Abstracts

The objectives of this study were to investigate the EEG profile in a group of patients with clinical diagnosis of idiopathic generalized epilepsy (IGE) followed in a tertiary Hospital and to evaluate the contribution of the records for diagnosis and management of these patients. We retrospectively studied clinical and EEG features of 180 consecutive patients with IGE. Eighty patients were diagnosed with juvenile myoclonic epilepsy (JME), 35 had absence epilepsy (AE), 13 had generalized tonic-clonic seizures on awakening (GTCS-A), 28 had generalized tonic-clonic seizures only (TCS) and 24 had adult onset idiopathic generalized epilepsy (AIGE). The EEGs were classified in typical (synchronous generalized spike or polyspike and wave discharges with normal background), atypical (with clear focalities or asymmetries) and normal. A total of 493 EEG exams were analyzed. The first EEG was normal in 45% of the 180 patients and only 33% had typical abnormalities. AE had a higher proportion of typical exams and needed less sequential exams to register a typical abnormality compared to the other groups. By contrast, the serial EEG profile of TCS and AIGE showed a higher proportion of normal and atypical EEG findings. These findings support previous recommendations that IGE patients should be treated with appropriate therapy based on clinical history. Waiting for a typical abnormal EEG pattern can generate an unacceptable delay in the correct diagnosis and treatment of these patients. In patients with long term epilepsy the diagnosis may be difficult. Furthermore, serial EEGs can help to elucidate the syndromic diagnosis, especially in patients with TCS and AIGE. (Supported by CAPES, FAPESP.)