Does this scan help you narrow your differential?
It should. The presence of macroscopic fat (also visible on the initial CT) inferiorly and to the right of the mass, adjacent to the posterior clinoid process suggests that this mass is a teratoma (craniopharyngiomas do not contain fat (although they can have high T1 signal components)).
MRI scan was obtained with difficulty due to patient motion. Suprasellar mass which displaces the pituitary stalk to the right is noted, which is mostly cystic (4.1cm) with a large avidly enhancing nodule (15mm) and a fatty component on the right, inferiorly. The optic chiasm lies just anterior to this lesion. The lesion displaces the left optic tract inferolaterally. There is prominence of the optic nerve sheath bilaterally without overt papilloedema. The third ventricle has been obliterated and the cerebral peduncles are splayed by this lesion.
Tiny amount of blood layers in the right occipital horn, likely related to the drain insertion. No abnormal diffusion restriction detected.