Delay in diagnosis of optic nerve and chiasmal compression presenting with unilateral failing vision.

Out of 29 patients who presented with failing vision in one eye due to optic nerve or chiasmal compression, compression was initially diagnosed in only five. The errors in diagnosis and lack of ophthalmological follow-up led to delays of up to many years with serious deterioration in acuity before referral for intracranial investigation. The chief causes of error were lack of charting of the visual fields, too ready acceptance of the diagnosis of the neuritis in the absence of essential features, and the infrequent use of skull radiographs.