Exophytic ependymomas of the spinal cord.

Intramedullary ependymomas of the spinal cord with exophytic components are rare outside the filum or conus region. Two cases of combined intradural intramedullary and extramedullary ependymomas of the spinal cord are presented. At operation, the tumours proved to be primarily intramedullary but had a contiguous exophytic component that extruded either through a defect in the ventral pia to encase the anterior spinal artery in one patient, or through the dorsal root entry zone in the second patient. When removing intramedullary spinal tumours with an exophytic component, separate removal of the intramedullary and extramedullary components is recommended, rather than en bloc resection, to prevent possible injury to the vascular supply of the spinal cord.