Magnetoencephalography/magnetic source imaging as part of the preoperative evaluation of patients with drug-resistant epilepsy may be considered medically necessary when standard techniques, such as magnetic resonance imaging and electroencephalogram, do not provide satisfactory localization of epileptic lesion(s) (see Policy Guidelines).
Magnetoencephalography/magnetic source imaging for the purpose of determining the laterality of language function, as a substitute for the Wada test, in patients being prepared for surgery for epilepsy, brain tumors, and other indications requiring brain resection, may be considered medically necessary.
Magnetoencephalography/magnetic source imaging is considered investigational for all other indications.
