- Cauda Equina and Filum Terminale Arteriovenous Fistulas: Anatomic and Radiographic Features
Intradural AVF below the conus medullaris may develop either on the filum terminale or the cauda equina (lumbosacral and coccygeal radicular nerves). Only 3 detailed cauda equina AVFs have been reported in the literature. The authors present the angiographic and MR imaging findings of cauda equina and filum terminale AVF cases, supplemented with literature research to characterize the radiologic features of the 2 entities. On angiography, filum terminale AVFs were invariably supplied by the extension of the anterior spinal artery accompanied by a closely paralleling filum terminale vein. Cauda equina AVFs were fed by either a radicular or a spinal artery or both arteries, often with a characteristic wavy radicular-perimedullary draining vein.