Purpose: The aim of this study was to examine the impact of clinical variables, particularly age at onset of epilepsy, on intellectual function in a group of children with temporal lobe epilepsy (TLE).
Methods: We reviewed the preoperative neuropsychological test results of 79 children with unilateral TLE who subsequently underwent surgical resection. The impact of age at onset and duration of epilepsy, pathology type, and side of resection on full-scale intelligence quotient (IQ) scores was examined.
Results: Intellectual dysfunction (defined as IQ < 79) was present in 57% of children, and age at onset of epilepsy was the best predictor of intellectual function. Children with epilepsy onset in the first year of life had a particularly high incidence of intellectual impairment (82.4%).
Conclusion: These data suggest a critical period during the first year of life for the subsequent development of intellectual abilities and highlight the importance of early treatment in this population.