Basal cerebral venous drainage from cavernous sinus dural arteriovenous fistulas

Introduction  This study aimed to define the patterns of basal cerebral venous drainage (BCVD) from cavernous sinus dural arteriovenous fistulas (CSDAVFs). Materials and methods  Forty sets of selective angiographic data from 36 patients with spontaneous CSDAVFs (age range, 53–79 years) were retrospectively analyzed for their drainage patterns. Three types of BCVD were observed, i.e., superolateral type, BCVD via the deep middle cerebral vein or uncal vein; posterolateral type, BCVD via the superior petrosal sinus and petrosal vein; and posteromedial type, BCVD via the bridging vein and the anterior pontomesencephalic vein. MR images and/or 3D-DSA images were also reviewed when available. Results  BCVD from CSDAVF was found in 12 patients (30%), and the other drainage routes included the superior ophthalmic vein in 25 (63%), the inferior petrosal sinus in 17 (43%), the superficial middle cerebral vein in 17 (43%), intercavernous sinus in 15 (38%), the superior petrosal sinus in seven (18%), and pterygoid plexus in two (5%), respectively. In 12 patients with BCVD, superolateral type was found in four (33%), posterolateral type in five (42%), and posteromedial type in seven (58%). Four cases of posteromedial type were associated with other types of BCVD. Conclusion  CSDAVFs are often associated with BCVD via three different pathways. The posteromedial type via the bridging vein is the most frequent type of BCVD.