The presenting visual symptoms of optic chiasmal disease

Recognising optic chiasmal disease early is important in order to avoid irreversible visual loss and the potential risk of mortality for patients. Yet, there is frequently a delay in the initial diagnosis. Whilst the signs of optic chiasmal disease, particularly the perimetric findings, are well documented in the recent literature, the symptoms have been less well reported. Whilst some patients with optic chiasmal disease will be asymptomatic, many will complain of visual symptoms including symptomatic field defects, problems with central vision, difficulty with near tasks, binocular visual disturbances, colour vision disturbances, photophobia, phosphenes, glare, and rarely, oscillopsia and visual hallucinations. Others may have headache or the severe and sudden visual symptoms associated with pituitary apoplexy. The visual symptoms may be vague or non-specific, even when there are significant bitemporal visual field defects. We aim in this review to describe the presenting visual symptoms of optic chiasmal disease, and to illustrate these with selected qualitative descriptions from the literature. Our hope is that this will aid clinicians in eliciting a careful history of the sometimes subtle symptoms that may be present.