Koutroumanidis M, Binnie C D, Elwes R D, Polkey C E, Seed P, Alarcon G, Cox T, Barrington S, Marsden P, Maisey M N, Panayiotopoulos C P
Epilepsy Surgery Centre, King's College Hospital, London, UK.
J Neurol Neurosurg Psychiatry. 1998 Aug;65(2):170-6. doi: 10.1136/jnnp.65.2.170.
The phenomenon of interictal regional slow activity (IRSA) in temporal lobe epilepsy and its relation with cerebral glucose metabolism, clinical data, MRI, and histopathological findings was studied.
Interictal 18F-fluorodeoxyglucose positron emission tomography (FDG PET) was performed under continuous scalp EEG monitoring in 28 patients with temporal lobe epilepsy not associated with intracranial foreign tissue lesions, all of whom subsequently underwent resective surgery. Regions of interest (ROIs) were drawn according to a standard template. IRSA was considered lateralised when showing a 4:1 or greater ratio of predominance on one side.
Sixteen patients (57%) had lateralised IRSA which was always ipsilateral to the resection and of maximal amplitude over the temporal areas. Its presence was significantly related to the presence of hypometabolism in the lateral temporal neocortex (p=0.0009). Logistic regression of the asymmetry indices for all measured cerebral regions confirmed a strong association between IRSA and decreased metabolism of the posterior lateral temporal neocortex only (p=0.009). No significant relation could be shown between slow activity and age at onset, duration of the epilepsy, seizure frequency, and MRI evidence for hippocampal atrophy. Furthermore, IRSA was not specifically related to mesial temporal sclerosis or any other pathology.
Interictal regional slowing in patients with temporal lobe epilepsy not associated with a mass lesion is topographically related to the epileptogenic area and therefore has a reliable lateralising, and possibly localising, value. Its presence is irrelevant to the severity or chronicity of the epilepsy as well as to lateral deactivation secondary to neuronal loss in the mesial temporal structures. Although slow EEG activity is generally considered as a non-specific sign of functional disturbance, interictal regional slowing in temporal lobe epilepsy should be conceptualised as a distinct electrographic phenomenon which is directly related to the epileptogenic abnormality. The strong correlation between interictal regional slowing and lateral temporal hypometabolism suggests in turn that the second may delineate a field of reduced neuronal inhibition which can receive interictal and ictal propagation.
研究颞叶癫痫发作间期局部慢波活动（IRSA）现象及其与脑葡萄糖代谢、临床资料、磁共振成像（MRI）和组织病理学发现的关系。
对28例无颅内异物病变的颞叶癫痫患者在连续头皮脑电图监测下进行发作间期18F-氟脱氧葡萄糖正电子发射断层扫描（FDG PET），所有患者随后均接受了切除手术。根据标准模板绘制感兴趣区（ROI）。当IRSA在一侧显示出4:1或更高的优势比时，认为其具有定位性。
16例患者（57%）有定位性IRSA，其总是与切除部位同侧，且在颞区振幅最大。其存在与外侧颞叶新皮质低代谢的存在显著相关（p=0.0009）。对所有测量脑区不对称指数的逻辑回归证实，IRSA仅与外侧颞叶新皮质后部代谢降低密切相关（p=0.009）。慢波活动与发病年龄、癫痫病程、发作频率以及海马萎缩的MRI证据之间未显示出显著关系。此外，IRSA与内侧颞叶硬化或任何其他病理改变无特异性关联。
无占位性病变的颞叶癫痫患者发作间期局部慢波与致痫区在地形学上相关，因此具有可靠的定位价值，甚至可能具有定侧价值。其存在与癫痫的严重程度、慢性病程以及内侧颞叶结构神经元丢失继发的外侧失活无关。虽然脑电图慢波活动通常被认为是功能障碍的非特异性征象，但颞叶癫痫发作间期局部慢波应被视为一种独特的脑电图现象，它与致痫异常直接相关。发作间期局部慢波与外侧颞叶低代谢之间的强相关性反过来表明，后者可能描绘了一个神经元抑制减弱的区域，该区域可接受发作间期和发作期的传播。
