Ependymal lined paraventricular cerebral cysts; a report of three cases

SUMMARY Three cases are reported, each with a benign ependymal-lined cyst which produced clinical signs and symptoms simulating cerebrovascular disease or cerebral neoplasm. The pathologi-cal features are described and their histogenesis discussed. Intracranial cysts lined by ependyma which are large enough to give rise to symptoms are rare. Virtually all references to ependymal lined cysts in the literature relate to the colloid or para-physeal cyst of the third ventricle. This communication describes three cases in each of which a large cyst with watery content was found in the centrum semi-ovale. In no case could communication with the ventricular system be demonstrated. All presented with severe neuro-logical signs and symptoms. None was diagnosed during life. Two were thought to have a neo-plasm and the third was considered to suffer from cerebrovascular disease. As the pathological de-scription will demonstrate, the cysts were non-neoplastic, probably developmental in origin, and should have been amenable to surgery