Cendes F, Li L M, Watson C, Andermann F, Dubeau F, Arnold D L
Department of Neurology and Neurosurgery, Montreal Neurological Institute and Hospital, McGill University, Quebec, Canada.
Arch Neurol. 2000 Apr;57(4):497-500. doi: 10.1001/archneur.57.4.497.
To investigate the concordance between scalp electroencephalogram (EEG) lateralization and side of hippocampal atrophy in patients with temporal lobe epilepsy (TLE).
We studied 184 consecutive patients with TLE without lesions other than those compatible with mesial temporal sclerosis. In this study, we studied specifically hippocampal atrophy and the results of scalp EEG investigation. Patients were classified according to the localization of interictal epileptiform discharges as unilateral, bilateral asymmetric, and bilateral symmetric. The EEG seizure onsets were also classified separately as unilateral, bilateral asymmetric, and bilateral symmetric. The hippocampal atrophy was determined by volumetric measurements using high-resolution magnetic resonance imaging (MRIVol).
Only 3% of patients had discordance between the ictal and interictal EEG lateralizations; however, none of these had unilateral interictal EEG abnormalities. Interictal EEGs were considered unilateral in 62.0% of patients, bilateral asymmetric in 31.5%, and bilateral symmetric in 6.5%. Ictal EEGs were considered unilateral in 63.5% of patients, bilateral asymmetric in 30.0%, and bilateral symmetric in 6.5%. The MRIVol showed unilateral hippocampal atrophy in 60.9% of patients, bilateral asymmetric hippocampal atrophy in 19.0%, symmetric hippocampal atrophy in 3.8%, and normal volumes in 16.3%. There was a significant concordance between MRIVol lateralization and both interictal and ictal EEG lateralization (P<.001). All patients with unilateral hippocampal atrophy had concordant interictal and ictal EEG lateralization. Six (18.2%) of the 33 patients with bilateral asymmetric hippocampal atrophy had MRI lateralization discordant with EEG lateralization.
We found a strong concordance between EEG and MRIVol lateralization in patients with TLE. Unilateral hippocampal atrophy predicted ipsilateral interictal epileptiform abnormalities and ipsilateral seizure onsets with no false lateralization. Previous studies in addition to the present series support that a concordant outpatient EEG evaluation in patients with TLE and unilateral hippocampal atrophy would obviate the need for inpatient EEG monitoring.
研究颞叶癫痫（TLE）患者头皮脑电图（EEG）定位与海马萎缩侧之间的一致性。
我们研究了184例连续的TLE患者，这些患者除了符合内侧颞叶硬化外无其他病变。在本研究中，我们专门研究了海马萎缩情况以及头皮EEG检查结果。患者根据发作间期癫痫样放电的定位分为单侧、双侧不对称和双侧对称。EEG发作起始也分别分为单侧、双侧不对称和双侧对称。使用高分辨率磁共振成像（MRIVol）通过体积测量确定海马萎缩情况。
仅3%的患者发作期和发作间期EEG定位不一致；然而，这些患者均无单侧发作间期EEG异常。62.0%的患者发作间期EEG为单侧，31.5%为双侧不对称，6.5%为双侧对称。63.5%的患者发作期EEG为单侧，30.0%为双侧不对称，6.5%为双侧对称。MRIVol显示60.9%的患者有单侧海马萎缩，19.0%为双侧不对称海马萎缩，3.8%为对称海马萎缩，16.3%体积正常。MRIVol定位与发作间期和发作期EEG定位之间存在显著一致性（P<0.001）。所有单侧海马萎缩的患者发作间期和发作期EEG定位一致。33例双侧不对称海马萎缩的患者中有6例（18.2%）MRI定位与EEG定位不一致。
我们发现TLE患者EEG与MRIVol定位之间有很强的一致性。单侧海马萎缩可预测同侧发作间期癫痫样异常和同侧发作起始，且无假定位。除本系列研究外，既往研究支持对TLE和单侧海马萎缩患者进行门诊EEG评估与住院EEG监测具有一致性，可避免住院EEG监测的必要性。
