^(18)F-FDG PET在颞叶外癫痫术前评估中的作用

Role of ^(18)F-FDG PET in the preoperative evaluation of extratemporal lobe epilepsy

目的分析^(18)F-FDG PET在颞叶外癫痫(ETLE)患者术前评估中的应用价值,并探讨提高其定位准确性的改进方法。方法纳入2006年1月至2022年11月间于北京协和医院行手术治疗、最终证实致痫灶位于颞叶外的41例患者[男25例、女16例,年龄(22.7±7.5)岁],采用视觉及半定量方法回顾性分析其术前独立^(18)F-FDG PET显像,以及^(18)F-FDG PET与MRI联合应用对致痫灶检出的准确性,及对治疗决策的影响。采用Fisher确切概率法分析数据。结果41例患者中,独立^(18)F-FDG PET视觉分析发现40例颞叶外脑部代谢异常,其中26例为单一部位的局灶性代谢异常,定位为致痫灶;14例为多灶性代谢异常,其中8例经半定量分析进一步明确致痫灶。有1例PET视觉分析阴性的患者发现其MRI异常信号部位存在微小代谢增高灶。在13例独立MRI阅片结果为阴性的患者中,9例在^(18)F-FDG PET所示代谢减低脑区发现存在微小结构异常。^(18)F-FDG PET帮助18例(43.9%,18/41)患者改善临床决策。73.2%(30/41)的患者术后无癫痫发作,其中局灶性与多灶性^(18)F-FDG PET代谢异常患者间预后无明显差异[73.1%(19/26)和10/14,P=1.000]。结论^(18)F-FDG PET对于ETLE患者是一种有用的术前评估工具。半定量分析有助于在多灶性代谢异常中检出致痫灶。^(18)F-FDG PET和MRI联合评估可提高颞叶外致痫灶定位的准确性。

Objective To analyze the application value of ^(18)F-FDG PET in the preoperative evaluation of patients with extratemporal lobe epilepsy(ETLE)and explore improved methods to enhance its localization accuracy.Methods A total of 41 patients(25 males,16 females,age(22.7±7.5)years)who underwent surgery and ultimately confirmed ETLE in Peking Union Medical College Hospital between January 2006 and November 2022 were enrolled.The accuracy of preoperative independent ^(18)F-FDG PET imaging and the combined application of ^(18)F-FDG PET and MRI in detecting epileptogenic foci and their impacts on treatment decisions were retrospectively analyzed by using visual and semi-quantitative methods.Fisher′s exact test was used to analyze the data.Results In all 41 patients,40 cases were found metabolic abnormalities in extratemporal lobe by independent ^(18)F-FDG PET based on visual analysis.Among them,26 showed unifocal metabolic abnormalities,which were localized as epileptogenic foci.Fourteen patients showed multifocal metabolic abnormalities,and the epileptogenic foci were further verified in 8 cases through semi-quantitative analysis.In 1 case with negative PET visual analysis,a micro-metabolism focus was found at the abnormal MRI signal area.Among 13 patients with negative independent MRI,9 were found microstructures abnormalities in brain regions with hypometabolism.^(18)F-FDG PET improved clinical decision-making in 18 patients(43.9%,18/41).There were 30 patients(73.2%,30/41)with seizure-free postsurgery,and the prognosis was not significantly different between patients with unifocal ^(18)F-FDG PET metabolic pattern and those with multifocal ones(73.1%(19/26)vs 10/14,P=1.000).Conclusions ^(18)F-FDG PET can be a useful diagnostic tool for patients with ETLE.Semi-quantitative analysis helps to detect more epileptogenic foci with multifocal metabolic abnormalities.The combined evaluation of ^(18)F-FDG PET and MRI can improve the accuracy in localizing epileptogenic foci outside the temporal lobe.