Spontaneous regression of large bilateral basal ganglia arteriovenous malformations.

The complete or partial spontaneous regression of large arteriovenous malformations (AVM) is very rare [1-5]. In most cases, a hemorrhagic event or surgical manipulation will have contributed to the thrombosis of the AVM [2, 3]. We report here a patient with large bilateral basal ganglia AVMs who presented with headaches. She was neurologically intact and has remained so for 1 0 years. The patient recently developed new bifrontal headaches that were not associated with hemorrhage or ischemia as revealed by MR imaging. An angiogram demonstrated near complete regression of the large AVMs. This case is unique because of the bilateral location of the AVMs in the basal ganglia as well as their spontaneous regression.