Flow diversion in direct carotid-cavernous fistula refractory to multiple coil embolizations: case report and review of the literature

Objectives: Direct carotid-cavernous fistulas are high-flow abnormal connections between the carotid artery and cavernous sinus, which are associated with significant morbidity and mortality if left untreated. In addition to endovascular coil embolization, there is an evolving role for alternative stand-alone or adjunctive treatment approaches. We describe a case of flow diversion as an adjunctive treatment approach in a treatment-resistant direct carotid-cavernous fistula and review the literature on the use of flow diversion in this clinical context.

Materials and methods: We describe the clinical course, imaging findings, and outcome of a patient who developed a traumatic carotid-cavernous fistula requiring multiple interventions. We also performed an updated literature review of all published cases of flow diversion use in the treatment of direct CCFs.

Results: Our patient achieved angiographic cure and significant improvement in symptoms at 6-month follow-up. A total of 53 cases of flow diversion use in direct carotid-cavernous fistulas were identified from a literature search. In one third of cases, flow diversion was used as a stand-alone treatment modality. Angiographic resolution was achieved in 90% of cases at a median follow-up duration of 6 months. One half of reported cases had complete resolution of symptoms and a further third noted clinical improvement in at least some of their symptoms.

Conclusions: There is an emerging role for flow diversion as a safe and effective stand-alone or adjunctive treatment option for direct carotid-cavernous fistulas. Our case further supports a role for flow diversion in treatment-resistant fistulas with high-risk features. As treatment approaches continue to evolve, prospective, randomized data will be needed to establish the role of flow divertors in the hierarchy of available treatments for carotid-cavernous fistulas.