Occult vascular malformations and seizures.

Occult vascular malformations are frequently associated with intractable seizures and are a common cause of lesional epilepsy. MR imaging can identify and characterize these lesions with accuracy. The presurgical evaluation must be tailored to the individual patient's presentation and circumstances. Surgical results following lesionectomy plus corticectomy may be slightly superior to lesionectomy alone, but the overall prognosis is excellent.