A rare dural arteriovenous fistula of the greater sphenoid wing mimicking demyelinating disease of the central nervous system: a case report

Dural arteriovenous fistulas involving the brainstem and spinal cord are rare and are frequently misdiagnosed as inflammatory diseases. Sporadic reports have described fistulas located at the craniocervical junction, while those located in the anterior or middle cranial fossa are extremely rare and diagnostically challenging. Comprehensive multimodal imaging is essential for establishing an accurate diagnosis. A 56-year-old man was admitted with neck pain and progressive quadriparesis. Cranial nerve examination revealed hoarseness, dysphagia, a weakened pharyngeal reflex, and decreased muscle strength in all extremities. MRI demonstrated multiple lesions in the cerebral white matter, brainstem, and spinal cord. The patient was initially suspected of having a demyelinating disease of the central nervous system (CNS); however, steroid therapy led to clinical deterioration. Subsequent detailed imaging, including CTA and DSA, identified a rare dural arteriovenous fistula (DAVF) with the fistulous point located at the greater wing of the sphenoid bone in the middle cranial fossa. Venous drainage occurred via the basal vein of Rosenthal to the brainstem and spinal cord. The patient was ultimately cured following surgical disconnection of the fistula via craniotomy. We report a rare case of DAVF with the fistula located at the greater wing of the sphenoid bone in the middle cranial fossa, draining to the brainstem and spinal cord via the basal vein of Rosenthal, and initially misdiagnosed as a demyelinating disease of the CNS. DAVFs with perimedullary drainage are frequently mistaken for inflammatory myelopathies. When evaluating longitudinally extensive spinal cord lesions, vascular etiologies must be carefully excluded before initiating immunotherapy. This case underscores that the administration of steroids in the setting of an undiagnosed DAVF may precipitate rapid neurological deterioration and cause irreversible damage.