RESUMO
About one tenth of all CNS neoplasms involves the brain. Due to their location in the ventricles they often present similar nonspecific clinical manifestation. Localization and differential diagnosis are dependent on radiological investigation. For the identification of specific CT characteristics of the intraventricular tumors and the differental diagnosis, we retrospectively analyzed 22 pathologically proved cases seen on CT. Important differential features included age and sex of the patient, the location within the ventricle, and the morpholgic appearance of the mass and density on CT before and after intravenous administration of contrast material. Meningiomas (4 cases) and a germinoma showed increased density on the precontrast CT scans, and demonstrated dense uniform enhancement of the postenhanced scan. Choroid plexus papillomas (3 cases) showed dense uniform contrast enhancement. Intraventricular neurocytomas (3 cases) demonstrated characteristic attachment to the septum pellucidum, confinement of the lateral and third ventricle, and calcification within the mass Colloid cysts (2 cases) showed characteristic location of anterosuperior aspect of the third ventricle. In conclusion, CT findings of intraventricular tumors are usually nonspecific. The location of the mass and the patient's age are the most helpful information in the differential diagnosis.