wave front lasik

A collection of empirical anecdotes relating to provocative eye issues.

Archive for July, 2007

UV Blocking Contact Lenses

UV Radiation With the summer in full swing and people flocking to the beach, boats and outdoor activities we must turn our attention to sun protection for our eyes. Conventional eye wear for the outdoors has always been good quality sunglasses. These of course come in many forms and at differing costs depending on quality and style.

Over 3 million people per year are getting fit with all types of contact lenses and the obvious question that must be asked is do they or can they protect the eyes like sunglasses. This is not a new concept and has been studied since the 1970s. An avid surfer in California designed sunglass contact lenses for the great outdoors men, but caused substantial visual discomfort when worn in less then very sunny conditions. In addition, the lenses had decreased oxygen transmission due to the pigment in the lenses. These lenses never took off as the real deal.

Some years later when disposable contact lenses became available there were several that were advertised as UV blocking lenses. Unfortunately, none of them ever gave the sun protection that was required. The lenses were also uncomfortable and never became popular.
Over the years many other lenses have come out claiming to give UV protection and some have been quite good, although none of them ever replaced sunglasses.

Recent studies in Ireland have shown that the newest UV blocking contact lenses do give a lot of protection and are the only vision aids that fully protect the cornea from UV light. This is because they cover the cornea and prevent light from coming from the sides at angles the eye glasses can’t defend against. However, the contact lenses do not protect the sclera or white part of the eye since THEY do not cover that part of the eye. In short, neither can fully protect the entire eye from the sun.

The Journal of Investigative Ophthalmology and Visual Science stated that only the contact lenses gave perfect coverage and protection to the eye, but they did not study the affects on the sclera. The bottom line is that both UV Blocking contact lenses and sunglasses do protect the eye from the damaging rays of the sun, but neither is perfect. The best solution is to wear sunglasses over the contact lenses. In cases where the patient is not a contact lenses wearer, we suggest a pair of sunglasses that has some degree of wrap around to best block out the light coming form obtuse angles.

The best way to protect the eyes from the sun will also depend on that activity being performed. Water sports are not good for glasses, but a contact lens may fall out. People should chose the best eye wear and protection for them based on what their needs are.

Beach Safety and Your Eyes

Beach Sitting on the beach today made me remember the 12 years that I spent as an ocean lifeguard. Perhaps the best years of my life, although as all good things must come to an end so did my lifeguard days. I remember watching the pretty girls in skimpy bikinis coming out of the water wandering around aimlessly looking for their beach blankets. Being the gentleman that I am, and a lieutenant in charge of 25 guards, I felt that I had a responsibility to show these young ladies to their space on the beach. While it was a good way to meet them, I often wondered why they could not find their own way around. After giving up the idea that perhaps they wanted a lifeguard to ask them out, I came to the conclusion that they could not see where they were going.

This concept did not occur to me until I became an eye doctor many years later. While it hurt my ego, I realized that back in those days not as many people wore contact lenses and thus had trouble getting around the beach when coming out of the water with out their eye glasses. Today things are much better since there are so many types of contact lenses including daily disposables.

While these developments have made it easier to see one’s way around the beach, it also creates new issues that must be addressed. First, the occurrence of Acanthomeoba, an ameoboid organism in the water has increased the occurrences of infections that can be vision threatening. When wearing contacts in the water these little buggers can get into the lens and cause a nasty infection. Since it often is misdiagnosed the possibility of a bad problem and loss of sight is a real possibility. The way to prevent it is to always dispose of the lens when you get off the beach. That eliminates any chance of secondary infection. Second, when there is wind as there was today on the beach, sand can get into the eye or under the lens. Since sand is nothing more then ground up quarts this can cause severe corneal abrasions and damage the lens. The best way to prevent this is to always wear sunglasses on the beach.

Next is corneal irritation from the salt water. NEVER open your eyes under the water when in the ocean. The salt content and many impurities will cause substantial corneal swelling and pain. The best way to prevent this silly occurrence is DON’T!! Fourth is sun damage. Reflections off the ocean and beach will polarize the light and increase the amount of damaging light getting into the eyes. WEAR good sunglasses like Maui Jims all the time and you will be safe.

Drinking alcohol on the beach will dry your eyes out and make the contact lenses tight and painful. It should go with out saying that drinking in the hot sun and then swimming in the ocean is moronic, but having spent 12 years pulling people out of the ocean in all states of intoxication, I take nothing for granted.

Last but not least, NEVER wash your hands off in the ocean before playing with your contact lenses. BAD IDEA!!! On that last note I am going back to the beach for an evening dip and walk. You see you can take the eye doctor OFF the beach, but never the beach out of the eye doctor.