Caption

Kayser-Fleischer ring, a brownish ring overlying the outer rim of the iris of the eye. When well developed it is visible with the unaided eye, but faint rings require special ophthalmological observation. It is caused by a deposit of copper granules and is an indication of Wilson's disease, a defect of the copper metabolism. In Wilson's disease excess copper may be deposited in the liver causing jaundice and cirrhosis or in the brain causing mental retardation. If the excess copper is removed from the body by treatment with penicillamine, mental and physical development may proeceed as normal.