Clinical characteristics of dural arteriovenous fistula.

Intracranial dural arteriovenous fistula (DAVF) is an uncommon neurosurgical condition; in particular, it has been infrequently reported in Korea. To understand the general clinical characteristics of DAVFs, the authors reviewed 53 cases and analyzed factors affecting DAVF hemorrhage of and treatment outcome. Since 1980 we have encountered 480 pial and 53 DAVFs, a ratio of 9.1 to 1. The age of these patients ranged from 1 month to 71 years, the most common being in the 6th decade, and females exceeded males by 1.65 to 1. All lesions except three were single, and symptoms were related to location and the venous drainage pattern. The most common location was the cavernous sinus, accounting for about 64% of cases, with the result that the most common clinical symptoms of DAVFs were ocular, namely proptosis and chemosis. The next was tinnitus also found in transverse-sigmoid sinus DAVFs. Intracranial hemorrhage was seen in eight cases,(15%) the primary cause of hemorrhage was retrograde intracranial venous drainage (P=0.017), and one hemorrhage was observed in cases with no intracranial venous drainage. Intracranial hemorrhage was more frequently in transverse-sigmoid than cavernous sinus DAVFs (P=0.049), and this proved to be so even where there was intracranial venous drainage. However, two of 34 patients with cavernous DAVFs became blind in one eye, demonstrating that in such patients, the clinical course could be aggressive. Thirteen patients were treated conservatively. The conservative treatment group was comprised of 13 patients, two of three patients with transverse-sigmoid sinus DAVF expired, and 7 of 10 with cavernous sinus DAVF experienced a clinical improvement or cure. Surgical excision was performed in only two patients. A total of 39 patients underwent embolization; clinical cure was achieved in 13, improvement of symptoms in 12, an unchanged or aggravated result occurred in 9, one died, and four were lost to follow up. During intervention, there was one hemorrhagic complication, owing to obstruction of the venous outflow with embolic materials. In this study, the most common location of DAVFs was the cavernous sinus. The cortical venous drainage remains the primary determinant of intracranial hemorrhage. Common indications for treatment include hemorrhage and neurological deficit. Endovascular treatment is preferred in the majority of cases except tentorial DAVF. The goal of embolization in cavernous DAVF is the alleviation of symptoms, not angiographic cure. But transverse-sigmoid sinus DAVF with venous restriction and leptomeningeal drainage should be treated aggressively.