Peering Into the World of Artificial Eyes
AS THE kite lifted into the air, it bobbed up and down like a small boat in the water. Suddenly, a gust of wind caught the kite! But rather than fling it across the sky, the gust forced it straight down—driving a wire on it right into the owner’s eye. Triumph had turned into tragedy, and an eight-year-old boy was left blind in one eye.
A 20-year-old woman sat fighting fear and panic as she listened to her doctor quietly explain that one of her eyes was diseased, triggered by trauma, and that both eyes would go blind if the diseased one was not removed immediately.
A young girl was blind in one eye. She grew up shy and reserved. She was very much aware that her eyes didn’t match each other like the eyes of most everyone else, and she was painfully aware that the other children knew it too.
When a “Window” Gets Shut
Eyes have been called our windows to the world. Shutting even one in blindness is a traumatic experience. But for many, it means actually losing the eye as well. In the United States alone hundreds of thousands of people wear an ocular prosthesis—an artificial eye.
Each of the above-mentioned individuals has an artificial eye. The first two each eventually lost one eye. The third individual, although still having both eyes, now wears a very thin prosthesis called a scleral shell. This type of prosthesis is specially made for cosmetic and therapeutic reasons and is worn over blind eyes as a protective cover.
Artificial eyes—for most of us they are a mystery. Have you ever wondered what one looks like, or how it stays in and moves? Is seeing with one eye the same as seeing with two? For answers, let’s peer into this seldom-discussed world of artificial eyes, beginning with when an eye is lost.
An Eyeball for an Eyeball
When an eye is removed, the volume, or space, it took up needs to be filled. So a small device called an implant is designed to do this. Today, the standard type of implant used is a round, solid plastic sphere. Once inserted into the empty socket, it is covered over with socket tissue. Thus the implant acts as a pseudo eyeball, filling the void left by the removal of the real eye. Later, the artificial eye will be placed over the implant like a contact lens over a sighted eye. And the normal functioning of eye and lid muscles will move the implant/eye.
However, implants are objects foreign to the human body and therefore can possibly be rejected. Suppose the body succeeds—maybe months or even years later—in forcing the implant out? Then what?
An Implant for an Implant
There are several options. You can try having another implant put in or leave the socket empty altogether. Or you can receive an alternative type of surgery known as a dermal fat graft. In the United States, mostly subspecialists in the field of oculoplastic surgery are trained to do this procedure. Awake! asked one of them, Dr. Frank H. Christensen, to explain briefly more about this unusual operation.a
What is a dermal fat graft?
It is a round plug of skin (dermis) and includes the body fat that is directly attached to that skin. It is cup-shaped and about the size of a cork in a wine bottle. However, variations of this surgery use cartilage or bone instead of body fat.
Why is the dermal fat graft used in place of an implant?
If the body is rejecting a foreign material, it seems logical to replace it with a natural one that the body recognizes—its own living tissue. It’s the more physiologic approach.
Can the dermal fat graft be rejected the same as an implant?
Implants tend to be rejected because they are foreign bodies. Normally, the dermal fat graft isn’t rejected.
Why not initially use this procedure instead of the standard one?
Because we want to perform surgery that has been tested for 30 years and that works in the majority of cases. And the standard procedure does have at least an 80-percent history of doing well. Then save alternatives such as the dermal fat graft for the 20 percent that do not.
Whatever procedure is used, about four to six weeks after surgery, the patient is ready for an artificial eye. So let’s go to the eyemaker’s office and watch him make . . .
“Eye-dentical” Twins
Ophthalmologist, optometrist, optician, oculist—these are terms you may be familiar with. But how about ocularist? An ocularist is a person who makes and fits customized ocular prostheses—artificial eyes.
In the United States his training is by apprenticeship, working five years with a master ocularist. But to qualify for certification by the National Examining Board of Ocularists, he must also follow the educational system of the ASO (American Society of Ocularists). This includes recertification every six years. At this writing, of the approximately 200 ocularists practicing in the United States, less than half are Board certified.
ASO education includes mandatory attendance at lectures given by ophthalmologists (those who specialize in the treatment of diseases of the eyes) and ocularists for the purpose of exchanging information on the latest techniques and procedures used by both professions. How does this benefit the patient?
Suppose a surgeon feels that the artificial eye will automatically correct certain cosmetic problems, such as droopy eyelids. However, it may be that this problem should be corrected surgically rather than by the ocularist, who fits the artificial eye later. Consultation between the two professionals could determine this and resolve other problems. The ASO’s goal is that by understanding their roles in relation to each other, closer surgeon/ocularist cooperation can offer the patient a better cosmetic result.
But some who wear an artificial eye have never been to an ocularist. How can that be? Some opticians (makes or sells optical products) and optometrists (tests eyes and prescribes lenses) can fit a person with a “stock” eye—a mass-produced, premade eye shell. They cannot make an eye but have had a limited course in fitting ready-made eyes.
Do you, like most people, think that all artificial eyes are made from glass? At one time that was true. They were all made from a special soft glass produced only in Lauscha/Thüringen, Germany. But during World War II, that glass supply was cut off. As a result, an alternative material for making eyes was developed—a plastic (methyl methacrylate). Acrylic plastic has proved so successful that today less than 1 percent of all patients wear glass eyes.
But you want to know how these “eye-dentical” twins are made. Join us as Mr. Edwin R. Johnston, a Board-certified ocularist, answers a few questions. (See also the box on page 23 for a brief description of how an artificial eye is made.)
What do you notice most about your patients when they first come?
Very often they’re terrified. They think that they have to go through surgery again and that it’s going to be painful. We show them what an artificial eye looks like and let them know they’re not going to get hurt. We try to impress on them that whatever has happened—the accident, the injury, the disease, the tumor—it’s all over with now. We’re going to bring them back to looking natural.
Is the loss of an eye considered a disability?
Losing one eye is a disability, but it’s not a total disability. If the person really wants to, he can still do almost anything he did before.
Why is an artificial eye more easily noticed in some cases than in others?
First of all, it has to do with the reason for the removal of the eye. Was it because of an injury, and how severe was it? It could have to do with who the doctor was. It could be who the eye fitter or the ocularist was.
How do you know what size to make the eye?
In most cases an impression is taken of the eye socket with its implant and then a mold of that is prepared.
Is this similar to how a dentist takes an impression of your gums to make dentures?
Yes. And there are some skillful ways to take an impression so that you achieve more movement of the eye.
Thus with modern advances, the patient leaves the ocularist’s office looking whole again. But he still has challenges to meet before he can function as before. So, then, what is it like seeing the world . . .
From a One-Sighted View?
In a word—flat. But why is that, since one eye can still see? Losing an eye also means losing depth perception—the ability to judge the size of objects and their distance from you. Depth perception is normally achieved by two eyes seeing the same object from two slightly different angles. In this way people see objects in three dimensions. A person with one eye still sees the object but only in two dimensions. Thus, the book A Singular View aptly describes that the one-eyed person sees things as “a rather flattened-out scene, much like an ordinary photograph.”
Three-dimensional vision can be regained, however. Depth perception can be created by slightly moving the seeing eye, the head, or the body position to view an object from two different angles. But this takes time, practice, and patience to learn.
In the case of the little boy mentioned at the outset, he was so young that he adjusted quickly and grew up never really knowing what it was like to have normal depth perception. And years later, learning to drive a car was no real problem for him.
But for the 20-year-old woman, loss of depth perception was a major challenge. For example, she had been driving a car for several years when suddenly she had to relearn this skill, using a whole new set of “rules.”
Although learning to see with one eye can be successfully achieved in due course, how can that adjustment be made a little bit easier?
Laughter Can Be a Lifesaver
Being able to laugh at himself and not take himself too seriously will carry the patient through many an embarrassing moment. This is not said to make the problem a light, laughing matter. No, the patient needs compassion. But pity—from himself or anyone else—can be more disabling psychologically than the loss of the eye.
For example, since he has no depth perception he may have the very frustrating experience of holding a bottle of milk, looking right at the glass, pouring, and missing completely! But the patient can’t spend the rest of his life ‘crying over spilled milk,’ so he learns to laugh at it. And until improvement comes, he can pour with the container touching the rim of the glass.
Another problem develops when someone offers to shake hands with the patient or holds out change from a purchase. The new patient isn’t sure where the item is! This problem can be overcome by the patient holding out his hand first and letting the other person fill it with the item. With money that method may appear greedy, but it is better than grabbing at the money several times, missing entirely, and then finally crushing it and the person’s hand by overreaching!
‘If I Had Only Known Then What I Know Now!’
Have you ever said that about something after you learned it the hard way? For the new one-eyed patient, there are many questions and fears. But who quiets those fears or explains how to relearn doing the everyday things of life? Very often, no one. Many patients learn the hard way.
In the case of the little boy we met earlier, he reacted to his situation one way. He recalls: “Since I was so young at the time, I didn’t really think much about the future. I was only apprehensive about how well I would do.”
By contrast, the 20-year-old woman remembers her fears. “Questions raced through my mind: ‘What will I look like? Can I still drive a car? Will I still be able to be physically active? Will anyone notice that I wear an artificial eye? Will someone want to marry me?’”
In both cases, no one explained to them what to expect or how to cope. Encouragingly, though, the fears and adjustments of one-eyed patients are other areas that ASO has begun dealing with in recent years. Society members not only hear lectures on improving medical and cosmetic procedures but also receive practical information on their role in preparing the patient for the new situation.
When All the “Windows” Are Opened Again
Although wonderful strides have been made in improving life for the one-eyed patient, no one has eliminated blindness. Yet that is exactly what the Bible says will happen in the near future. It records accounts of blind people being healed. (Matthew 15:30, 31; John 9:1-7) Those accounts prove that Jehovah God’s promise to restore sight to all blind eyes is credible. The facts are there to back up his words. (Isaiah 55:10, 11) Referring to that day when the “windows” will open again, Isaiah 35:5 says: “At that time the eyes of the blind ones will be opened.”
“That time” has not come yet, so it takes ‘eyes of faith’ to see it now. But since God cannot lie, that “sight” is not based on blind faith.—Titus 1:2.
[Footnotes]
a Awake! is not promoting any treatment or offering medical advice in this matter. Our aim is simply to report recognized professional approaches.
[Box/Diagram on page 23]
How an Artificial Eye Is Made
(Techniques may vary from one ocularist to another)
(1) An impression of the surface of the implant (or graft) is taken. First, a clear plastic shell like a big contact lens is inserted over the implant. Next, a white, pasty substance called alginate is injected behind the plastic shell, impressing the shape of the implant (A). A stone mold is made of this impression. Then a dark disk the size of the iris is placed on the center of the new eye, indicating the position of the iris. The mold and impression are enclosed in a metal flask and cured (heated under pressure) (B). The eye emerges as a white, concave plastic shell (C). With the patient sitting right there, the painting of the eye begins.
(2) The sclera, or white of the eye, is stained, since a real sclera tends toward blue or yellow. The iris is painted—including little flecks, marks, or any other details—to match the real eye (D).
(3) The “veins” are tiny, red silk threads. These are dropped onto the sclera and are squiggled around until there are about as many veins as in the real eye and the squiggles match (E).
(4) The pupil is a black dot cut from a sheet of polyvinyl chloride with an instrument similar to a paper punch. The size is determined by the patient’s age and by how the real pupil reacts to light. The eye is then cured, polished, and fitted once more.
From impression to finish, the eye takes about eight hours to make. How does the eye stay in the socket? It is inserted, like a contact lens over an eye, and then “burped,” or gently pushed in, to make it airtight. It is very secure when in place; physical activity will not jar it loose. Yet it can be easily and painlessly removed with two fingers.
[Diagram]
(For fully formatted text, see publication)
A
Plastic Shell
Alginate
Implant
B
Metal Flask
Stone Mold
Cutaway view of eye being cured in metal flask
C D E
Front View
Back View
[Diagram on page 21]
(For fully formatted text, see publication.)
Artificial eye positioned over implant
Eye
Flesh
Implant