I have poor eyesight. It began degrading when I was about 10 but has pretty much stabilised. I require a lens at about -5.5 diopters which is medium myopia. Aside from meaning that I need glasses or contact lenses it also means that I have a higher chance of pigment pigment dispersion syndrome or pigmentary glaucoma. Anyway, I wear contact lenses and have been using extended wear (the type you wear continuously without removal for a month - or much longer if you like to live dangerously).
As a guy 'with glasses' I'm often encountered with the question of whether I'd consider laser surgery. Lasik is pretty popular at the moment and seems to do a good job. I thought I'd write about why I do not consider this a good option for most people.
First Lasik surgery is commonly only performed on a small central portion of the cornea which means that during the day, when your iris is contracted it works fine. However, in low light and at night when the iris is open the bad gets in with the good and vision can be degraded. There is probably a way around this issue, such as lasing a larger area, so in the future this might not be a problem. There are, however, other reasons.
If your myopia gets worse getting a second stint of laser correction is not normally an option because they remove some of the cornea everytime and it isn't usually thick enough for more than one correction. This is a good reason not to bother.
Presbyopia - i.e. that thing that happens as you get old. As I age I'll not be able to see things that are close as well as I can now. Currently without any correction I can see stuff that is as close as 5 cm away, and with my lenses in as close as 11 cm away. [side note - it is pretty cool being able to focus on objects that are only 5cm from the eye, good for seeing fine detail and usually only babies have near vision this good. This ability is a feature of myopia. The 11 cm with the lenses in is fairly normal for a guy my age]. As I age this will get worse, to the point when 1m might be the closest distance for objects I can focus on. This is unavoidable. However, this distance of 1m is with normal eyes (aka with my lenses in or glasses on) without them this will be nowhere near as bad. Myopics are less susceptible to the effects of presbyopia. - So, by permanently correcting myopia using laser surgery, one condemns oneself to poor close up vision in later stages of life.
Also, I don't see the point or the unnecessary expense. With new contact lens technology it is like you don't have bad eyes at all. I don't even notice my normal continuous wear lenses anymore... except in dusty environments or when I go swimming or do sports or lose one. This is the rub. The problem that is avoided with laser surgery. However, there is a way around this too.
Yesterday I picked up a new set of contact lenses as part of a research study I volunteered for. These lenses are hard and work by temporarily deforming the surface of the cornea (Orthokeratology lenses). They work as normal contact lenses but you can wear them overnight and then not need any correction whatsoever during the day. Thus all the problems: going swimming or displacing a lens when doing sport or getting grit in your eye, are removed. So the benefit of being able to see without correction.
Interesting point. You can not work for the police (for example) if you had moderate or worse myopia and have had laser surgery to correct. But you can work for the police if you have moderate or worse myopia but can see unassisted as a result of the use of orthokeratological lenses.
I'll update how these cool new lenses go.
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