Ependymal cyst in the lumbar spine associated with cauda equina compression

There are many reports of extradural ependymal cysts in the literature; however, reports of intradural ependymal cysts are very rare and there has been no prior mention of an ependymal cyst originating from the filum terminale. In this report we present the case of a 31-year-old woman with an ependymal cyst that caused cauda equina compression, and discuss the clinical profile of the case in terms of symptoms, diagnostic images, pathohistological findings, and surgical procedures. To our knowledge, this is the first report of an ependymal cyst that caused cauda equina compression. The cyst was successfully treated by excision of the cyst during careful intraoperative monitoring to prevent neurological damage to the conus medullaris and cauda equina.