In recent years, the colored contact lenses getting most of the attention have been the plano decorative lenses used for fashion or as a costume, obtained without the all-important involvement of an eye-care professional. These unregulated lenses are a serious public health concern, so much so that a cooperative spirit has emerged within the eye-care industry and it has been pressuring the federal government to act (See sidebar "Where 'Cosmetic' Lenses Currently Stand"). An explosive growth is occurring in this part of the contact lens market. Nearly 25 million patients who currently require vision correction are interested in colored contact lenses (Health Products Research Consumer Survey), as are 13 million non-vision corrected people (year 2000 Gallup poll). A July 2003 article in the Wall Street Journal tells us that global sales of corrective and noncorrective colored lenses climbed about 20 percent in 2002 to $350 million.
As ophthalmologists, we must remember a colored contact lens has far wider applications than just changing a patient's eye color from brown to blue, or allowing him to decorate his eyes in support of his favorite football team during the playoffs. Using a colored contact lens or shell, we can offer comfort and cosmesis to patients with disfigured, misaligned and/or non-seeing eyes. Fitting opaque prosthetic lenses isn't going to generate revenue for most of us, but it does serve a physical and psychological need for our patients who are uncomfortable with the way their eyes look, or have an eye that's been damaged through trauma or disease.
|Remove surface deposits such as those seen in band keratopathy before placing a conjunctival flap and, later, a prosthetic colored contact lens or scleral shell.|
The comprehensive ophthalmologist most often encounters a patient seeking a prosthetic contact lens to hide a disfigured eye, a scarred cornea or a malformed iris. An opaque colored lens might hide a strabismic eye that wasn't successfully treated in childhood. They can also be used to eliminate diplopia and acquired symptoms such as imbalance or photophobia, or disfigurement related to stroke, palsy, myopathy or trauma.
• Masking disfigurement. The most common reason for a disfigured, blind eye is trauma. The demographic groups for ocular trauma are mostly children and young adults who have suffered fireworks injuries, motor vehicle accidents, industrial or work-related injuries and assaults. While we've been able to save the eye in many cases, the patient remains uncomfortable about his appearance and desires a prosthetic lens for a more natural look.
• Hiding strabismus. Persons who are densely amblyopic and self-conscious about a crossed eye can be helped with an opaque colored lens. While hiding the eye is not appropriate treatment for a young child who might still require patching and strabismus surgery, it works for an adult in whom strabismus surgery isn't indicated and who wants his eyes to appear aligned.
Conditions such as albinism, aniridia and cone dystrophy usually leave a patient extremely photophobic. A dark, transparent tint will reduce photophobia for the albino patient, while in cases of aniridia an opaque lens can be used to recreate an iris and a colored lens can help reduce the amount of light admitted into the eye. In this situation, the use of a dark background tinted lens is best with a CIBA opaque ColorBlend pattern as an overlay. Other manufacturers of opaque lenses such as CooperVision and Vistakon have created iris patterns that closely resemble natural eye colors.
|Where 'Cosmetic' Lenses Currently Stand|
|At the present time, decorative plano contact lenses are considered to be "cosmetics" by the U.S. Food and Drug Administration, and as such are subject to the labeling required by the FDA on all "dangerous" cosmetics. The ophthalmic community believes contact lenses must be treated seriously; they are not hairspray or eye makeup. They are medical devices that pose potential serious risks if not fit by an eye-care professional and properly maintained. |
Pressure from physicians, professional groups, voluntary health organizations and American contact lens manufacturers has created an effort in Congress to amend the Food, Drug and Cosmetic Act to read that all contact lenses, regardless of intended use, should be considered medical devices. A version of this bill (HR 2218) passed in the House of Representatives (introduced by Representatives Henry Waxman (D-CA) and John Boozman (R-AR)) in November 2003, but legislation (S1747) sponsored by Senators Mike DeWine (R-Ohio) and Ted Kennedy (D-Mass) is currently held up in the U.S. Senate's Health, Education, Labor and Pensions Committee.
The dangerous consequences of unregulated lenses have touched me personally in my practice in Cleveland. In 2001, I treated a teenage girl whose vision was permanently damaged by lenses she wore solely to change her eye color from brown to green. She bought the lenses at a video store without a prescription. She wore them just once, but developed a Pseudomonas ulceration that caused so much damage that I had to perform a corneal transplant. This patient and others are described in a published series.5 Thankfully, I'm far from alone in my concern about unregulated and unmonitored decorative lenses and appreciate the multidisciplinary efforts of the eye-care community to get the word out on local, state and national levels. Out of the hands of professionals, these lenses pose a public-health risk and should be treated as such.
—Thomas L. Steinemann, MD, Cleveland
An occluder black opaque lens can allow the patient experiencing diplopia to have comfortable single vision. Lenses in "stock" colors should work well, but if a match with the other eye is required, most companies (CooperVision, Adventures in Color) will use a digital photo to match the fellow eye.
If a patient with keratoconus also has a need for cosmesis, you can use tinted lenses as the base in a piggyback system as described by optometrists Janice Jurkus and Jeffery Sonsino.1 They point out that "keratoconic patients wearing a piggyback system may experience less RGP movement if a dot-matrix opaque design is the soft lens base."
A piggyback lens system can also effectively mask corneal scarring. Emory University's Mike Ward and Buddy Russell describe a case2 in which a young woman presented with a full thickness corneal scar with partial aniridia and peripheral anterior synechiae in her left eye. She was fit with a combined rigid/soft piggyback lens system that provided visual acuity of 20/25. A FreshLook ColorBlends (CIBAVision) soft contact lens (median base curve, 14.5 mm diameter, plano, green) was used as the base lens and a rigid Fluorocon (CIBAVision) lens (BC = 8.20 mm, 10 mm diameter, power = +18 D) was placed on top.
When selecting a lens for any of these applications, it's important to recognize your endpoint. If the eye has visual potential, select a lens or lens combination that will first optimize vision, then deal with glare, light sensitivity, etc., and then consider cosmesis. If the eye has no useful vision, the visual consequences of selection of an occluder lens may not be obvious to the patient and the best option may be a painted lens with a good fit.
For the patient with minor disfigurement, a small budget or low motivation to wear a prosthetic lens, the practitioner may choose from a large selection of mass-produced colored lenses with or without refractive power. These may not offer the best color match or the optimal fit, but will satisfy certain patients. Others may be open to more expensive items such as custom-made lenses or scleral shells that are hand-painted and laminated. Standard enhancer tints won't impair vision and the pupillary area can be clear.
To mask serious trauma or a grossly misaligned eye, a hand-painted opaque custom-made lens may be the best choice to completely hide the natural eye and match the "good" one. However, these are expensive to order and to replace, if necessary. With such a wide selection of commercially available colored contact lenses on the market, especially in opaques, a prepackaged lens might just be a good option. This is especially true if the fellow eye is in need of vision correction, because then a matched pair of the lenses could be worn at the same time. For the patient who has visual capacity in the eye in question and needs vision correction, it is possible to take an existing clear corrective lens and send it out for tinting, for example, to help with photophobia or be made darker to mask a disfigurement. Digital photos of the fellow eye are important to guide the manufacturer.
While a discussion of lens types is beyond the scope of this article, I recommend referring to the June 2004 edition of Tyler's Quarterly. It's one of several contact lens industry publications offering a comprehensive listing of tinted daily-wear, extended-wear and opaque contact lenses.
The Ocular Surface
Certainly, you have to first make a traumatized eye or an eye with an unstable ocular surface comfortable before you can fit any contact lens. Treat swollen, blistered ocular surfaces and remove deposits, such as band keratopathy. If dry eye is a problem, try punctal occlusion first as that will impact lens comfort. Aggressively treat lid disorders such as trichiasis, blepharitis, ectropion or entropion.
A conjunctival flap placed over the cornea provides a stable surface for the contact lens or prosthetic shell.3,4 Its purpose is twofold. The first goal is to eliminate ocular surface pain, keeping in mind that blind eyes may have internal or cyclitic pain that cannot be resolved with a conjunctival flap. The flap covers the cornea and prevents painful blisters or deposits from recurring. Some blind eyes, made so by either trauma or disease, develop calcium buildup. We can remove it, but there is a fairly high chance of it re-depositing. In cases of endothelial decompensation, bullous keratopathy too will eventually recur and cause pain. A superficial keratectomy and flap will smooth the surface, remove deposits and provide a stable barrier, eliminating the risk of recurrence under a cosmetic lens or scleral shell.
The second purpose of a conjunctival flap is to prepare the surface of the eye for wearing a prosthetic lens or shell. The surface it provides greatly reduces the chance of irritation of the eye by the lens, leading to vascularization or ulceration, as might happen if the surface were left irregular. The goal is to make sure the lens or the shell has the best fit possible.
Eye Health Considerations
• Oxygen permeability. The lens specifications provided in Tyler's Quarterly reveal that the oxygen permeability of colored contact lenses is, in most cases, somewhat lower than that of corrective lenses and certainly lower than that of the new silicone hydrogels. CIBA's Night & Day lens, a silicone hydrogel, has a Dk of 140. Yet a colored lens by CIBAVision, the FreshLook ColorBlends, lists a Dk of 16.1.
That's nearly a tenfold difference, which is worth noting for some patients with dry eye or ocular surface disease or compromised corneas. Gas exchange has been considered by other authors, including Michael Ward and Buddy Russell 2 who write that "the gas exchange through prosthetic lenses is often limited due to the qualities of necessary materials and manufacturing processes, including placement of opaque backing. This doesn't create a problem for clear corneas with good endothelial function or for heavily scarred and vascularized corneas where oxygen transmission is of limited concern."
• Fit and movement. The fit of a colored contact lens on the eye should be the same as that of a comparable clear corrective lens. Of note, the range of available base curves of colored lenses may not be as large as that of their clear counterparts. A too-tight fit should be avoided at all costs because of potential hypoxia of the cornea, sometimes called tight-lens syndrome. But a lens that is too loose might move around to the extent that the opaque section obscures vision. On a non-seeing eye, however, this would be of little concern. Companies that provide tinting services only, such as Adventures in Color, can work from any lens fit and a digitized photo. Lenses with less than 45 percent water content are preferred.
• Reduced visual field/peripheral vision. Since the clear pupil aperture may be smaller than the pupil size, patients may notice slightly fuzzy vision in the peripheral field. This may be more noticeable under mesopic conditions such as night driving or while at the movies.1 If the patient knows this ahead of time, the symptoms will not be as upsetting when they first appear.
Remember that an occluder lens will do a good job at what it's supposed to do—block vision—such as when one is fit to avoid double vision. Also, take into account that some tints, whether for sports or decoration, may interfere with contrast or change blue and green hues.
As more people enter the colored contact lens market, we should understand the options available in both prosthetic and decorative lenses to best serve our patients. All of these new wearers are going to need proper fitting, education and follow-up. I'm concerned that, as we continue to release contact lens prescriptions as required by law, we will see an increase in damaged eyes. Patients who come to us asking for colored contact lenses, either plano or with power, give us an important opportunity to hammer home the point that unmonitored contact lens wear is a recipe for disaster.
Dr. Steinemann is a specialist in cornea and external disease in the Division of Ophthalmology at the MetroHealth Medical Center in Cleveland. He is also an associate professor of ophthalmology at Case Western Reserve University. Reach him at (216) 778-7144.
1. Jurkus J, Sonsino J. Beyond Blue and Green: The Many Applications of Tinted Contact Lenses. Contact Lens Spectrum. December 2001:24-29.
2. Ward M, Russell B. Prosthetic Lenses: Improving the Way We Look and See. Contact Lens Spectrum. December 2001:30-34.
3. Alino A et al. Conjunctival Flaps. Ophthalmology 1998;105:1120-1123.
4. Steinemann T. Alternative Management for Painful Blind Eyes. Unpublished case report.
5. Steinemann et al. Ocular Complications Associated with the Use of Cosmetic Contact Lenses from Unlicensed Vendors. Eye & Contact Lens 2003;29:4:196-200.