Further evaluate pituitary lesion with hypermetabolic activity on PET. There is a hypoenhancing lesion in the left pituitary gland that measures up to 10 mm. There is no mass effect upon the optic apparatus or cavernous sinus. There is minimal deviation of the pituitary infundibulum to the right. The cavernous carotid artery flow voids are intact. There are minimal scattered nonspecific punctate foci of T2 hyperintensity in the cerebral white matter. There is no evidence of acute infarction. The ventricles and basal cisterns are normal in size and configuration. There is mucosal thickening within the maxillary sinuses.
A hypoenhancing lesion in the left pituitary gland that measures up to 10 mm likely represents an adenoma, which can display marked hypermetabolism on 18FDG-PET. 