Flow diverter reconstruction for direct carotid– cavernous fistula: patient-level pooled analysis plus single-center experience

Introduction: Flow diverters (FDs) have emerged as a reconstructive, carotid-preserving treatment for direct (Barrow A) carotid–cavernous fistula (dCCF), but their angiographic efficacy, expected time to occlusion, and the clinical value of deploying multiple devices remain uncertain. Materials and methods: We performed a pooled individual-patient data analysis of 72 dCCFs treated with FD stents, with or without adjunctive embolization, including 64 cases from published reports and 8 from our institution. Primary outcomes were complete angiographic occlusion and time to oc­clusion; clinical improvement was a secondary outcome. Associations between FD count and outco­mes were assessed using Pearson’s and Spearman’s correlations, ordinary least squares regression, logistic regression, and chi-square testing. Results: FDs were the primary treatment in 47/72 cases, and FD alone was used in 31/72 (43%). Ad­junctive treatments included coils (n = 34), liquid embolic agents (n = 4), and covered stents (n = 2). Complete angiographic occlusion was achieved in 67/72 cases (93%), and clinical improvement was observed in 53/72 cases (73%). Among 62 cases with measurable timing, median time to occlusion was 105 days (range, 0–720), with approximately two-thirds occluding within 6 months. FD count was not associated with faster occlusion or improved clinical outcomes. Discussion: FD provides high rates of carotid-preserving cure in dCCF, but occlusion is often delayed, typically occurring over 3–6 months. Conclusion: Although FD monotherapy is unsuitable when immediate shunt closure is required, such as in cases of intracranial hemorrhage or cortical venous reflux, it may have an adjunctive role in select cases. FD count was not associated with reported outcomes.