Electroencephalographic profile of children attending a neurophysiology centre in Lagos, Nigeria

Author(s): Mohammed A Salisu, Idowu O Senbanjo

Background: Electroencephalography (EEG) is an important diagnostic tool for the evaluation of neurological disorders. There is a paucity of information about EEG recordings in Nigerian children. This study, therefore, aimed to describe the pattern and prevalence of EEG abnormalities among children referred for EEG assessment at a neurophysiology centre in Lagos, Nigeria. Methods: This was a prospective study carried out at a neurophysiology centre, Lagos, Nigeria. Consecutive 200 patients referred for EEG at a neurophysiology centre between 1st October, 2015-30th April 2016 were recruited into the study. Information was obtained on demographic, clinical presentation and EEG recordings. Results: The age of children ranges from 1-192 months with a median age of 42 (IQR 25-88) months. There were 128 males (64%) and 62 females (36%). Commonest clinical indications for making EEG request were seizure disorder (55%), cerebral palsy (24.5%) and febrile seizure (6.5%). EEG recording was abnormal in 161 (80.5%) children. There was a significantly high prevalence of abnormal epileptiform discharges in all cases with the exception of children with febrile seizures (p=0.002). The commonest abnormal epileptiform discharges were focal (70.2%). Others were generalized epileptiform activity (24.8%) and slow and diffuse waves suggestive of encephalopathies (5%). Ten (2%) children from the study population were diagnosed with absence seizure, Lennox-Gaustaut, and infantile spasm Conclusion: Secondary causes of seizure are an important contributor to seizure disorders in Nigerian children. The EEG is useful in the detection and classification of seizure types.