Presentation
Loss of vision.
Patient Data
A large extra-axial CSF intensity lesion expanding the suprasellar cistern with a thin wall, no enhancement or nodularity and no diffusion restriction, extending into the third ventricle, the prepontine and interpeduncular cisterns with splaying of the cerebral peduncles.
This mass is causing displacement and splaying of the vascular structures around, displacing the optic chiasm superiorly.
There is significant mass effect on the brainstem, posterior cranial fossa which appears crowded, the aquedcut of sylvius with stretching of the corpus callosum.
Changes of obstructive hydrocephalus and transependymal edema are also seen.
The pituitary gland and stalk are well identified.
Case Discussion
These changes are most consistent with a suprasellar arachnoid cyst.
Third ventriculostomy is arranged.