THE PATHOLOGICAL, SURGICAL, AND MR SPECTRUM OF RATHKE CLEFT CYSTS

BACKGROUND Rathke cleft cysts (RCC) uncommonly attain large enough size to cause symptoms or warrant neurosurgical intervention, leading to difficulty in recognizing their diverse presentations. METHODS We retrospectively reviewed the clinical, intraoperative, pathologic, and magnetic resonance (MR) imaging findings of 16 cases seen at our institution since 1987. RESULTS The most unusual clinical presentation was pituitary apoplexy, although CSF-like, cholesterol containing, or hemorraghic cyst contents most often led to intraoperative misinterpretation. Microscopic features of squamous metaplasia, lymphocytic infiltrates, tubuloracemose glands, or coexistent adenomas demonstrated the pathologic variations in these intrasellar and suprasellar cysts. The MR findings of an anteriorly displaced pituitary stalk, the presence of a posterior ledge, and T-2 hypointensity were distinctive, when present. CONCLUSIONS Rathke cleft cysts have varied clinical presentations and sometimes confusing intraoperative and pathologic appearances. We document a new pathognomonic MR finding in these cysts of a posterior ledge sign. Our surgical approach is to open and drain cyst contents, treat the residual cyst lining with instillation of absolute alcohol, and close the floor of the sella with a bone strut.