Paraventricular cerebral cyst in an infant.

The case of a paraventricular cerebral cyst with a partial defect of the corpus callosum is reported. The cyst wall was studied using light and electron microscopy. Electron microscopy revealed that the lining of the cyst consisted by a single layer of epithelial cells. The cells of the cyst wall, which rested on a basement membrane, had microvilli and abnormal cilia, and there were desmosomes between the cells, In accordance with the pathological findings, the cyst was classified as a type transitional between a choroidal epithelial cyst and an ependymal cyst.