Recurrent subdural hematomas in the setting of CSF-venous fistulas: illustrative case.

backgroundCSF leaks can cause resistant subdural hematomas (SDHs). Spinal CSF-venous fistulas (CVFs) are a rare cause of this problem. A better understanding of this phenomenon would guide decision-making when planning treatment and follow-up. The authors reviewed a case of a recurrent right-sided SDH secondary to a previously unknown CVF. In addition, a systematic review was conducted in accordance with PRISMA guidelines for previously documented cases. OBSERVATIONS: Seven cases were found in the literature, with ours representing the eighth case of recurrent SDH due to a CVF-induced CSF leak. The mean age was 60 years, and 75% of patients were male. Common initial presentations included headache (100%), tinnitus (75%), and nausea/vomiting (50%). All patients were treated with Onyx embolization, with 62.5% also receiving middle meningeal artery (MMA) embolization. All patients experienced improvement of SDH size after treatment, with 62.5% demonstrating complete resolution. LESSONS: Spinal CVFs are a rare but serious cause of CSF leaks and recurrent SDHs. Cases typically occur in men around 60 years of age, and common symptoms include headache, tinnitus, and nausea/vomiting. Treatment with CVF embolization results in improvement or resolution of SDH burden, while the role of MMA embolization in the treatment of these SDHs remains unclear. https://thejns.org/doi/10.3171/CASE25338.