Commentary on visual hallucinations and Charles Bonnet syndrome.

The authors comment on two case reports of visual hallucinations due to non-psychiatric disorders: retinal detachment in a patient with schizophrenia, and Charles Bonnet syndrome. The physiology of visual misperception is reviewed, based on abnormalities along various points from the eye to the optic tracts to the occipital cortex. The approach to patients with visual hallucinations should include not only an evaluation for psychiatric disorders, but also an appreciation of possible non-psychiatric causes that may have major ramifications for care and potentially for preservation of sight.