Ependymoma (IMAGE) St. Jude Children's Research Hospital Caption Ependymomas are brain tumors that arise from cells near the ventricular system of the brain through which the cerebrospinal fluid circulates. They represent approximately six percent of brain tumors in children. Most patients are diagnosed before the age of five years. Microscopic hallmarks of the ependymoma are the rosetted arrangement of cells around a tiny clear canal and pink collars of tissue around blood vessels. Credit Dr. David Ellison, St. Jude Children's Research Hospital Usage Restrictions None License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.