2 UNUSUAL CASES OF MULTIPLE DURAL ARTERIOVENOUS-FISTULAS

OBJECTIVE AND IMPORTANCE: Two patients with dural arteriovenous fistul as involving the transverse sinus and superior sagittal sinus are desc ribed, with a focus on the unique type of venous drainage of the fistu la. CLINICAL PRESENTATION: Both patients presented with papilledema an d progressive visual disturbance. Angiography and magnetic resonance i maging showed that the fistulas involving the superior sagittal sinus had a dilated venous channel, separate from the sinus lumen, located w ithin the wall of the sinus. INTERVENTION: Transvenous embolization of the venous channel of the fistula, proximal to its drainage into the superior sagittal sinus, resulted in closure of the fistula and restor ation of the superior sagittal sinus function. The clinical symptoms w ere reversed; the symptoms are believed to have reflected venous hyper tension in the superior sagittal sinus, resulting from the shunted flo w and interfering with normal venous drainage. CONCLUSION: This unique type of dural arteriovenous fistula may be a variant, occurring in th e developmental process of the fistula. It is significant clinically b ecause transvenous embolization can be used to close the fistula and r estore sinus function.