四丘体部choroidal epithelial cystの1例

Choroidal epithelial cyst of the quadrigeminal plate

I．はじめに

　中枢神経系に発生する嚢胞性病変は，その組織発生起源が多様なため多くの種類がある、著者らは，上方注視麻痺にて発症した四丘体部嚢胞例について，その嚢胞壁の検索からchoroidal epithelial cystと考えられた症例を経験した．そこで症例を呈示し，本症の臨床，病理所見を中心に文献的考察を含めて報告する．

A case of choroidal epithelial cyst of the quad-rigeminal plate is reported. A twenty-five-year-old man was admitted to our department because of Parinaud's sign and intermittent headache. CT and MRI showed a cyst in the posterior part of the third ventricle. Left occipital transtentorial approach was carried out and the wall of the cyst was subtotally removed. The cyst contained watery clear fluid. On light microscopy, the cyst wall consisted of a single layer, flat epithelial cells and thick collagenous connective tissue. An electron-microscopic study revealed that the epithelial cells rested on a basement membrane separating them from the underlying collagenous tissue. Microvilli without coating material were presented on the surface of the cells.

With this data in hand, the cyst was considered to originate from the developing choroid plexus.