Visual hallucinations after acute visual loss in a young child.

A four-year-old boy developed complex visual hallucinations consisting of moving figures, animals and other familiar objects one week after becoming totally blind. This followed a six-month period of gradually deteriorating vision and was precipitated by the debulking of a large optic nerve glioma. Although visual hallucinations are well recognised in adults with visual loss, secondary to both ophthalmological and neurological causes, they have not been reported in young children.