Article

CUSTOM SOFT CORNER

CARING FOR COLORED LENSES

It is imperative that practitioners provide patients with specific instructions on how to clean, rinse, and store their customized cosmetic or prosthetic contact lenses. The proper steps to follow vary from one manufacturer to the next. An understanding of why this discrepancy exists can help practitioners educate their patients to increase their chances of being compliant with the care and handling of their colored lenses.

Manufacturing Technique

A cosmetic lens that has been manufactured using a molded-lens technique generally has each pigment molecule fully encased by polymer. This method ensures that the pigments are safely protected from the corneal surface (Figure 1). For this reason, today’s mass-produced, reusable, boxed soft tinted cosmetic lenses can be safely cared for with any solution that is compatible with soft contact lenses.

Figure 1. Using a molded lens creation process, compatible pigment is sandwiched within the polymer to completely encase the pigment molecules, resulting in a smooth front surface.

Alternatively, pigment can be pad-printed to a custom lathe-cut soft contact lens and then cured or baked at a high temperature to securely adhere the pigment to the anterior surface of a lens (Figure 2). Some lenses have computer-generated prints or pigment that is hand-painted onto the lens surface. While these lenses offer the highest level of customization in terms of iris detail and color matching, the pigments are more exposed to the ocular surfaces and to reactions that may occur with different types of contact lens care solutions.

Figure 2. Using a pad-printing and curing creation process, compatible pigment is baked onto the anterior surface in this customized cosmetic contact lens, and its texture can be visualized with the slit lamp.

Release of Pigment

Multipurpose solutions (MPSs) have a variety of different preservatives that are often incompatible with the pigments used or with soaking over time, increasing the chances of pigment leaching from or of pigment molecules dislodging from the lens surface. Each manufacturer has its own unique ink formulations and would know best regarding the chemical compatibilities with the variety of care solution ingredients.

Intensity of Tint

Some manufacturers advise to avoid all hydrogen peroxide-based care solutions—and alternatively recommend a MPS—to maintain a high level of pigment quality. Although preservative free, hydrogen peroxide care systems can fade certain pigments used in the tinting process. Custom cosmetic lenses can be pricey, and a change in the appearance of the lens can impact print quality and color consistency.

Bottom Line: Trust Your Lab

Across the contact lens industry, there is no consensus regarding the care and handling of tinted contact lenses. Most of the customized contact lenses have an annual or bi-annual replacement cycle; to optimize their life cycle and to maintain eye health when worn, a proper daily cleaning regimen is required. Practitioners should contact the individual lab with which they are working for more information on how to proceed. CLS