Prosthetic contact lenses are different than either cosmetic contacts or those that are used strictly for vision correction.
When you look at someone, one of the first things you notice is the other person's eyes. What you may not notice is that sometimes, those eyes that peer back are covered with prosthetic contact lenses. These Lenses are not the same as prosthetic eyes. The prosthetic contacts fits right over the eye, just as any type of contact lens
Prosthesis is any artificially-created device that's been created to replace a body part. Most often it's the prosthetic limbs that grab the media attention, but prosthesis can be created for various body parts including heart valves, teeth and even the eyes.
What is the difference with prosthetic eyes ? Prosthetic contact lenses are not the same as prosthetic eyes. When just the lens needs replacement, it means that the eye still is intact. The prosthetic contacts fits right over the eye, just as any type of contact lens would. It requires the same type of maintenance routine as other types of contact lenses and it feels the same, too.
These special effects contact lenses are perfect for people who have suffered an eye injury that has caused the eye to become somehow disfigured. They're also worn by individuals who have lived with an eye defect since birth. Such injuries and defects can leave the eye looking abnormal. For example, sometimes there is one big black circle where normally there would be a dark pupil surrounded by an eye color.
A condition known as albinism might result in one eye being lighter in color than the other. The pupils might for some reason be misshapen or a person may have a deficiency in his or her color vision.
Special effect contact lenses can also be used to realign an eye that has 'crossed'. No surgery is involved and when the lens is put into place, the colored part of the eye appears to be in its 'normal' position in the center of the white area as opposed to the corner.
Prosthetic contact lenses can disguise such inconsistencies making the eyes less awkward to look at for the affected individual. As a result, the self-confidence that a prosthetic contact lens provides to a patient with a discoloured eye due to scar tissue, eye disease or blindness is amazing.
These contact lenses aren't always needed to correct a vision problem, although they can easily be made that way. Oftentimes, they're purely cosmetic in nature.
A unique manufacturing process
Since each reason for needing prosthetic contact lenses is unique, so too is the manufacturing process.
The easiest way to create this type of prosthetic device is to work from close-up pictures that have been taken of both eyes. Digital photographs work best and provide the truest colors making it much easier to match eye color and any unique eye coloring patterns.
The prosthetic contact lenses can be hand painted or tinted to perfectly match the other eye, creating a perfectly symmetrical appearance to the eyes. There are also standard tint lenses available for very dark eye colours with no variations or very limited colour variations within the iris. The pupil is set at a normal daylight size, which is based on information provided from the other eye in average light.
The hand painting or custom tinting process is very detailed. Digital images of the patient's normal eye are sent to the lab where the painting and design of the pupil and iris are completed.
These very skilled professionals will make an exact match for the colours, variations, flecks, spokes and the actual size of the iris. For those patients that have a limbal ring, the darker ring around the iris, this detail can also be included to create the perfect match.
The pupil size in a prosthetic contact lens remains constant, it does not dilate and contact based on the ambient light in the environment.
This is the one visible issue that may allow an observer to see that the eye is damaged or not functioning.
However, this would only be noticeable in dramatic lighting changes such as very bright or very dim lighting.
Maintenance of prosthetic contacts :
Typically prosthetic lenses are used in lieu of an artificial eye implant and may only require changing once a year or even less frequently.
Most are cared for the same way as all daily use contacts and are removed and cleaned each evening and put back in the eye when needed. Since these lenses are not used for vision, rather for creating a matching appearance to the eyes, they may not be worn on a daily basis; this is up to the client.
Caring for these contact lenses is no different from normal contact lens maintenance routines. Because of the hand-crafted nature of these lenses, they generally are not made to be disposable.
That means daily cleaning and disinfecting and weekly enzyme cleansing routines to remove protein build-up are important to both preserving the coloring of the contact lenses as well as preserving the health of the eye.