Presentation
Galactorrhea.
Patient Data
There is a lobulated lesion measuring 12 x 16 x 22 mm (AP x ML x SI) filling the sella and extending into the anterior aspect of the suprasellar cistern. This is T1 and T2 hyperintense, the T2 signal brighter than adjacent CSF. A rim of slowly enhancing tissue at the left inferolateral margin likely reflects normal enhancing residual pituitary tissue, although this has a marginal planar low T2 signal which may indicate minor calcification or chronic blood product. No definite internal nodule. The lesion displaces the infundibulum anterosuperiorly and distorts the posterior optic nerves, also displacing the chiasm superiorly. No cavernous sinus extension. Cavernous carotid flow voids are maintained. Mucoperiosteal thickening is noted throughout the imaged paranasal sinuses.
Image intensifier in theater demonstrating a transsphenoidal approach for the sellar lesion resection.
Case Discussion
Imaging features of a Rathke's cleft cyst further confirmed on histology:
MICROSCOPIC: The sections show a small fragment of tissue which is covered one surface by a layer of ciliated cuboidal epithelial cells. These show strong immunostaining for cytokeratins CAM5.2 and AE1/AE3. The underlying tissue contains a moderate chronic inflammatory cell infiltrate. No anterior pituitary acini are identified. The features are consistent with the wall and lining of a Rathke's cleft cyst. No evidence of tumor is seen.
DIAGNOSIS: Pituitary cyst wall: Features consistent with wall and lining of Rathke's cleft cyst.