If you wear contact lenses or are contemplating the idea, there’s a lot to know these days. There are many lens types and materials with new technology debuting everyday. There are also many cleaning and care systems to go with these lenses. How do you know what’s best for you and your situation? The first step would be to listen to your Eye Care Professional (ECP).
Contact lenses have changed since the first models in 1801 and also since the American Optometric Association recognized the increasing requests of the people and allowed the fitting of contact lenses as a normal part of the optometry exam in 1948. As technology progressed over time from flat glass lenses to soft lenses which fit the shape of the eye, soft lenses finally became available for sale in the United States in 1971. At this time, the need for an effective cleaning system became apparent and various methods of care were introduced.
There are a variety of disinfection protocols including thermal, chemical and enzymatic. With the thermal method, the patient basically boils the lipids, proteins and grime off the lens surface. The use of a special heat unit, case and solution are involved in the 40-minute process which, after cool down, allows the lens to go right back in the eye. With the enzymatic process, proteins are removed from the lenses biweekly or weekly with a tablet in a vial. The correct enzymatic type depends on whether the patient uses chemical or heat disinfection and is not as popular as it once was since effective multi-purpose solutions have been introduced.
Multi purpose solutions are the chemical type of cleaning and are the most common forms used today. Hydrogen peroxide systems are also a chemical form of disinfection but have only one use: cleaning. Contact lens solutions are different and perform based on their ingredients. A hydrogen peroxide system is the gold standard of cleaning but is a more intricate system to use. There is a special vial, the peroxide and neutralization involved in this particular system. The peroxide method needs to be handled with care in order to ensure patient safety. Serious chemical burns can result from the misuse of these products. Patients who have sensitive eyes, allergies or the inability to use multi-purpose solutions generally opt for this method. Proper product training is a must for patients to have the safest experience.
Multi-purpose solutions are varied and plentiful for the convenience-minded patient but are also the most misunderstood. These brands should not be confused with saline solution which is only used to flush or rinse eyes and lenses. Saline solutions have no disinfection ingredients and no cleaning capabilities beyond rinsing particles from the lenses. There are different multi-purpose solutions for different lens types. Gas permeable or rigid lenses need the solution specially designed for that lens modality. Out of the 125 million lens wearers worldwide, rigid lens wearers are a small sector of just 4% of the population in the U.S. and even less in other nations. Conventional lenses, which are usually worn and changed yearly, are becoming less requested over time and tend to be reserved for the specialty patient requiring a fix for specific ocular issues.
Other lens types include disposable lenses which are generally two-week to monthly worn lenses, extended wear and daily wear lenses. These lenses can be a specialty lens or typically in the category of hydrogel or, the newest modality, silicone hydrogel. The difference between these last two is the silicone hydrogel’s high oxygen transmissibility. All these lenses require careful cleaning and handling to avoid ocular issues including discomfort, infection or disease states which can result in blindness.
All solutions should be used according to manufacturer instructions. Cleaning and handling not only include basic instructions but common sense as well. There are a lot of misconceptions with lens cleaning and use. Always wash your hands before touching or handling lenses. Use soap and water, and whenever possible, dry them on a lint-free towel. Never shower, swim or hot tub in your lenses. The aerosol mist of your shower is not only comforting but can be hiding the dangerous vision-endangering acanthamoeba bug, a protozoan which dwells in fresh water and soil. This invasive entity can cause great pain and vision loss, sometimes within 48 hours. Never wet your lenses with saliva. There are an overwhelming number of bacteria in your mouth including the 27 new ones the ADA found in 1998. Your eyes are an entry into your body’s system and bacteria can enter easily with improper handling.
Wearers should change their case as often as they change their toothbrush; every two to three months. Your ECP can provide you with a care kit with a case at your exam and a few companies provide a case with your lens solution purchase. Never use tap water in your case and always change your solution daily. Rinse the case with the solution after dumping to clean and let air dry. Never add new solution to old. Most solutions will lose all kill and disinfecting power when “topped off” leaving the lenses at the mercy of any number of pathogens and bacteria.
The best way to keep your lenses clean is to rub them. The FDA rescinded the “no rub” designation in 2010, no longer allowing solution manufacturers to promote that form of cleaning. Research showed patients to have a misunderstanding of how this indication works bringing about a flood of infections, lawsuits and noncompliance. Solution instructions now will begin showing the rub, rinse and soak regimen instead. Always rub your lenses from the inside out to the rim to avoid tearing. A circular motion can stress lens fibers causing a weakening and eventual tearing. And always follow the appropriate wearing schedule for your lens type. Overwearing lenses can cause strain, infections, ulcers and shorten your lens wearing ability over your lifetime.
If contemplating the opportunities of the newer lens technologies, following the basics and common sense can ensure a healthy, enjoyable experience. Always follow your ECP’s care recommendations and the instructions on your solution bottle. The sight you save may be your own