[Case of spinal thoracic-lumbar dural arteriovenous fistula with polyneuropathy type sensory impairment]

A 57-year-old man had progressive paresthesias ascending from both legs together with paraparesis. Distal paresthesias of the upper extremities developed earlier than segmental sensory impairments. At transfer to our hospital, a neurological examination detected bilateral lower limb weakness predominant in the distal part; severe glove and stocking paresthesias in addition to superficial sensory impairment below the Th8 level; and micturition problems. T2-weighted thoracolumbar MRI showed a hyperintense spinal cord lesion between Th5 and L1. At the L4 level, a spinal arteriogram showed enlarged and tortuous vessels extending from the lumbar artery which drains to the spinal vein. These findings led to the diagnosis of spinal dural arteriovenous fistula. Anatomical substrates for this sensory impairment may be produced by development from the side to forward parts of lesions in the outer circumference of the anterior funiculi, resulting in the dominating sensory impairment in the distal parts of the upper extremities. Physicians need to be aware of patients who have polyneuropathy-like sensory impairment without segmental sensory signs, and must consider the possibility of spinal dural arteriovenous fistula.