Objective: Vascular abnormalities associated with neurofibromatosis Type 1 (NF-1) are well known, but arteriovenous fistulae (AVF) are rare and usually involve vertebral AVF. A case of intercostal AVF associated with NF-1 and manifesting as congestive myelopathy is described.
Clinical presentation: A 62-year-old woman with a medical history of NF-1 experienced gradually worsening gait disturbance. Neurological examination at the time of admission found spastic paraparesis, decrease of sensation in the bilateral lower extremities, and vesicorectal disturbance. Magnetic resonance imaging scans revealed flow void sign and a congestive lesion of the thoracolumbar spinal cord, as well as a huge mass in the paravertebral region at T10-T12. Spinal angiography revealed an intercostal AVF with a large paravertebral varix, which drained to the spinal medullary vein and caused dilation of the intradural venous plexus of the spinal cord resulting in congestive myelopathy.
Intervention: Direct surgery was selected for the occlusion of the draining point of the medullary vein, located in the entry of the dura. The patient underwent hemilaminectomy at T10-T12, and the dural entry of the draining vein was occluded. Postoperative angiography revealed no dilated venous plexus of the spinal cord and reduced paravertebral varix. The symptoms were gradually relieved after the surgery.
Conclusion: The present case of a very rare intercostal AVF with an unusual manifestation of congestive myelopathy occurred in a relatively rare association with NF-1. Accurate evaluation of the vascular anomaly allowed selection of the appropriate surgical method.