Proposal of venous drainage-based classification system for carotid cavernous fistulae with validity assessment in a multicenter cohort

Abstract

BACKGROUND: Carotid cavernous fistulae (CCFs) are most commonly classified based on arterial supply. Symptomatology and treatment approach, however, are largely influenced by venous drainage. OBJECTIVE: To propose an updated classification system using venous drainage. METHODS: CCFs with posterior/inferior drainage only, posterior/inferior and anterior drainage, anterior drainage only, and retrograde drainage into cortical veins with/without other drainage channels were designated as types 1, 2, 3, and 4, respectively. CCFs involving a direct connection between the internal carotid artery and cavernous sinus were designated as type 5. This system was retrospectively applied to 29 CCF patients. RESULTS: Our proposed classification was significantly associated with symptomatology (P