blurry

How Trevor Linden Sold Out

This was originally written and posted in December 2010. As with all of the older posts, I've decided to leave this one in its (somewhat naive, but well-intentioned) original condition. The follow up to this was called "How Trevor Linden Sold Out: The Prequel". (Yes, I like movies)


Before I begin, I would like to say that as most kids growing up in Vancouver through the 1990's, I considered Trevor Linden to be an idol. A great hockey player and role model. As an adult, and more specifically as an eye care professional, my opinions have evolved.

As usual, I'll try to present my information as fact and do my best to remain impartial. But, I can't make any promises ;)

Many of you have probably seen our good friend Trevor on TV, or on the many obnoxious billboards around Vancouver, advertising for clearly contacts. Smiling with his spectacles on while promoting glasses and contact lenses for cheaper prices. "Glass, plastic, and two tiny little screws..." says Mr. Linden. Is that so?

Allow me to present the following points in a bulleted format.

  • First, I would like to challenge the notion that glasses are simply glass, plastic, and screws. For those people for whom glasses are a daily necessity, their presence cannot be so cheaply simplified and their importance so easily ignored. Glasses change people's lives. When Johnny Nash sang "I can see clearly now, the rain is gone...", what he was really saying was "I can see clearly now, I have my glasses on". True story. Glasses are a patient's windows into the world. They are a reflection of a person's personality and style. Try to fit that into $38, Trevor.
  • Second, my boy Trev had laser surgery a few years back so he's probably forgotten about the importance of specs. We'll see where he shops once he starts needing reading glasses.
  • Third, quality and service (or lack there of) cannot be overlooked. What happens when the arm falls off your glasses? Or you need to have the frames adjusted? Will you take them to the Linden residence?

Buying Contact Lenses Online:

A contact lens can be considered a medical device. A lens is essentially a prosthesis. A piece of precisely designed silicone and plastic placed on the surface of the eye for a medical purpose.

If poorly fit, over-worn, or misused contacts can cause inflammations, infections, and neovascularization of the eye which can potentially be vision threatening.

Would you consider it prudent for an amputee to go shopping for a prosthesis online without the consultation of his doctor? Or maybe a cardiac patient can look for good deals on heart valves while buying his new glasses? After all, they are both just pieces of plastic, right?

Trevor Linden, it's time to stop making a "spectacle" of yourself.

 

Lil' Wayne and cataracts

"You can't see me baby boy, you got them cataracts" - Lil' Wayne in Best Rapper Alive

Who said rap music is bad for you? I think its educational! Lil' Wayne may not know exactly what a cataract is, but he definitely has the right idea.

A cataract is the clouding of the lens that is inside the eye. As the lens becomes more clouded, vision becomes blurred due to light being blocked or scattered. This is the same lens that we use to focus at near objects. The same lens that stops working around the age of 45 and forces people to start wearing reading glasses (See: presbyopia in the "All Kinds of Blurry" post).

Everyone will develop cataracts at some point in their lives if they live long enough. How much and how fast depends on the individual and the environment. Medical conditions like diabetes can cause cataracts to develop faster. Sunlight is the main environmental factor. So, grab those sunglasses!

Congenital cataracts - It is possible to be born with a cataract. I recently saw a 5 year old boy who had a cataract in one eye. Another reason why kids should have regular eye exams.

Traumatic cataracts - Getting hit in the eye can cause a cataract. Wear protective lenses whenever possible!

How do you treat cataracts?

The only treatment is removal. The cloudy lens is removed and new clear plastic lens is inserted in its place. The surgery takes about 10-15 minutes per eye and requires an incision less than half a millimeter in size!

Who knows, maybe next week Kanye West will rap about Macular Degeneration... Stay posted!

 

"I spent a G on these frames, but my vision is priceless" - Lil' Wayne

 

All kinds of blurry

In my very first post I wrote a little about myopia, which is near-sightedness. Here we'll discuss all the other "-opias" and "-isms" that can make your vision blurry. They are generally referred to as "refractive errors".

A quick review of Myopia. It is due the eye being longer than average. So, rather than an image being focused right on the retina, it falls a little short. Of course, this gives us blurry vision for distant objects which can be corrected with "minus" prescription glasses and contacts, or laser surgery. Example of near-sighted prescription is: -3.25.

 

Hyperopia. This is what we call far-sightedness. As you would expect, a hyperopic person would have more trouble with near and less trouble with distance. This is a result of the eye being a little bit shorter, thus images fall behind the retina. This is corrected with "plus" prescriptions. Also can be corrected with laser.

 

Astigmatism. Is not affected by the length of the eye. Astigmatism is a result of the shape of the front of the eye (the cornea). With astigmatism, the cornea is not perfectly round, it is a little steeper in one direction than the other. The common analogy is a basketball compared to a football. So, light cannot be focused to one point on the retina. It is split by the different curves of the cornea. To correct this, the prescription needs two powers (one for each curve of the cornea). An example of this would be -1.50 -0.75 x180. The "-0.75" is the astigmatism part of the prescription and "x180" shows that this prescription needs to be placed at 180 degrees. Astigmatism can be corrected with glasses, contacts, and laser.

 

Presbyopia. The first three refractive errors are mostly hereditary. The last one, however, is purely age-related and happens to everyone. As we age, the accomodative system (system inside our eyes that helps us focus at near) slowly stops working. Eventually, as we make it through our 30s into our 40s, we notice that things up close are not as clear as they used to be. Often, patients will say that they need to hold reading material further away. And eventually no matter how far away you hold it, its just not clear enough! Correction usually involves reading glasses, bifocals, or multi-focal contact lenses. Laser surgery is not a very useful option because it does nothing to improve the accomodative system.

What does 20/20 Mean?

 

This week's topic is something I get asked almost everyday. Unfortunately, the answer is never as simple as it may seem. I will do my best to explain it here.

 

Simple definition: 20/20 is the size of letter that the average person should be able to see when fully corrected (assuming that there are no visual opacities or retinal problems). It is what we aim to achieve when correcting patients with contact lenses, glasses, and laser surgery.

 

More specifically: A 20/20 letter is exactly 8.726mm in height at a distance of 20 feet.

 

FAQ:

Q: Does 20/20 mean "perfect vision"?

A: No, this is a common misconception. There really isn't such a thing as perfect vision. The sharpest estimated human visual acuity is about 20/8. Which, with a little math, equates to a minuscule 3.49mm letter at 20 feet!

 

Q: How is the size of the letter determined?

A: The letter size for 20/20 is based on the average spacing of the light-sensing cells in the retina, thus the average eye's ability to discern spaces between letters

 

Q: Why 20 feet?

A: That is the approximate distance at which the internal focusing system of the eye (used for near vision) is relaxed thus allowing your eyes to effectively see into the distance.

 

Q: What if I can't see any of the letters without my glasses? Does that mean I'm Legally Blind?

A: Vision without correction does not really provide any significant information about your eyes (other than the fact that correction may be needed).

The definition of Legal Blindness in Canada and USA is 20/200 in the better eye with correction. Thats 10 times the size of a 20/20 letter.

 

Q: Do I need to see 20/20 to drive?

A: No. This may come as a surprise. But, the legal requirement for driving is 20/40 in one eye. That's double the size of a 20/20.