Contact lens wearers run the risk of eye infection when their lenses are inserted without being properly cleaned and disinfected before use. However, proper cleansing depends on:
• the type of lens,
• allergies the wearer might have, and
• if the eye is prone to protein deposits from the lenses.
Types and Use of Lenses / Cleaning and Disinfecting
There are two types of contract lenses: hard lenses and soft lenses. Hard RGP (rigid gas-permeable) lenses are constructed from plastic, fluoropolymer, or silicone that allows oxygen to permeate through the lens to the cornea. They retain their shape and are most often recommended for patients with astigmatism and those that require bifocals / multifocal corrections. They are also preferable for those who have allergies or whose eyes tend to form protein deposits from over-wearing the lenses.
However, most contact lens wearers prefer soft flexible lenses. Disposable type lenses are expensive but convenient. They are recommended for those with allergies or whose lenses tend to form protein deposits. They are removed and replaced nightly, weekly, or monthly.
Daily-wear lenses may be purchased are the least expensive. They must be removed and cleaned nightly. Extended-wear lenses may be left in overnight but must be removed for thorough cleaning and disinfection weekly. Due to the greater risk of corneal infection, they are not as frequently recommended.
Soft lenses correct near- and farsightedness, and astigmatism. Cleaning and disinfecting soft lenses is specific to the lens material. They come in a variety of colors that change the eye-color and / or appearance of the eye. Color lenses are available by prescription and should be fitted by an eye care professional since over-the-counter color and circle lenses can cause eye injury, infection, or vision loss.
Lens / Eye Infection
Eye infections can be caused by improperly fitted lenses that scratch the eye or causes blood vessels to grow into the cornea. The most common lens-related eye infection is keratitis, an infection of the cornea caused by herpes, fungus, bacteria, or microbes. Keratitis can lead to corneal scarring and the eventual need for a cornea transplant. Vision loss or blindness can occur if the infection is left untreated.
Symptoms of eye infections caused by poor contact lens care include:
• blurry vision,
• eye redness,
• tearing or eye discharge, or
• light sensitivity.
Proper Lens Care
Eye care professionals provide proper lens care guidelines. Eye infection risk varies with the type of contact lens (i.e.: RGP, extended-wear, disposable, etc.). Regardless of the type of lens, proper lens care is essential to good eye health. The risk of eye infection from unclean lenses can be reduced by:
• washing hands with soap and water, rinsing and drying them before removing and replacing lenses,
• observing the “rub and rinse” step in the cleaning process,
• minimizing water contact during contact lens wearing,
• do not rinse or store lenses in tap or sterile water,
• do not use saline solution / rewetting drops to disinfect lenses,
• do not re-use or “top off” the lens solution, and
• airing-out and periodically replacing the lens case.