Clinical Characteristics and Management Considerations of Craniocervical Junction Arteriovenous Fistulas With Subarachnoid Hemorrhage: A Multicenter Study

BACKGROUND AND OBJECTIVES: Craniocervical junction (CCJ) arteriovenous fistulas (AVFs) presenting with subarachnoid hemorrhage (SAH) are rare conditions, with the optimal timing and approach to treatment still debated among neurosurgeons. The aim of this study was to characterize CCJ AVF–related SAH and determine appropriate surgical timing in a multicenter study. METHODS: Data from 111 consecutive patients with CCJ AVF, including 51 with SAH, were collected from 29 centers across Japan. The vascular anatomy, diagnosis, treatment, surgical timing, and clinical outcomes were analyzed. Binary logistic regression was used to identify risk factors for complications. RESULTS: The mean age of the patients was 67 years (range, 33-85 years), with 36 male patients and 15 female patients. Notably, a high percentage of patients (84%) presented with mild SAH (World Federation of Neurosurgical Societies grade I or II). Rebleeding and symptomatic vasospasm each occurred in 2% of cases. Initial treatments included direct surgery (n = 38), endovascular treatment (n = 10), and combined therapy (n = 3). Of the 51 patients, 17.6% (9/51) underwent acute (within 3 days of onset), 17.6% (9/51) subacute (within 4-14 days), and 64.7% (33/51) delayed procedures (after 15 days). Our study revealed a higher rate of complications, especially ischemic complications ( P = .028), in patients who underwent acute surgery than in those who underwent delayed procedures. Endovascular treatment required retreatment in 60% (6/10) of cases, whereas direct surgery did not necessitate retreatment. The final modified Rankin Scale scores did not differ based on surgical timing. CONCLUSION: CCJ AVF–related SAH is often mild, as evidenced by a high proportion of patients with low-grade World Federation of Neurosurgical Societies scores and a low rate of rebleeding/vasospasm. In contrast to intracranial aneurysmal SAH, our results do not support acute surgical intervention as the preferred management for patients with CCJ AVF–related SAH. Through delayed surgery, clinicians can avoid ischemic complications and improve patient outcomes.