A bandage lens, also called a therapeutic lens, is a special soft, very thin, high-water-content contact lens. In 1974 this hydrophilic lens was the first type to be used on an extended-wear basis, but without incorporating a prescription. It has a wide variety of uses before ocular surgery, after ocular surgery, and sometimes instead of surgery. It can also be therapeutic in conditions that do not respond to any other form of treatment.
The lens functions basically as a protective shield and prevents a damaged or ailing cornea from coming into contact with the eyelids and the air. Healing is thereby accelerated and pain is alleviated for as long as the lens is worn, which is on an extended basis (more than twenty-four hours). Read the rest of this entry »
This type of lens has been put to artistic use in the movies by actors creating bizarre special effects, such as the eyes of monsters. Ironically prosthetic lenses can also be of real help to those who need something special in order to appear normal. They can dramatically improve the appearance (and sometimes the vision as well) of eyes that have been disfigured or in some way appear abnormal. This includes those who suffer from albinism or unsightly, deformed eyes whose defect is congenital in origin or due to accidental injury or a result of eye surgery. The ultimate type of prosthetic contact lens is the one that forms the “false eye“—or shell over the entire socket when an eye is enucleated (surgically removed).
Prosthetic contact lenses, which may cover the entire sclera or only the cornea, are predominantly manufactured in rigid form, though soft prosthetic lenses are available. The lenses simulate a normal iris and pupil by incorporating an opaque area that is colored artistically to achieve the final appearance of the eye. The desired image may be placed on any portion of the lens, and may be of any color. It is stable and nontoxic because in one type the image is “painted” on the surface of one lens and then covered with another lens, forming a “sandwich.” Another method employs a special tinting process of a soft lens.
CosmeticContact Lenses
For those who wish to change the color of their eyes, especially actors or models, the cosmetic contact lens is a real boon. Some of these lenses cover only the cornea, are made of rigid PMMA material, and are opaque, except in the transparent central area. This clear zone covers the pupil and may have a prescription incorporated. Obviously the lens has to center perfectly. Fitting is difficult and may require many sessions. Care and handling is similar to the standard hard lens. Soft lenses may also be tinted to provide similar cosmetic results.
Contact lenses that you can wear while you sleep—this earth- shattering concept arouses no less interest and excitement than the Pill did when it was first introduced. This is the glamour lens that everybody wants to know about and have, and is probably the lens of the future. Like the Pill, which forever altered our sexual standards, the extended-wear contact lens promises to usher in a new era and change our attitudes toward visual correction. But the similarity doesn’t end there: Though this lens seems to be the answer to every contact lens wearer’s prayers, it has not yet been perfected. It is definitely not for everyone, and some practitioners are reluctant to prescribe it at all.
Canada, Australia, and Europe enjoyed several types of extended-wear contact lenses several years before we did. However, there is no Food and Drug Administration in those parts of the world, and because of this lack of strict monitoring control and quality, these lenses have posed a health problem, especially as related to corneal complications. Read the rest of this entry »
It’s rare for a soft lens to decenter off the cornea because it clings so well to the surface of the eye. However, it can happen —usually when it is inserted or removed incorrectly. If you suspect a lens is off center, cover the other eye; if the vision is blurred, it means the lens isn’t on the cornea. This is no cause for alarm; the lens cannot get lost behind the eye because of the anatomical barriers. The lens will not harm the eye; theoretically it could remain on the sclera for days without adverse effects. However, a decentered lens does your vision no good. Read the rest of this entry »
Surprisingly, all soft lenses are classified as drugs by the FDA because of their ability to combine chemically with medications placed in the eye. (Hard lenses do not.) The FDA must approve every new lens or lens modification as well as the solutions used in their care. Unlike hard lenses and their solutions, which have been around long enough to have been standardized, soft lenses have no established standards because the FDA insists that insufficient information still exists that would provide reasonable assurance of their safety and effectiveness. Every type of soft lens now on the market has been tested first on laboratory animals (which are “sacrificed” so their eyes can be removed and thoroughly examined), and then on a minimum of four hundred human “guinea pigs” for six months (whose eyes—thank goodness—are examined in situ). Read the rest of this entry »
Occasionally a lens will be displaced from the cornea onto the white of the eye or under the eyelids. This may occur during wear, or during a faulty insertion. You’ll know that the lens is not in place by covering the other eye: if your vision isn’t sharp, then the lens is not on the cornea. Don’t worry that the lens will be lost behind the eye: anatomical barriers (the conjunctiva, which covers the sclera and underside of the eyelids in a continuous sheet) prevent this from happening. Don’t panic when the lens decenters; theoretically, a lens can remain decentered on the sclera for hours or even days, and there’s no harm done. I remember a patient of mine who came in to have her eyes examined. Read the rest of this entry »
Contact Lenses Care .
