Enlarging pediatric ectopic Rathke's cleft cyst in the prepontine cistern: case report.

Rathke's cleft cyst is a cystic disease that occurs in the sella turcica or, occasionally, in the suprasellar area. An ectopic Rathke's cleft cyst is extremely rare, and its nature is less well understood. The authors report the case of a 14-year-old girl who presented with a growing cystic lesion in the prepontine cistern, immediately behind the dorsum sellae. Preoperative imaging and intraoperative investigation showed part of the cyst wall continuing into the dorsum sellae, to the pituitary gland. The cisternal portion of the cyst wall was totally resected via a right subtemporal approach. Histopathological examination of the cyst wall showed a monolayer of ciliated cells, identical to those of Rathke's cleft cyst. To the best of the authors' knowledge, this represents the first pediatric case of Rathke's cleft cyst occurring in the prepontine cistern.