Liew Clarissa J, Lim Young-Min, Bonwetsch Robert, Shamim Sadat, Sato Susumu, Reeves-Tyer Patricia, Herscovitch Peter, Dustin Irene, Bagic Anto, Giovacchini Giampiero, Theodore William H
Clinical Epilepsy Section, National Institutes of Health, Bethesda, Maryland 20892, USA.
Epilepsia. 2009 Feb;50(2):234-9. doi: 10.1111/j.1528-1167.2008.01789.x. Epub 2008 Sep 17.
Positron emission tomography (PET) with (18)F-fluorodeoxyglucose (FDG) shows widespread hypometabolism even in temporal lobe epilepsy (TLE) patients with mesial temporal foci. (18)F-trans-4-fluoro-N-2-[4-(2-methoxyphenyl) piperazin-1-yl]ethyl-N-(2-pyridyl)cyclohexane carboxamide ((18)F-FCWAY) PET may show more specific 5-HT(1A)-receptor binding reduction in seizure initiation than in propagation regions. (18)FCWAY PET might be valuable for detecting epileptic foci, and distinguishing mesial from lateral temporal foci in MRI-negative patients with TLE.
We performed (18)F-FCWAY-PET and (18)F-FDG-PET in 12 MRI-negative TLE patients who had had either surgery or subdural electrode recording, and 15 healthy volunteers. After partial volume correction for brain atrophy, free fraction-corrected volume of distribution (V/f1) measurement and asymmetry indices (AIs) were computed. We compared (18)F-FCWAY-PET and (18)F-FDG-PET results with scalp video electroencephalography (EEG), invasive EEG, and surgical outcome.
Mean (18)F-FCWAY V/f1, compared with normal controls, was decreased significantly in fusiform gyrus, hippocampus, and parahippocampus ipsilateral to epileptic foci, and AIs were significantly greater in hippocampus, parahippocampus, fusiform gyrus, amygdala, and inferior temporal regions. Eleven patients had clearly lateralized epileptogenic zones. Nine had congruent, and two nonlateralized, (18)F-FCWAY PET. One patient with bitemporal seizure onset had nonlateralized (18)F-FCWAY-PET. (18)F-FDG-PET showed congruent hypometabolism in 7 of 11 EEG-lateralized patients, bilateral hypometabolic regions in one, contralateral hypometabolism in one, as well as lateralized hypometabolism in the patient with bitemporal subdural seizure onset. Patients with mesial temporal foci tended to have lower superior and midtemporal (18)F-FCWAY V/f1 binding AI than those with lateral or diffuse foci.
(18)F-FCWAY-PET can detect reduced binding in patients with normal MRI, and may be more accurate than (18)F-FDG-PET.
正电子发射断层扫描(PET)结合(18)F - 氟脱氧葡萄糖(FDG)显示,即使在患有内侧颞叶病灶的颞叶癫痫(TLE)患者中也存在广泛的代谢减低。(18)F - 反式 - 4 - 氟 - N - 2 - [4 - (2 - 甲氧基苯基)哌嗪 - 1 - 基]乙基 - N - (2 - 吡啶基)环己烷甲酰胺((18)F - FCWAY)PET可能在癫痫起始区域比在传播区域显示出更特异性的5 - HT(1A)受体结合减少。(18)FCWAY PET对于检测癫痫病灶以及在MRI阴性的TLE患者中区分内侧颞叶病灶和外侧颞叶病灶可能具有重要价值。
我们对12例接受过手术或硬膜下电极记录的MRI阴性TLE患者以及15名健康志愿者进行了(18)F - FCWAY - PET和(18)F - FDG - PET检查。在对脑萎缩进行部分容积校正后,计算了游离分数校正分布容积(V/f1)测量值和不对称指数(AI)。我们将(18)F - FCWAY - PET和(18)F - FDG - PET结果与头皮视频脑电图(EEG)、侵入性EEG及手术结果进行了比较。
与正常对照组相比,癫痫病灶同侧的梭状回、海马和海马旁回的平均(18)F - FCWAY V/f1显著降低,海马、海马旁回、梭状回、杏仁核和颞下区域的AI显著更高。11例患者有明确的癫痫起源侧化区域。9例患者的(18)F - FCWAY PET结果一致,2例结果无侧化。1例双侧颞叶发作患者的(18)F - FCWAY - PET结果无侧化。在11例EEG侧化的患者中,7例(18)F - FDG - PET显示代谢减低一致,1例为双侧代谢减低区域,1例为对侧代谢减低,还有1例双侧硬膜下颞叶发作患者显示侧化代谢减低。内侧颞叶病灶患者的颞上和颞中(18)F - FCWAY V/f1结合AI往往低于外侧或弥漫性病灶患者。
(18)F - FCWAY - PET可检测MRI正常患者的结合减少情况,且可能比(18)F - FDG - PET更准确。