A Choroid Plexus Papilloma Arising from an Incidental Pineal Cyst t

administration of gadopentetate dimeglumine revealed a weighted and proton density–weighted images 6). to cG.,thin, smooth rim of enhancement of the cyst wall (Fig 1C). The MR findings were otherwise normal. they are hyperintense relative to CSF (4, Kjos et al (7) have attributed these features Received April 28, 1995; accepted after revision September 20. From the Faculty of Medicine, The University of Manitoba (D.A.S.), and the Department of Radiology, St Boniface General Hospital (G.J.MDavid A. Steven, Gregory J. McGinn, and Blake M. McClar Summary: We report a case of an incidental pineal cyst discov-ered on MR imaging that progressed to a choroid plexus papil-loma. The MR features of pineal cysts, the difficulty of distin-guishing benign cysts from cystic neoplasms, and the implications for surgical management are discussed. Index terms: Choroid plexus, neoplasms; Pineal gland, cyst