Video-EEG telemetry can be a crucial tool for neurologists experienced in epilepsy when diagnosing seizure disorders.

We retrospectively reviewed the charts of 121 patients consecutively admitted to our epilepsy-monitoring unit (VET) during the period of 01 July 2001 to 31 December 2002. We excluded patients with a confirmed diagnosis of epilepsy who were admitted for invasive pre-surgical monitoring. Medical records were reviewed to collect demographic and clinical information that lead to the initial referral for VET by neurologists with expertise in epilepsy or by an epileptologist. We identified 29 patients (24%), whose diagnosis changed after VET. Their seizure duration ranged from 1 to 46 years. A diagnosis of epileptic seizures (ES) was made in four of the patients who were initially felt to have nonepileptic seizures (NES). The diagnosis of NES was made in 22 patients who were initially felt to have ES. All of these 29 patients had failed at least two or more antiepileptic drugs (AEDs). A misclassification of epilepsy syndrome was found in three patients. Eleven of the NES patients had risk factors that would increase the likelihood of ES, including significant head injury (n=6), febrile seizures (n=2), meningioencephalitis (n=2), and tumours (n=1). Four of these 11 patients had abnormal interictal EEGs. We conclude that VET is crucial in establishing a diagnosis in patients with seizures. Without VET, patients can be misclassified or receive ineffective treatment, even when being treated by specialists in epilepsy. Thus, VET, can help facilitate the most appropriate type of therapy in difficult to control patients.