Subependymoma is a benign lesion, slow-growing neoplasm, representing 0.2 to 0.7 % of intracranial tumors. They are often clinically silent, incidentally discovered at autopsy. These symptoms are related to big volume. They are attached to the septum pellucidum, leading to hydrocephalus by Monro foramen obstruction. Overall mean age at diagnosis is 39 years with more males than females. At CT-scan, subependymoma shows a slightly low attenuation compared to gray matter. There is no or mild enhancement following contrast injection. On MR T1-weighted imaging, subependymoma is isointense and hyperintense on MR T2-weighted imaging. Intramural calcifications and cystic components are noted in 20 to 30 % of patients. Peritumoral oedema is absent. Immunohistochemicals studies show intense positivity for S-100 and GFAP. The treatment is surgical with an excellent prognosis.
Víctor Bretón Solo de Zaldívar