Use of positron emission tomography for the evaluation of epilepsy.

After a brief introduction to the theoretic aspects of positron emission tomography, four areas of positron emission tomography research are discussed with an emphasis on current concepts and future directions. The use of positron emission tomography as a tool for the localization of the pathologic brain region and as a predictor of surgical outcome in focal epilepsy is reviewed and compared with the sensitivity, specificity, and outcome predicted by other neuroimaging techniques. Research on positron emission tomography measures of regional metabolism, bloodflow, and neuroreceptors is reviewed from the perspective of epileptic pathophysiology with a special emphasis on elucidative integrative neural circuits involved in epileptic spread and termination. A brief review and discussion of the use of positron emission tomography for the understanding of potential neural reorganization of cognitive processes in epilepsy follows. In the final section, an overview of recently developed methods of positron emission tomography data analysis with a focus on application to research questions in epilepsy is presented.