MR of the pituitary gland postsurgery: serial MR studies following transsphenoidal resection.

PURPOSE To determine the MR appearance of the pituitary gland in the early and late postoperative periods in order to distinguish operative complications more effectively and to establish a postoperative baseline. METHODS Ten patients were prospectively studied with MR following transsphenoidal resection of a pituitary tumor. Early postoperative studies were obtained at 2 to 8 days following surgery, late studies at 4 to 9 months in all patients and also at 12 to 16 months in five. Major observations were height of the pituitary mass and appearance of the surgical packing. RESULTS Within 8 days following surgery, the height of the pituitary mass was unchanged in two cases, increased in three, and only minimally decreased in five. All decreased in height (average 54%) by 4 to 9 months. Gelfoam packing completely (five) or nearly completely (three) resorbed leaving a normal-size, although deformed, pituitary gland. Fat-packed resection defects persisted (two). CONCLUSIONS In the early postoperative period, the appearance of the pituitary gland is similar in size to its preoperative appearance. Subsequent involution with packing resorption yields a smaller, deformed pituitary gland.