Fig. 4

Magnetic resonance imaging (MRI) scans at recurrence and after biopsy. a Enhanced sagittal T1 sequence: scans after the recurrence of headache in Sept. 2014 showed an enlarged sella with a slightly sunken bottom. The pituitary was enlarged with a height of 1.15 cm and showed a heterogeneous signal, with a patchy, short T1 signal and an abnormal, long T2 signal. The pituitary stalk was shortened and thickened. b Enhanced coronal T1 sequence: a new lesion was detected after recurrence. There was nodular enhancement with abnormal T1 and T2 signals on the right side of the suprasellar region; the lesion was invading the pituitary stalk, infundibulum, right optic nerve, posterior right basal gyrus rectus of the frontal lobe, anterior perforated substance and extending to the internal carotid artery. c and d Enhanced T2 sequence: cerebral parenchymal edema was detected around the lesion. e Enhanced sagittal T1 sequence: changes were observed in the pituitary after the biopsy and i.v. administration of glucocorticoids. f Enhanced coronal T1 sequence: after the biopsy and i.v. administration of glucocorticoids, the parenchymal edema was significantly reduced