A 65 year old man complains of difficulty in driving because of "problems with his vision" which started several months ago, and have progressively worsened since. He also experienced a mild, recurrent, generalized headache during the past few weeks. Close questioning reveals the presence of impotence and decreased libido, which he attributed to aging. His medical, family and drug histories are unremarkable.
S. Prolactin: 22 ng/mL (2 - 18) Cortisol, TSH, FSH, LH, Testosterone, DEHAS: within normal parameters. GH suppression test: within normal parameters.
The MRI of the brain shows a large pituitary mass measuring about 3.5 x 2.5 x 2.5 cm, with superior extension. There is no evidence of cavernous sinus invasion.
The X-Ray appears completely normal.
Perimetry confirms the presence of bitemporal hemianopia.