Completely extradural intraspinal arteriovenous malformation in the lumbar spine: A case report

Abstract

Introduction. Spinal vascular malformations can be classified in arteriovenous malformations, cavernomas, and capillary telangiectasias. Arteriovenous malformations are the most common spinal vascular anomaly and may be located intra- and/or perimedullary. According to their nidus type and hemodynamic flow patterns, they can be differentiated into fistulous, glomerular and juvenile categories. In our case, a hyperintense extradural mass was misinterpreted as a neurinoma. The histological analysis revealed typical signs of an arteriovenous malformation. Case presentation. A 57-year-old Caucasian woman presented with back pain and hypesthesia in digiti two to four of her left foot. Magnetic resonance imaging showed a long-segment intraspinal extradural soft-tissue mass in the left L4 - S1 paravertebral region with homogeneous enhancement of contrast medium. Due to another similar lesion in the lower ankle and additional cutaneous manifestations, the suspected diagnosis was a systemic disease with neurinomas (e.g. Recklinghausen's disease). To clear up the origin and type of this lesion exploratory surgery with a hemilaminectomy of L5 was performed. This showed abnormally arterialized, dilated, and tortuous vessels. After complete resection, the intra-operative impression of an arteriovenous malformation was confirmed by a neuropathologist. Conclusions: Completely extradural intraspinal arteriovenous malformations in the lumbar spine are extremely rare. In magnetic resonance imaging they are often misinterpreted as a tumor. Arteriovenous malformations can cause compression and venous congestion, or mask symptoms like a spinal disk herniation.In cases presenting with these symptoms and magnetic resonance imaging findings, an extradural intraspinal arteriovenous malformation should be considered as a possible diagnosis. Pre-operative angiography or magnetic resonance imaging angiography can be used to verify the diagnosis. © 2014 Suntharalingam et al.; licensee BioMed Central Ltd.