Basic concepts of functional magnetic resonance imaging and arteriovenous malformations.

Cortical mapping is an important adjunct to the workup of patients with arteriovenous malformation (AVMs) near eloquent cortical regions. Task activation imaging can be performed that clearly identifies primary cortical regions. Although current methods require considerable postprocessing, advances in hardware and software will likely make functional MR imaging a routing examination before surgical resection of AVMs in the near future.