Neuro-Ophthalmic Manifestations of Carotid Cavernous Fistulas: A Systematic Review and Meta-Analysis

Abstract

Carotid-cavernous fistulas (CCFs) are pathologic, arteriovenous communications between the carotid artery and cavernous sinus. They cause various complex neuro-ophthalmic symptoms by shunting the flow of arterial blood into the venous system. In this study, a systematic review is conducted on the neuroophthalmic presentations associated with CCFs. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses 2020 guidelines were followed during the systematic review. We searched PubMed, Scopus, and Web of Science from inception to December 31, 2023. Articles written in English on patients with confirmed CCFs reporting clinical features, diagnostic modalities, treatment approaches, and outcomes were included. Abstracted data included demography, clinical presentations, venous flow dynamics, trauma history, investigative methodology, approaches to treatment, and outcomes. Overall, 33 studies with a total number of 403 patients were included. The mean age at presentation was 42.99 years for patients with direct CCFs and 55.88 years for those with indirect CCFs. Preponderance was observed in male patients with direct CCFs, constituting 51.56%, while females predominated in those with indirect CCFs, at 56.44%. The clinical symptoms in all patients with CCFs were proptosis in 58 cases (14.39%), conjunctival congestion in 29 patients (7.20%), diplopia in nine patients (2.23%), vision blurring in four patients (0.99%), eyelid swelling in five patients (1.24%), pain in the eye in three patients (0.74%), and an upper lid mass in one patient (0.25%). Endovascular treatments, including coil and Onyx embolization, have been effective in relieving clinical symptoms and arresting the progression of these symptoms. In conclusion, the common clinical features in CCFs usually underline proptosis, congestion, and diplopia, necessitating a comprehensive neuro-ophthalmological review. Prompt identification of the symptoms of blurred vision is crucial to avoid permanent damage. Lid swelling, ocular pain, and an upper lid mass are less common but equally essential presentations for comprehensive evaluation. The recognition of these variable presentations is essential not only for timely intervention but also for the improvement in patient outcomes, thus emphasizing the role of clinician awareness in managing CCF cases.