IT HAS generally been felt that ependymomas arising within the brain do not spread or form implantations on distal parts of the cerebrospinal axis. However, a few cases have been reported in which it must be concluded that such spread or implantation did occur. The first such report of such a case is believed to be that of Spiller,1 who later referred to a similar case.2 Thereafter, Cairns and Russell3 reported the case of an ependymoma of the roof of the fourth ventricle with small metastases to the pia mater of the fifth thoracic segment. Tarlov4 described the observation at operation of a pea-sized cervical implantation, and Dyke and Davidoff5 referred to 3 additional cases in which an ependymoma was associated with spinal implants. Two cases were added to this series by Tarlov and Davidoff.6 In a recent study of gliomas producing "meningeal gliomatosis,"
CHUSID JG. EPENDYMOMA IN THIRD AND FOURTH VENTRICLES WITH IMPLANTS IN SPINAL SUBARACHNOID SPACES. Arch NeurPsych. 1948;59(3):408–413. doi:10.1001/archneurpsyc.1948.02300380137013