Spinal dural arteriovenous fistula masquerading as a herniated disc: illustrative case.

backgroundSpinal dural arteriovenous fistula (SDAVF) is a rare disorder with an unknown etiology. Often, the clinical presentation and imaging findings are misleading, causing this condition to be mistaken for other entities, such as demyelinating or degenerative spinal lesions. OBSERVATIONS: The authors report a challenging case of SDAVF in which the patient's symptoms were initially thought to be attributable to a herniated disc based on his imaging studies at another institution. He sought the authors for a second opinion, which yielded a confirmed diagnosis of SDAVF. Due to his rapidly progressive neurological manifestations, he underwent a surgical division of the fistula using intraoperative video angiography via indocyanine green injections. His symptoms progressively improved over a 3-month period. He regained full sphincter control by 4 months, which gave him a better recovery than seen in other patients with SDAVFs, who do not generally fully regain sphincter control. LESSONS: SDAVF is a critical spinal vascular pathology that should not be overlooked in the differential diagnosis of any patient presenting with signs of progressive myelopathy. Despite its associated vague initial clinical symptoms, SDAVF typically, but not always, demonstrates a characteristic imaging appearance on magnetic resonance (MR) imaging studies; therefore, MR angiography is still required for definitive diagnosis. Surgical treatment for SDAVF is almost always definitive and curative.