Cerebral venous malformations.

Although cerebral venous malformations have been reported to cause epilepsy, progressive neurological deficits, and hemorrhage, their clinical significance remains controversial. In an attempt to clarify the natural history of the lesion and suggest an appropriate management strategy, the authors review their experience with 30 patients. In four patients with cerebellar venous angioma, an acute episode of ataxia was documented. The coexistence of a cavernous malformation was pathologically confirmed in the two patients who underwent surgery for bleeding presumed caused by the venous angioma. Infarction was shown in two patients and a tumor in two others. Follow-up periods ranged between 18 and 104 months, with only five patients symptomatic at the time of this report. Rebleeding had not occurred, nor had acute episodes of neurological dysfunction been documented. This clinical experience suggests that a venous malformation is frequently associated with other, more symptomatic conditions and is often erroneously identified as the source of the symptoms. Because the nature of the relationship between the venous malformation and the allied conditions remains ambiguous, it is recommended that patients harboring a "symptomatic" venous malformation undergo high-field magnetic resonance imaging to rule out underlying pathology, and that any such pathology be treated independently of the venous malformation.