Long-Term Outcomes of Endovascular Treatment of Indirect Carotid Cavernous Fistulae: Superior Efficacy, Safety, and Durability of Transvenous Coiling Over Other Techniques

BACKGROUND Endovascular surgery is the first-line treatment for indirect cavernous carotid fistulae (CCFs). This study compares multiple treatment techniques. OBJECTIVE To compare endovascular techniques for indirect CCF treatment. METHODS Retrospective analysis was performed of prospectively maintained records at 4 centers, identifying patients undergoing indirect CCF embolization. Demographics, symptoms, and lesion characteristics were recorded. Medical records were reviewed for changes in symptoms, delayed complications, and angiographically proven recurrence. Univariate and multivariate analyses were performed to identify impacts of the above characteristics on outcomes. RESULTS Sufficient records were available for 267 patients treated between January 1987 and December 2016. Obliteration was achieved in 86.5% patients, occurring in 86.9% of exclusively transvenous treatments and 79.5% of other treatments. Obliteration rates were highest following transvenous embolization using coils compared to all other materials (likelihood ratio [LR] 5.0, P=.024). Complications were less common with coil embolization compared to other materials (LR 0.070, P<.001). Embolization with liquid embolics resulted in higher complication rates (LR 10.2, P=.002), although risk was reduced when used in conjunction with coils. Angiographically confirmed recurrence was more common following embolization with polyvinyl alcohol (LR 9.9, P=.004) and when multiple embolic agents were used (LR 6.6, P=.018). Delayed development of symptoms following embolization was less common following embolization with coils (LR 0.20, P=.030) and more common following embolization with liquids (LR 6.5, P=.014). CONCLUSION To treat indirect CCFs, transvenous coil embolization is the safest and most effective technique. Liquid embolics are less effective and have more complications and should be carefully considered only in extenuating circumstances.