Thursday, January 14, 2010

What Makes a Disposable Contact Lens Disposable???

I remember when I first started to practice and the only contact lenses we had were hard contact lenses. Then along came soft contact lenses in 1971. The first soft contact lenses were designed to be kept for a long least a year. A few years thereafter the first disposable contact lenses came along. They were initially not very good. Technology improved and today the majority of soft contact lenses that are dispensed are of the disposable variety. Custom soft contact lenses are still being made, but they are often used for specialty purposes. Todays disposable soft contact are excellent. But, what makes a contact lens disposable and why do patients need to consider them?

Technically all contact lenses are actually disposable. The yearly ones are disposable except that you dispose of them yearly. Todays disposable soft contact lenses come in a wide variety of options. There are quarterly, monthly, bi-weekly and daily disposable contacts available. Patients that have eye allergies, very sensitive eyes, dry eyes, etc. often do better changing their contact lenses more frequently. This could mean every day. This is perfect for a daily wear disposable. Daily wear disposable lenses also lend themselves easily to part time wear. Let's say you just want to wear them for sports. O.K. Put on your daily single use contacts and go for it. When the activity is over...just toss them!

Weekly and Bi-weekly disposable soft contact lenses are also very popular. They come in a wide variety of materials. In my office, I prefer the monthly lenses in many cases. This product is easy to maintain and it is always easy to remember when to change the month: toss the old ones and open another pair. The plastics that the lenses are made from is constantly improving. Todays materials are so permeable that, in terms of oxygen transmission, it is almost like a lens is not on the eye.

Because the care of contact lenses has become easier and the product can be purchased in a wide variety of locations including on line sources, patients often forget that soft contact lenses are medical devices. This means that when used properly they are safe and effective, but patients must pay attention to their eyes and seek regular eyecare to make sure that they are not having any negative consequences from their contact lens wear. The safest modality for contact lenses is "daily wear". This means that each day the lens is placed upon the eye and worn for that day. At the end of the day the lens is removed and either discarded (as is the case with single use disposable contacts) or cleaned and disinfected so it can be worn the next day.

The disinfecting systems have gotten better over the years too. Originally, the only system for disinfecting the old style soft contacts was by heating them. Patients had to make their own saline solution using distilled water and salt tablets. We have come a long way since then. Now several companies make multipurpose disinfecting systems that make the care of the lenses much easier. Patients should always thoroughly wash their hands before touching their eyes or working with their contact lenses. The key, when using these multipurpose disinfecting systems, is to make sure that each day the lenses are rubbed between the fingers or in the palm of the hand with fresh disinfecting/cleaning solution. In addition, the old solution should be discarded and fresh solution should be added. The case should be cleaned and air dried every week. The case should be changed every few months to make sure it is clean and functioning properly. There is another system that I like that relies on hydrogen peroxide to disinfect the lenses. This system is especially helpful for patients with sensitive eyes and those that have an abnormal amount of protein in their tear film.

Soft contact lenses can be enjoyed for either full time or part time wear. They offer an excellent way to have an alternate system for vision correction. They are great for sports, social activities and general wear. They come in a wide variety of options including single vision, astigmatism correcting (toric) and even multifocals. They can be used for daily wear or extended wear (leaving them in overnight). The key for patients is to recognize that the lenses are a medical device and need to be evaluated on a regular basis. It is best to see you eye doctor to ensure that you are a good candidate for contact lens wear and for regular maintenance of the contact lenses.

1 comment:

  1. Very informative Dr. Vogel...well done!