Of Roman chariots and goats in overcoats: the syndrome of Charles Bonnet.

Charles Bonnet syndrome (CBS) is a widely under-recognised disorder typically characterised by complex visual hallucinations in the visually impaired. The lack of consensus over a uniform definition for CBS has much to do with the unresolved pathophysiology of the disorder. A leading hypothesis proposes that complex hallucinations arise from visual association cortical areas following their de-afferentation from the central visual pathway. While treatment aimed at improving the visual deficit can limit the symptoms of CBS, at present there is no reliably effective pharmacotherapy for the disorder. Once correctly recognised, a key management principle is to reassure the patient that CBS is a well-documented clinical entity that is not a harbinger of psychiatric illness.