Abstract A 51 year old man presented with a two year history of gradually deteriorating vision in his left eye, accompanied by 34 kg weight gain, easy bruising, and hypertension which was relatively resistant to conventional treatment. The patient denied any history of headaches. On examination, his general appearance was as shown (fig 1). On ocular examination his visual acuity was 6/6 in the right and 6/12 in the left eye. A left relative afferent pupillary defect was present and fundoscopically there was left optic nerve atrophy. Numerous investigations were performed, including Humphrey's field analysis (fig 2), and a cerebral magnetic resonance imaging (MRI) scan (fig 3). Eye positions on left lateral gaze were as shown (fig 4).