Solitary thoracic intradural extramedullary ependymoma.

Intradural extramedullary ependymomas of the cervical or thoracic spine are extremely rare. We present a 62-year-old woman with progressive thoracic back pain over 9 months. Magnetic resonance imaging rerevealed a thoracic intradural extamedullary tumour which was surgically removed in total. Histologic examination identified the tumour as ependymoma, WHO Grade II. Our radiological and surgical findings are consistent with the hypothesis that these tumours develop from heterotopic glial tissue pinched off from the neural tube during its closure. Copyright 1999 Harcourt Publishers Ltd.