hasegawa mitsuhiro

A case of a large symptomatic intrasellar arachnoid cyst with suprasellar extension is reported. A 53-year-old man was admitted because of decreased visual acuity. Magnetic resonance imaging showed a large intrasellar cyst extending into the suprasellar cistern, with compression of optic nerves. The intensity of the cyst was identical to that of the surrounding subarachnoid space on both T1-, T2-, and proton density-weighted images. Transsphenoidal surgery was performed, but subsequent refilling of the cyst required additional transcranial surgery. Analysis of the cerebrospinal fluid-like cystic fluid revealed high levels of protein and pituitary hormones. Histological study revealed that the cyst wall was composed of connective tissue and arachnoid cells, which were ultrastructurally characterized by a number of desmosomes. Diagnostic, surgical, and pathological features of intrasellar arachnoid cysts are discussed.