BENIGN GLIAL CYSTS OF THE PINEAL REGION

A review of the pertinent literature regarding glial cysts of the pine al region is presented. Various pathogenic factors have been advocated such as the physiological involution of the pineal gland, a sequestra tion of the embryonic cavum pineale or the degenerative evolution of g lial inclusions within the pineal gland. The pathological description is classical with three layers : an external fibrous capsule, an inter mediate layer of pineal tissue and an internal glial wall. Imaging of these lesions is typical, namely the thin rim of peripheral contrast e nhancement and the presence of calcifications. These cysts are more fr equent in women in their third decade of life. They are almost always latent and their fortuitous disclosure at NMR examinations is common. Some of them will nevertheless cause intracranial hypertension due to hydrocephalus and hemorrhage. Those symptomatic cysts should be treate d. Surgical excision has been the method of choice and the results are good. More recently a mere stereotactic needle aspiration has been pe rformed with satistactory long-term results.