Endovascular management of craniospinal arteriovenous fistula causing steal syndrome in neurofibromatosis type 1: a case report.

Background: Neurofibromatosis type 1 (NF1) is an autosomal dominant genetic disorder. It primarily involves cutaneous, neurological and skeletal systems, with vascular involvement being relatively uncommon. Among the reported vascular manifestations, stenoses, aneurysms, and arteriovenous fistulas (AVFs) are infrequent but potentially serious complications. Their manifestation with cerebral steal syndrome is of even lower prevalence. Case Description: We report a case of a 52-year-old female with known NF1 who presented with progressive headache, transient episodes of right-sided weakness and speech problems. Total selective digital subtractive cerebral angiography revealed AVF of the left occipital region, primarily supplied by a large longitudinal defect in the V4 segment of the left vertebral artery, with additional feeders from the left occipital and ascending cervical arteries. A vertebrobasilar "steal" phenomenon was observed, with retrograde filling of the basilar circulation via the carotid system. Given the progressive symptoms and hemodynamic compromise, the patient underwent endovascular embolization using balloon catheters, detachable coils and Onyx 18 liquid embolic agent. The procedure was uneventful, with successful devascularization of the AVF and improved perfusion to the surrounding tissue. Post procedural recovery was favorable, with disappearing of existed symptoms. Conclusions: AVFs are rare in patients with NF1, and their pathogenesis is not fully understood. Steal syndrome occurs when high flow vascular malformations divert blood from surrounding brain parenchyma, leading to ischemic symptoms. Our case contributes to the limited literature on NF1-associated AVF and supports early neurovascular imaging in symptomatic individuals. Awareness of this rare vascular complication in NF1 is crucial for timely diagnosis and management.