Syncope is often difficult to distinguish from a seizure because both can present clinically with a transient loss of consciousness 1 . Published studies have found that the electroencephalogram (EEG) is of low diagnostic yield when the clinical diagnosis is syncope [2][3][4][5] . Reviews state that EEGs should not be performed routinely in cases of suspected syncope unless there has been a witnessed seizure 6 , there is a history of prior seizures 7,8 , or there are "symptoms suggestive of a seizure" 7,9 . Electroencephalograms ordered by a neurologist might be expected to have a higher diagnostic yield because most neurologists are experienced in evaluating patients with syncope and seizures, and presumably would only refer a patient with suspected syncope for an EEG if there was something ABSTRACT: Background: Prior studies have shown that the electroencephalogram (EEG) is of low diagnostic yield in the evaluation of syncope but have not looked at the yield according to referring physician specialty. The goals of this study were to determine if the yield of the EEG is higher when ordered by neurologists and whether EEGs with abnormal findings resulted in any significant change in patient management. Methods: We retrospectively reviewed the records of the EEGs requested for a clinical diagnosis of syncope, convulsive syncope, loss of consciousness, or falls from 2003 to 2007 at our institution. We obtained further information from the medical record of patients with an abnormal EEG. Results: Of 517 EEGs meeting our inclusion criteria, only 57 (11.0%) were read as abnormal. No EEG was positive for epileptiform activity and only 9 (1.6%) showed potentially epileptic activity. EEGs ordered by neurologists did not have a higher yield compared to non-neurologists. Five abnormal EEGs resulted in further investigations being ordered. One patient was ultimately started on phenytoin. Conclusions: EEGs requested for the evaluation of patients with suspected syncope have an extremely low diagnostic yield and do not significantly alter the management of the patients, regardless of the specialty of the referring physician.
RÉSUMÉ: L'EEG chez les patients suspects de syncope : les EEG demandés par les neurologues donnent-ils un meilleur rendement? :Contexte : Des études antérieures ont montré que l'électroencéphalogramme (EEG) offre un rendement diagnostique faible dans l'évaluation de la syncope, mais ces études n'ont pas examiné le rendement selon la spécialité du médecin qui réfère le patient. Les buts de cette étude étaient de déterminer si le rendement de l'EEG est plus élevé quand il est demandé par un neurologue et si les EEG dont les résultats sont anormaux entraînaient des changements significatifs dans le traitement du patient. Méthodes :Nous avons revu de façon rétrospective les dossiers des EEG demandés de 2003 à 2007 dans notre institution à cause d'un diagnostic clinique de syncope, de syncope convulsive, de perte de conscience ou de chute. Nous avons tiré des informations complémentaires des dossiers médicaux...