ABSTRACT
A case of unruptured arteriovenous malformations (AVMs) presenting benign intracranial hypertension is reported. A 14-year-old male suffered from headache and papilledema. Intracranial pressure was 260 mmH2O. Unenhanced CT demonstrated no evidence of hemorrhage or hydrocephalus. Angiogram demonstrated a large AVM in the left temporal lobe supplied by the left posterior cerebral artery and left middle cerebral artery. It drained into the transverse sinus. Surgical excision of the AVM eliminated the headache and papilledema. AVM causes hemorrhage in 50% of cases, seizure in 30%, and other focal neurological deficits in 20%. Benign intracranial hypertension is an uncommon effect of unruptured AVMs. Only 13 cases have been reported in the literature. Benign intracranial hypertension associated with unruptured AVMs occurs in young patients with high flow AVMs that drain into the major sinus. The mechanism of intracranial hypertension associated with unruptured AVM is unknown. However, there are several possible mechanisms of intracranial hypertension associated with unruptured AVMs. The arterial blood shunting into a major sinus impedes venous return from the surrounding brain. That causes the increase of cerebral blood volume and the elevation of sinus pressure. This mechanism would reduce CSF absorption and would increase intracranial pressure. Pharmacological therapy is ineffective in controlling intracranial hypertension. Surgical excision of AVM effectively reduced intracranial hypertension. Thus, surgical excision of AVMs, if it can be done with low risk, is the treatment of choice to decrease intracranial hypertension in patients with unruptured cerebral AVMs.
