Acute visual loss and pituitary apoplexy after surgery.

Pituitary apoplexy is a dangerous condition, often characterised by acute onset of headache, nausea, visual field loss, and ocular paresis.1 2 The condition is primarily caused by acute swelling of a pre-existing pituitary adenoma. Postmortem surveys have found incidental pituitary adenomas with a prevalence of 5-20%.3 The incidence of symptomatic apoplexy among pituitary tumours is 2-5%.1 2 4 5 These incidences indicate that pituitary apoplexy is more common than is being diagnosed. The underlying tumour is usually found only at the time of the apoplectic episode.6 The term “pituitary apoplexy” also describes acute enlargement of a non-tumorous gland, termed “Sheehan's syndrome,” when seen in the context of obstetric haemorrhage.7 Pituitary apoplexy is initially misdiagnosed in more than three quarters of cases.4 Also, delayed diagnosis and treatment are more likely to result in permanent endocrinopathy and visual impairment.1 2 Death can result from unrecognised pituitary insufficiency or as a complication of decompression surgery. Overall deaths in recent studies varied from 0%2 5 6 to 7%.4 We present two cases of pituitary apoplexy and visual loss after major surgery. In both cases the patient had visual disturbance while recovering. These cases are diagnostically challenging because clinical features such as reduced consciousness and electrolyte abnormalities may be misinterpreted as iatrogenic postoperative complications. ### Case 1 A 48 year old man had elective aortic valve replacement under warfarin anticoagulation. Preoperative sodium was 128 mmol/l. On the day after surgery he complained that the left eye was seeing only “noise” and that the right eye …