Neuropsychological outcome of anterior temporal lobectomy

It is found that 77% of the neuropsychological measures remained unchanged following anterior temporal lobectomy, and only the area of memory/learning showed more cognitive loss than gain, and the areas of novel problem-solving ability showed the most improvement.

Abstract

Reviews of the literature have suggested that, following anterior temporal lobectomy (ATL) for treatment of medically intractable epilepsy, most cognitive functions remain unchanged, some exhibit a relative loss compared to preoperative levels, and some cognitive functions improve. The purpose of this investigation was to identify more precisely the nature and degree of this postoperative cognitive stability, loss, and gain. Thirty-eight patients undergoing ATL received an extensive neuropsychological evaluation both preoperatively and 6 months postoperatively. Utilizing an operational definition of neuropsychological test change that was hypothesized to be sensitive to performance alterations of probable clinical significance, we found that 77% of the neuropsychological measures remained unchanged following ATL. Of the cognitive change that occurred, 58% of the changes reflected significant cognitive improvement, whereas 42% of the changes reflected relative cognitive declines. Specific results are presented in regard to nine cognitive domains (psychometric intelligence, academic achievement, language function, visuoperceptual and visuospatial ability, memory and learning ability, problem-solving skills, sensorimotor ability, auditory-perceptual function, and complex attention/concentration skills). Only the area of memory/learning showed more cognitive loss than gain, and the area of novel problem-solving ability showed the most improvement. The clinical and theoretical implications of these findings are discussed.