MR demonstration of Wegener granulomatosis of the infundibulum, a cause of diabetes insipidus.

We report a case of Wegener granulomatosis causing hyperprolactinemia followed by central diabetes insipidus. The initial T1-weighted MR image showed an isointense heterogeneous sellar mass. After the onset of diabetes insipidus, repeat sagittal and postcontrast T1-weighted images showed marked infundibular thickening, enlargement of the sellar mass, and enhancement of both the infundibulum and hypothalamus. Follow-up MR after marked clinical response to corticosteroids showed nearly complete resolution of the aforementioned abnormalities.