Diagnostic testing of seizure disorders

Although a thorough history and physical examination remain the basis for the evaluation of patients with a possible seizure disorder, electroencephalography (EEG) is a necessary extension of the neurologic examination. Most patients also require a magnetic resonance imaging (MRI) scan to identify a potentially epileptogenic lesion. This article reviews the technical considerations, common findings, and potential pitfalls related to the use of EEG and MRI. Adjunctive tests such as ambulatory EEG, video/EEG, positron emission tomography, single photon emission computed tomography, and serum evaluation also are discussed for use in specific circumstances.