Carotid Cavernous Fistula Treatment via Flow Diversion: A Systematic Review of the Literature

Background: Carotid cavernous fistulas (CCFs) are pathologic connections between the carotid arteries and the cavernous sinus and have been classically treated with endovascular coil embolization, although flow diverters have been used for treatment successfully multiple times. The aim of this study is to systematically review the literature for efficacy of flow diverters in treating CCFs.

Methods: A systematic review was conducted using the PRISMA guidelines. PubMed, PubMed Central, Cochrane Library, and Embase databases were searched. Combinations and variations of "carotid cavernous fistula," "flow diversion," "pipeline embolization device," "Surpass," "Silk," "p64," "FRED," and "flow redirection endoluminal device" in both AND and OR configurations were used to gather relevant articles. Citations of included articles from the systematic review were also screened for possible inclusion as a part of manual review. Included studies were full-text publications written in English that had patients with diagnosed CCFs and treatment with flow diversion.

Results: Eighteen full-text publications were relevant to this systematic review. A total of 41 patients underwent flow-diverting therapy alone or in conjunction with coil embolization, liquid embolization, and/or stenting for treatment of a diagnosed CCF. Twenty-nine patients (70.7%) needed 1 procedure alone, 11 patients (26.8%) required a second procedure, and 1 patient (2.4%) required a third procedure. Six patients (14.6%) had lasting symptoms despite intervention; however, all 41 patients had clinical improvement compared with initial presentation. Flow diversion was a useful solitary treatment or adjunctive treatment in all patients.

Conclusions: Flow diversion is a useful adjunct in combination with coil embolization for the treatment of CCFs but long-term outcomes remain to be seen.