Epilepsy imaging study guideline criteria: commentary on diagnostic testing study guidelines and practice parameters.

Recognition of limited economic resources, as well as potential adverse effects of "over testing," has increased interest in "evidence-based" assessment of new medical technology. This creates a particular problem for evaluation and treatment of epilepsy, which are increasingly dependent on advanced imaging and electrophysiology, since there is a marked paucity of epilepsy diagnostic and prognostic studies that meet rigorous standards for evidence classification. The lack of high quality data reflects fundamental weaknesses in many imaging studies but also limitations in the assumptions underlying evidence classification schemes as they relate to epilepsy, and to the practicalities of conducting adequately powered studies of rapidly evolving technologies. We review the limitations of current guidelines and propose elements for imaging studies that can contribute meaningfully to the epilepsy literature.