Dural Arteriovenous Fistulas at the Petrous Apex

Dural arteriovenous fistulas (DAVFs) at the petrous apex are rare but may cause subarachnoid hemorrhage (SAH) or severe brainstem edema. This study aimed to summarize their clinical features and discuss the classification.

During a 15-year period, 64 consecutive patients with DAVF at the petrous apex were reviewed. According to their angioarchitecture, these cases were classified as follows: type I, no venous ectasia (48.4%); type II, venous ectasia but with normal vein proximal to the fistula (29.7%); and type III, venous ectasia at the site of the fistula (21.9%).

There were 53 men and 11 women included. Presented symptoms were SAH in 8 patients (12.5%), nonhemorrhagic neurologic defects (NHNDs) in 53 patients (82.8%), and no symptoms in 3 patients (4.7%). There were 49 patients who received transarterial embolization, 8 patients who received microsurgery, and 7 patients who received embolization and microsurgery. Complications occurred in 9 patients (14.1%), including transient cranial nerve palsy (4.7%), rebleeding (6.3%), and respiratory failure (3.1%). Of the type I patients, 96.77% presented with NHNDs and 77.42% presented with infratentorial drainage. However, SAH occurred more often in type II (21.05%)/type III cases (28.57%), and most patients carried a supratentorial drainage (63.16% and 85.71%, respectively). In different types of DAVFs, the necessity for embolization combined with microsurgery (6.45% in type I, 10.53% in type II, 21.43% in type III) and the occurrence of rebleeding complications (0% in type I, 10.53% in type II, and 14.29% in type III) were varied.

Petrous apex DAVFs carried a high risk of embolization-related complications. Based on the vascular architecture, this classification may reflect their clinical features and provide some advice on the treatment of DAVFs at the petrous apex.