Rapid change in visual fields associated with suprasellar lymphocytic hypophysitis.

A young woman presented in the third trimester of pregnancy with a rapid onset of bitemporal hemianopia and reduced visual acuity caused by an unusual steroid responsive suprasellar tumor. A computerized tomography scan revealed a 2-cm suprasellar mass which was thought to be a tuberculum sellae meningioma. Surgery was delayed because of pregnancy. A short course of high-dose steroids was given to promote fetal lung maturity. This produced an unexpected and dramatic resolution of the field loss. As the steroid dose was reduced, the visual fields deteriorated, necessitating a craniotomy. The histology revealed lymphocytic hypophysitis, a rare but distinct clinicopathological entity affecting the anterior pituitary lobe. The significance of the suprasellar site and a possible role for the use of steroids in the preoperative management of this condition is discussed.