Fig. 2

Five types of venous draining of cavernous fistula. a Arterial blood is drained to facial vein from cavernous sinus through superior ophthalmic vein and angular vein; b arterial blood is drained to superior sagittal sinus from cavernous sinus through trolard frontal parietal anastomotic vein. c arterial blood is drained to basilar vein from cavernous sinus through an anastomotic vein, and together with Vein of Galen , drained to straight sinus. d arterial blood is drained to internal carotid vein from cavernous sinus through superior petrosal vein, inferior petrosal vein, basilar vein and plexus pterygoideusta. e A mixed type: Two kinds of draining together of the four mentioned above. 1. cavernous sinus; 2. basilar vein; 3. straight sinus; 4. superior petrosal sinus; 5. inferior petrosal sinus; 6. plexus pterygoideusta’7. Trolard frontal parietal anastomotic vein; 8.superior sagittal sinus; 9. superior ophthalmic vein; 10. facial vein