Abstracts

Rationale: Generalized epilepsy is composed of both IGE and SGE, and account for approximately 30% of the epilepsies with intermediary forms described. With IGE, at least 15% may be refractory to treatment with appropriate AEDs such as VPA and LTG. Absence, myoclonic, and generalized tonic-clonic seizures are the seizure types that comprise the IGEs. While most IGEs are readily controlled with treatment, we describe the breakdown of patients with IGE admitted to an EMU. Methods: Medical records from 1164 patients admitted to our EMU between 2004 and 2007 were retrospectively identified. 60 patients had uncontrolled seizures on admission with a final diagnosis of IGE. Ictal recordings were obtained in 38/60 to assist with treatment and were analyzed for electrographic onset and seizure type. Seizure type was defined according to the ILAE criteria1. Awake and asleep interictal and ictal EEG recording was performed on the XLTEK video-EEG telemetry monitoring system with at least 21 channels of electrodes placed in accordance with the International 10-20 system of electrode placement. Ictal tracings were reviewed at admission in light of the patient history including age of onset and seizure types, neurological examination, and neuroimaging in each case. Results: 1164 patients underwent video-EEG monitoring from 2004-2007, 719 (61.8%) received a definitive diagnosis of epilepsy, and 445 (31%) had non-epilepsy. Of those PWE, 555 (77%) patients had localization-related epilepsy and 104 (14%) had generalized epilepsy comprising 5.15% of the total population. Of patients with primary generalized seizures, 60/104 (57.7%) had IGE. Ictal recordings were obtained in 38/60 patients (63.3%) in addition to interictal recordings. The frequency of seizures recorded in 38 patients with IGE included 11 with absence seizures, 14 with myoclonic seizures, 21 with GTC seizures, and 2 not classified. Of the 38 patients with a final diagnosis of IGE and ictal recording, 13 were male and 25 were female with a mean age of 25.3 and 27.2 on a mean of 2.6 and 2.1 AEDs respectively. Final syndromic diagnoses were IGE NOS (24), JME (7), CAE (2), JAE (3), Panayiotopoulous syndrome evolving to IGE with GTC seizures (1), IGE/JME with concomitant LRE (1). Conclusions: IGE represents 5% of patients admitted for video-EEG for refractory seizures. GTC seizures are the most promient type of seizure in patients with IGE undergoing ictal recordings in an EMU. IGE NOS appears to be the principle syndromic type of IGE requiring video-EEG monitoring at a tertiary care epilepsy center.