Thoracic dural arteriovenous fistula

Twenty-five consecutive patients with 16 thoracic dural arteriovenous fistula and 9 lumbosacral dural arteriovenous fistulas (DAVFs) were included (mean age, 63.9 years; 20 men). All patients presented with progressive myelopathy. Preoperative and postoperative neurologic deficits were compared between thoracic and lumbosacral DAVF groups. Using magnetic resonance imaging, the extent of T2 high-intensity areas and signal flow voids were documented. Follow-up after surgical interventions ranged from 6 to 96 months (mean, 38.1 months).

Preoperatively, patients suffering lumbosacral DAVF tended to be more severely disabled compared with thoracic DAVF patients. Lumbosacral DAVF patients exhibited diminished patellar (P = 0.04) and Achilles tendon reflexes (P < 0.01), while most thoracic DAVF patients exhibited hyperreflexia. In magnetic resonance imaging, signal flow voids around the spinal cord were evident in only 4 of 9 lumbosacral DAVF patients (P = 0.012). Rather, a serpentine signal flow void of the filum terminale was a hallmark of lumbosacral DAVFs to distinguish them from thoracic DAVFs. In the lumbosacral DAVF group, postoperative improvements were significantly better in micturition function (P = 0.02).

In lumbosacral DAVF, postoperative micturition function recovery was superior to thoracic DAVF. Intradural lumbar signal flow void is indicative of lumbosacral DAVF. For appropriate management, it is important to recognize these differences between lumbosacral and thoracic DAVF ¹⁾.

A 49-year-old man with a thoracic spinal dural arteriovenous shunt (dAVS) in which rupture of a varix caused intramedullary hemorrhage. In the literature, patients with a thoracic dAVS predominantly present with congestive myelopathy; however, the patient featured in this report presented without increased deep tendon reflexes or muscle weakness, but instead with intermittent stabbing chest pain and paresthesia. Magnetic resonance images and angiograms demonstrated tortuous enlargement and the formation of a varix-like structure of the draining veins, features compatible with those of high-flow angiopathy. Recognition of this phenomenon is important in thoracic dAVS because intramedullary hemorrhage dramatically degrades outcome. A high index of clinical suspicion can prevent a similar case of thoracic dAVS from progressing to intramedullary hemorrhage ²⁾.