[Spinal arteriovenous malformation fed by branches of the internal iliac artery (author's transl)]

A 51-year-old male had lumbago and intermittent progressive gait disturbance for 2 years. Finally, he could not walk due to paraparesis. Neurological examination revealed flaccid paraparesis, dysuria, constipation and sensory disturbance below the L-4 dermatome. Myelogram showed serpiginous filling defects from sacral to thoracic region suggesting spinal arteriovenous malformation. Angiogram performed by conventional selective injections into the subclavian, intercostal, and lumbar arteries demonstrated no abnormal lesions but abdominal aortogram carried out at the aortic bifurcation revealed spinal arteriovenous malformation fed by branches of the right internal iliac artery. The angiographic findings may be identified at the single coiled vessel type of Doppamn's or A-V shunt type of Saito's classification. Laminectomies were performed from Th-8 to Th-9 and Th-12 to L-2. Feeder was clipped and the drainers were partially removed. No intramedulllary extension was recognized. After one month postperatively, the patient could walk with support. Postoperative angiographic control performed by selective injections into four iliac arteries disclosed no abnormal vessels. Angiographic examinations of the spinal arteriovenous malformations are usually limited to branches of the subclavian, intercostal and lumbar arteries. But at the cauda equina or conus medullaris, anterior and posterior spinal arteries are sometimes anastomosed with medullary feeders from lateral sacral or other hypogastric arteries. Therefore, it is possible that these branches of iliac arteries may feed spinal arteriovenous malformations as seen also in the cases reported by Picard, Stein and Heindel. This report emphasizes the importance of selective iliac angiogram to demonstrate spinal arteriorvenous malformations when conventional methods fail to show lesions.