Decorative Contact Lens Primer

Posted on October 11, 2011 · Posted in Contact Lenses, Eye Health

Halloween is almost upon us again and with it comes the influx of confusion about decorative/cosmetic contact lenses.

Decorative contact lenses that change your eyes into balls of fire, or 4-leaf clovers, or hypnotic swirls are not inherently bad for you.  In fact, many of these lenses are made of the same materials that standard, clear contacts are.  The problem lies in the fact that these lenses are often not properly evaluated on the eye to ensure proper fit, health, and safety.

Contact lenses have multiple parameters that make up your “prescription”.  Most people are aware of the “power” portion of their prescription.  That’s the number your eye doctor prescribes to offset your nearsightedness, farsightedness, and/or astigmatism and allow you to see clearly.  But look closer and you’ll see two other parameters named “base curve” and “diameter”.  Base curve refers to the shape of the lens and diameter refers to overall size.  These two numbers work together with the power and even the material the contact lens is made of to determine how a given lens “fits” a particular eye.

In the fitting of a contact lens, your eye doctor evaluates how the lens sits on the surface of the eye and moves with blinking.  Why?  Because an improperly fit contact lens is bad news.  A lens that is too loose will lead to excessive movement, discomfort, unstable vision, and possibly ejection from the eye.  A lens that is too tight deprives the front of the eye of oxygen, impairs eye defense mechanisms, and promotes infection. Neither of these are good for you.

With that in mind, does it make any sense that a person can arbitrarily purchase a decorative/cosmetic contact lens without that lens material and parameters being evaluated for proper fit?

As eye doctors, we have two main responsibilities when we see you:

  1. Make sure you can see clearly and comfortably.
  2. Make sure you don’t go blind.

Allowing the application of a medical device to the eye without prior evaluation of that device is not doing a very good job of following #2.  Medical journals, and even the internet, are littered with stories of blindness caused by improperly fit contact lenses.

Again, it’s not that colored or decorative lenses are bad for you.  It’s that any type of contact lens applied to the eye without the OK of your eye doctor is asking for trouble.