDG PET cerebral imaging and followed up (av. 15 months, 3 24months) for assessment of seizure control. 20 of them were studied with post surgical FDG PET. The accuracy of localization of epileptogenic foci of FDG PET was compared with that of VEEG and MRI. The relationship between pre and post surgical FDG metabolic image pattern and surgical outcome was evaluated. Results (1) 71 patients showed pre surgical interictal focal hypometabolism. 1 patient with continuous seizure showed ictal hypermetabolic focus. (2) FDG PET could localize the seizure foci in patients whose EEG showed bilateral or no definite epileptoform discharge. The rate of detection of epileptogenic foci with FDG PET was much higher than that with MRI. Since hypometabolic foci were non specific, not all hypometabolic foci were epileptogenic. The correlation between postoperative FDG PET and surgical effect could help determine the nature of metabolic focus. (3) Hypometabolism of ipsilateral thalamus and/or contralateral cerebellum with temporal lobe lesion was secondary functional change. (4) The patternization of cerebral images was helpful to surgical planning and helped predict operative outcome. Conclusion Comparison of pre surgical with post surgical FDG PET images help determine the nature of hypometabolic foci. The patternization of FDG PET images help the surgeon select patients, plan type of operation and predict surgical effect.