The role of neuropsychological assessment in the presurgical evaluation of epilepsy surgery candidates

Abstract

This chapter discusses the role of presurgical neuropsychological assessment in identifying functional deficits in epilepsy surgical candidates and forecasting cognitive outcome following surgery. Neuropsychological assessment is a well-supported method of obtaining information regarding an individual patient's cognitive strengths and weaknesses. Data from these assessments are important in the preoperative evaluation of epilepsy surgical candidates because they: (1) provide an indication of the extent of the functional-deficit zone, and (2) help predict cognitive outcome following surgery. The sensitivity of neuropsychological assessment to subtle deficits that can be found in epilepsy patients might be enhanced by adopting more theoretically derived novel measures, and employing likelihood or odd ratio analyses to determine the cutoff scores for optimal identification of patient groups. The preoperative neuropsychological assessment provides data that are discordant from the remaining investigations and suggest that the functional-deficit zone extends beyond the epileptogenic zone. These data can be important in determining the need for further investigations and may have prognostic significance. The preoperative evaluation provides an essential baseline assessment, against which changes in function can be compared following surgical resection. The information from these evaluations is crucial in identifying the patients at risk for sustaining cognitive declines following the surgery.