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Neurocardiogenic (vasovagal/vasodepressor) syncope (NCS) is a reflex mediated loss of consciousness resulting from the failure of the autonomic nervous system to maintain adequate cerebral perfusion pressure. 1,2 Excessive peripheral venous pooling of blood in combination with aberrant responses of mechanoreceptors to compensatory cardiac hypercontractility results in a paradoxical reflex bradycardia and drop in peripheral vascular resistance. 3,4 The consequent cerebral hypoperfusion induces a transient loss of consciousness that is associated with abnormal movements (e.g. myoclonic jerks) in 12-90% of patients. 2,[5][6][7][8][9][10] Despite clinical guidelines that distinguish NCS ABSTRACT: Background: Neurocardiogenic syncope (NCS) can be mistaken as a seizure. We reviewed the frequency and diagnostic consequences of this misdiagnosis. Methods: A retrospective review of outpatient adult epilepsy clinic charts (QEII Health Sciences Centre, Halifax, NS) was conducted to identify NCS patients referred with a provisional diagnosis of seizures. Charts were reviewed in detail with an emphasis on the consequences of misdiagnosis. Results: Of 1506 consecutive referrals to the epilepsy clinic, 194 (12.9%) ultimately had a clinical diagnosis of NCS. Mean age was 38 +/-16 years (mean age of syncopal onset was 28 +/-16 years). Two-thirds of referrals were from primary care physicians (including emergency departments) and 18% from neurologists. Thirty-five percent were prescribed antiepileptic drugs (AEDs) prior to referral with eight patients (4.1%) experiencing hypersensitivity reactions. Three of five women had adverse pregnancy outcomes while taking AEDs. One-third of patients had restrictions placed on their driving privileges while 11 patients (5.7%) had their employment interrupted. Diagnostic modalities used in the work-up included EEG (90%), CT head (51%), and MRI head (15%). Conclusions: NCS is commonly misdiagnosed as epilepsy. Some patients had an incorrect diagnosis for > 10 years. Patients with this misdiagnosis are often excessively investigated, inappropriately treated, and have unnecessary restrictions placed on driving and employment. RÉSUMÉ: Syncope neurocardiogénique : fréquence et conséquences d'un diagnostic erroné d'épilepsie.Contexte : Une syncope neurocardiogénique (SNC) peut être prise à tort pour une crise convulsive. Nous revoyons la fréquence et les conséquences d'un tel diagnostic erroné. Méthodes : Nous avons effectué une révision rétrospective des dossiers de patients de la clinique externe d'épilepsie (QEII Health Sciences Centre, Halifax, NS) afin d'identifier les patients ayant présenté une SNC qui y ont été référés avec un diagnostic provisoire de crise convulsive. Les dossiers ont été révisés en détail, particulièrement en ce qui concerne les conséquences d'un diagnostic erroné. Résultats : On a posé ultérieurement un diagnostic de SNC chez 194 (12,9%) de 1506 patients consécutifs référés à la clinique d'épilepsie. L'âge moyen des patients était de 38 ± 16 ans et l'âge moyen au moment ...

Summary Purpose:  A retrospective study of lamotrigine (LTG)–valproic acid (VPA) combination therapy in medically refractory epilepsy. Methods:  Patients were identified with an adult epilepsy clinic database and were included if they had been on LTG–VPA combination therapy for at least 6 months. Patient demographics and information about epilepsy type, severity, and degree of medical intractability were obtained by retrospective chart review. The primary outcome measure was change in baseline seizure frequency, and patients were stratified into three groups: (i) seizure‐free, (ii) improved (at least 50% reduction in baseline seizure frequency), and (iii) not improved. Results:  Thirty‐five patients met all inclusion–exclusion criteria. Epilepsy type was generalized in 25 patients (71%) and partial in 10 patients (29%). Before LTG–VPA treatment, 27 of 35 (77%) experienced disabling seizures on a monthly basis, and 17 of 35 (49%) of patients had at least one disabling seizure per week. Patients had previously failed treatment with a median of five antiepileptic drugs (AEDs), alone or in combination. With LTG–VPA therapy, 18 (51.4%) remained completely seizure‐free, four (11.4%) were improved, and 13 (37.1%) were unimproved. Median follow‐up was 42 months. Of the 22 patients who improved, 11 had previously failed LTG and VPA monotherapy. There was no significant difference between improved and unimproved patients with respect to demographics, epilepsy type or severity, or number of previously failed AEDs. Discussion:  The combination of LTG and VPA should be considered in patients with medically refractory epilepsy. The effectiveness of this combination appears to be independent of epilepsy type or patient demographics.

Summary:Purpose: The concordance of lateralized EEG postictal polymorphic delta activity (PPDA) to the side of seizure origin in temporal lobe epilepsy (TLE) has received limited study. Our objective was to study the lateralizing value of PPDA in patients with documented TLE.Methods: A cohort of consecutive adults with TLE, detailed presurgical evaluation before temporal lobectomy, and minimal follow-up of 2 years were included. One author masked the ictal rhythm of presurgical EEGs and randomly presented 20 s of preictal and the postictal EEG to two electroencephalographers who were blind to all clinical data. They independently assigned PPDA to one of three categories: not present, bilateral, or lateralized (defined as newly appearing or an amplitude >50% of the preictal record).Results: Eighty seizures from 29 patients were studied. Fifteen patients had a left, and 14 had a right temporal lobectomy. Twenty-three patients were seizure free or substantially improved (defined as simple partial or nocturnal seizures only). Lateralized PPDA was present in 64% of all EEGs and at least one record from 22 (76%) patients. Lateralized PPDA, when present, was concordant with the side of surgery in 96% of the EEGs.Conclusions: Lateralized PPDA is highly predictive of the side of ultimate temporal lobectomy, and by inference the side of seizure origin.

Electroencephalography (EEG) remains the single most important physiologic test of the cerebral cortex 1,2 . In temporal lobe epilepsy (TLE), focal interictal and ictal epileptiform discharges help in identifying the involved cortical areas 3 . Several nonepileptiform EEG abnormalities can also be seen in TLE. Scalp and sometimes invasive EEG recordings are needed for accurate localization of the seizure onset. The development of video-EEG monitoring has allowed careful correlation of clinical semiology with simultaneous EEG recordings 4 . This paper will review the EEG characteristics of TLE. EEG RECORDING I. Scalp EEG recordingThe 10-20 electrode system is an internationally accepted standard method of measurement and application of EEG scalp electrodes 5 . The standard electrodes can detect only up to 58% of ABSTRACT: Electroencephalography (EEG) is an important tool for diagnosing, lateralizing and localizing temporal lobe seizures. In this paper, we review the EEG characteristics of temporal lobe epilepsy (TLE). Several "non-standard" electrodes may be needed to further evaluate the EEG localization. Ictal EEG recording is a major component of preoperative protocols for surgical consideration. Various ictal rhythms have been described including background attenuation, start-stopstart phenomenon, irregular 2-5 Hz lateralized activity, and 5-10 Hz sinusoidal waves or repetitive epileptiform discharges. The postictal EEG can also provide valuable lateralizing information. Postictal delta can be lateralized in 60% of patients with TLE and is concordant with the side of seizure onset in most patients. When patients are being considered for resective surgery, invasive EEG recordings may be needed. Accurate localization of the seizure onset in these patients is required for successful surgical management.RÉSUMÉ: Caractéristiques électroencéphalographiques de l'épilepsie temporale. L'électroencéphalographie (EEG) est un outil important pour le diagnostic, la latéralisation et la localisation de l'épilepsie temporale (ET). Dans cet article, nous revoyons les caractéristiques électroencéphalographiques de l'épilepsie temporale. Plusieurs électrodes « non-standard » peuvent être nécessaires pour une évaluation plus poussée de la localisation EEG. L'enregistrement EEG ictal est une composante importante des protocoles préopératoires pour des motifs chirurgicaux. Différents rythmes ictaux ont été décrits, dont l'atténuation du rythme de fond, le phénomène départ-arrêt-départ, une activité latéralisée irrégulière à 2-5 Hz et des ondes sinusoïdales à 5-10 Hz ou des décharges épileptiformes répétitives. L'EEG postictal peut également fournir de l'information précieuse pour la latéralisation. L'activité delta postictale peut être latéralisée chez 60% des patients atteints d'ET et concorde avec le côté du début de la crise chez la plupart des patients. Quand les patients sont évalués en vue d'une résection chirurgicale, des enregistrements EEG effractifs peuvent s'avérer nécessaires. Le succès de la chirurgie repose sur la l...