An artificial eye is a replacement for a lost natural eye due to injury or illness. Although the replacement can not provide the sight, it fills the cavity of the eye socket and serves as cosmetic enhancement. Prior to the availability of artificial eyes, a person who lost an eye usually wore a patch. An artificial eye can be attached to the muscles in the socket to provide movement of the eyes. Today, most artificial eyes are plastic, with a half-life of about 10 years. Children require a more frequent replacement of the prosthesis because of rapid changes in growth. Up to four or five prostheses may be required from infancy to adulthood.
According to the Society for the Prevention of Blindness, between 10,000 and 12,000 people per year lose an eye. Although 50% or more of these eye losses are caused by an accident (in a survey, more men lost sight of accidents compared to women), there are a number of inherited conditions that can cause eye loss or require a artificial eye Microphthalmia is a birth defect where for some unknown reason the eye does not develop its normal size. These eyes are totally blind, or at best might have some perception of light.
Some people are also born without one or both eyeballs. The so-called anophthalmia, this presents one of the most difficult conditions to properly adjust an artificial eye. Sometimes preparatory work can take a year or more. In some cases, surgical intervention is necessary.
Retinoblastoma is a cancer or congenital (existing at birth) tumor, which is usually inherited. If a person has this condition in one eye, the chances of transmitting it are one in four, or 25%. When the tumors are in both eyes, the chances are 50%. Other congenital conditions that cause eye loss include cataracts and glaucoma. A survey showed that 63% of eye loss due to the disease occurs before age 50.
There are two key steps to replacing a damaged or diseased eye. First, an ophthalmologist or eye surgeon should remove the natural eye. There are two types of operations. The enucleation removes the eyeball by cutting off the muscles, which are connected to the sclera (white of the eyeball). The surgeon then cuts the optic nerve and removes the eye from the socket. An implant is then placed in the cavity to restore lost volume and to give the artificial eye some movement, and the wound closes.
With evisceration, the contents of the eyeball are removed. In this operation, the surgeon makes an incision around the iris and then removes the contents of the eyeball. A ball made of an inert material such as plastic, glass or silicone is then placed inside the eyeball and the wound is closed.
At the end of the surgery, the surgeon will place a conformer (a plastic disc) in the socket. The conformer prevents shrinkage of the receptacle and retains the pockets suitable for the prosthesis. Shapers are made of silicone or hard plastic. After surgery, it takes the patient four to six weeks to heal. Then the artificial eye is manufactured and assembled by a professional eye doctor.