LYMPHOCYTIC ADENOHYPOPHYSITIS - CONTRAST-ENHANCED MR-IMAGING IN 5 CASES

PURPOSE: To describe observations of adenohypophysitis on magnetic res onance (MR) images. MATERIALS AND METHODS: Clinical enhanced MR imagin g, surgical, and histologic findings were retrospectively studied in f our female patients and one male patient with adenohypophysitis who pr esented with headaches, pituitary insufficiency, or hyperprolactinemia . Results were compared with MR imaging, surgical, and pathologic find ings in 128 consecutive cases of newly diagnosed pituitary adenomas. R ESULTS: In two of the four female patients, disease onset was not asso ciated with a recent history of pregnancy. Imaging findings included a slightly lobulated, intensely enhancing pituitary mass (n = 5); enhan cement along the infundibulum (n = 4); and adjacent dural enhancement (n = 4). Four patients had extrapituitary involvement. Some of these f indings were noted in patients with pituitary adenomas complicated by infarction, hemorrhage, or necrosis. CONCLUSION: The observed clinical and MR imaging findings are suggestive of adenohypophysitis; the latt er, however, are not specific and may be seen in some complicated case s of pituitary adenoma and other rare forms of pituitary inflammation. Biopsy may be needed to establish the correct diagnosis if a trial of steroid therapy fails.