Male, 18 years old, with hypogonadism. History of pituitary adenoma. A 3 x 3 x 3 mm well-defined linear focus of hypoenhancement is evident within the midline posterior aspect of the pituitary gland. This lesion is mildly T2 hypointense, and is barely cerebral on T1 precontrast images.The pituitary gland itself is otherwise normal in size and morphology. The pituitary stalk enhances normally and deviates very slightly towards the left. The suprasellar cistern is not compromised.
A 3 mm hypoenhancing lesion is evident within the posterior midline pituitary gland. This would be compatible with the stated history of pituitary adenoma, though based solely on its imaging appearance, a Rathke's cleft cyst can also be considered.