Microsurgical Management of a Spinal Dural Arteriovenous Fistula With Shared Blood Supply to the Artery of Adamkiewicz: 3-Dimensional Operative Video.

Abstract

The presented case is of a 65-yr-old gentleman referred for thoracic myelopathy. He developed bilateral, nondermatomal foot dysesthesia 14 mo prior to presentation, which progressed to numbness below the L3 level. He reported progressive gait instability, bilateral lower extremity weakness, and required a cane for ambulation. He subsequently developed urinary incontinence, while bowel function was spared. The neurological examination upon presentation revealed lower extremity strength was reduced to 4/5 in all major muscle groups bilaterally, while sensation and proprioception were reduced below the L3 level. Patellar and Achilles reflexes were not elicited and clonus was absent. Gait was unsteady and slow. The patient was not able to perform heel, toe and tandem gait. MRI revealed abnormal T2 hyper-intense signal and spinal cord expansion from T6 through the conus medullaris. Angiography revealed a dural arteriovenous fistula (dAVF) originating from the left T9 radicomedullary pedicle, which also supplied the Artery of Adamkiewicz (AoA). The patient underwent T8-10 laminectomies. Prior to disconnection of the fistula, an aneurysm clip was applied to the fistulous point and an indocyanine green video angiogram was completed to show that the fistula no longer opacified, but that the AoA remained patent, which was later confirmed with angiography. As of discharge, the patient's motor exam had improved substantially, though his sensory deficits persisted. This case demonstrates that surgical disconnection is requisite in the treatment of spinal dAVF that have a shared blood supply with the AoA, as embolization risks spinal cord infarction. The patient consented to presentation of this case in a de-identified fashion.