Question of the week

I've talked with several different laser centers, and it seems all of them have different machines, and each claims that their machine is the best. Why aren't all lasers the same?
For the same reason that all TVs are not the same, or all cars are not the same. All excimer lasers that are used in the United States must be approved by the Food and Drug Administration (FDA), but they are of varying quality. The top quality lasers are the WaveLight Allegretto, Visx Star S4, and Alcon Ladar6000. We have used each of these lasers, but by far the most accurate results are obtained with the WaveLight Allegretto laser. Lower quality lasers (like the Nidek or Summit Apex) do not produce the same level of accuracy of results. These budget lasers cost less money to buy and to maintain and are often used by discount centers.

Everyone seems to be talking about Custom treatment. What does this mean?
Custom technology is a major advance in vision correction. Glasses and contact lenses correct each eye with one prescription for the entire eye in order to correct nearsightedness, farsightedness, and astigmatism. But we know that the eye is not perfectly regular, and that different points on the eye actually focus the light differently. Custom technology allows us to measure and treat different locations on the eye with different prescriptions, which cannot be done with glasses or contact lenses. The result is often vision that is better than can be obtained with glasses or contact lenses.

I had Lasik 6 months ago at another center, and now notice patterns around lights with my nighttime vision. Does this happen to everyone who has Lasik?
These patterns around lights, called glare or halos, are common to some degree in all people - including those who have never had laser vision correction. To demonstrate this for yourself, simply look at a full moon, and you will notice that there is a small glow or fuzziness around the edge of the image. It is an inherent part of vision, and most people simply accept it as normal. Immediately after laser vision correction, the glare is usually more pronounced, and in a different pattern, than the glare experienced before the procedure. Typically, this dramatically decreases over a 3-6 month period. For those people who experience this, it is generally something they notice, but not something that interferes with their lifestyle. Glare/halos are more common in 1) laser vision patients with very large pupils, in particular those whose pupils are larger than the treatment area of the laser; 2) patients with very large degrees of correction; 3) treatments with older laser technology. This effect is greatly diminished with the newer laser technologies, which allow treatment zones that are larger than all but the largest pupils. With the newer lasers, 11% of patients say that their nighttime driving ability is now significantly better than it was with their glasses or contacts, 1% say that it is now significantly worse than it was with their glasses or contacts, and the remaining 88% say that night driving after laser vision correction is about the same as it was with their glasses or contacts. We will carefully evaluate your pupil size in 3 different light levels during our Pre-Lasik evaluation, and will provide you with the treatment that is most likely to result in the best daytime and nighttime vision for you.

Can Lasik correct my reading vision?
Lasik alters the shape of the cornea, which is the clear tissue in the very front of the eye. The need for reading glasses that comes as we get older (known as presbyopia) is a result of the aging of the lens deep inside the eye, behind the colored part of the eye. So Lasik cannot correct presbyopia. However, Lasik can be used to create monovision, just as glasses or contact lenses do, in which one eye is adjusted for distance and one for near. Many people have monovision with their contact lenses and prefer it to the alternative of using reading glasses. We can produce the same effects with Lasik. If you are considering monovision, we highly recommend that you try it first (we do this as part of our routine laser vision consultation).

For more information about monovision, please click here.

I wear rigid contact lenses, and have been told that I will have to wear glasses for a few weeks before I can have Lasik. I hate the feel of my lenses, but I LOVE the vision I get from them. Why is it necessary for me to go without them for so long before surgery?
Contact lenses can alter the shape of your cornea, and cause corneal swelling. Prior to performing the laser treatment, we perform measurements that need to be very exact. So, we must allow adequate time out of contacts to be sure that our measurements of the cornea are as precise as possible. We ask our patients to remain out of their soft contact lenses for 7-10 days before the final measurements. If the soft lenses are toric, then they should take out their contacts two weeks before the final measurements. With gas permeable lenses, the patient needs to discontinue their use for a much longer period of time. We use the safe, conservative rule of thumb: one month of gas permeable lens discontinuation for every decade of gas permeable lens use. (During this time you can wear soft lenses.) So, if you've been using your gas permeable lenses for 20 years, you will need to stay out of them for 2 months. We also recommend coming in for a progress check every 2-4 weeks during this process to check on your corneal condition.
 

To see answers to more questions about laser vision correction,
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