Vascular malformations and intractable epilepsy: outcome after surgical treatment

To review our recent experience with surgical treatment of patients with vascular malformations and intractable partial epilepsy.

We retrospectively studied 20 consecutive Mayo patients who had undergone surgical treatment of medically refractory partial epilepsy and had cerebral vascular malformations.

Seizures were the initial symptom in all 13 female and 7 male patients, none of whom had a history of a symptomatic intracerebral hemorrhage. Magnetic resonance imaging (MRI) or pathologic examination, or both, indicated the presence of remote hemorrhage associated with the vascular lesion in 18 patients. MRI disclosed 36 vascular malformations (32 cavernous and 4 arteriovenous malformations) in the 20 patients. MRI was more sensitive and specific than computed tomography for their detection and characterization. The operative strategy in all patients included complete resection of the vascular malformation. A modified Engel classification (based on four classes) was used to determine the outcome of seizures.

Postoperatively, 15 patients were free of seizures, and 3 patients had at least a 90% decrease in number of seizures. Only two patients had an unfavorable outcome. Neither the age at onset of seizures nor the duration of seizures seemed to affect the outcome. The site of the vascular malformation was less important than precise correlation between the site of onset of seizure activity and the corresponding vascular malformation. The presence of coexistent ipsilateral atrophy of the hippocampal formation should be sought, and the operative strategy should be appropriately modified.

In the absence of dual pathologic conditions, lesionectomy can yield a seizure-free outcome in patients with intractable partial epilepsy and cerebral vascular malformations.