Wednesday, July 25, 2007

Custom Lasix Questions

I have decided to get laser vision correction surgery also known as LASIK. In addition to shopping around for the best deal I quickly realized that not all LASIK is created equal. As I have been researching the procedure, I have become more familiar with the terms that differentiate regular LASIK vs. custom LASIK, wavefront-guided vs. wavefront-optimized, higher order abberations vs. spherical and astigmatism and all-laser intralase vs. microkeratome. The following is a list of questions I emailed my opthomology resident friend Chris. I will post the answers to these questions at a later date.

What I have learned so far is that I definately want custom LASIK. In addition to correcting for the typical spherical abberation and astigmatism, custom LASIK also corrects for other "higher-order" imperfections in the cornea which cause glare, halos, stars, contrast, and night vision problems. Custom LASIK uses the same technology used by modern telescopes to correct for atmospheric distortion. I have problems with night halos and stars and measurements clearly show I have a promenent Coma abberation, so custom LASIX is what I want. Unfortunately, there are other issues to consider.

Intralase vs. microkeratome
I can't really get a good sense on the internet about the pro's and cons of Intralase to make the corneal flap vs. using a microkeratome. The guys who use the ketatome say that using the intrlase technique may have longer healing time and that they have been doing great flaps for years with the microkeratome. The guys who use the Intralase say that the laser is more precise and results in less chance of a winkled cornea (abberation) and the need for a redo later. Intralase people seem to ascribe all future redos to a failure of the microkeratome. I doubt this. Is there a downside to Intralase?

Wavefront guided vs. Wavefront optomized
The LASIK clinic on 15th street use intralase and the Allegretto Wave Excimer Laser. They claim it is wavefront-guided but I see some internet info which say some Allegretto machines are only wavefront-optimized which means it is not truely custom LASIK and the higher-order abberations are corrected using some pre-programed values and not actual precise measurements of your cornea. Do you know if that clinic does true wavefront-guided or just wavefront-optimized? They say its wavefront-guided.

Microkeratomes and Quality of Flap
I didn't appreciate it at the time but it sounds like making the flap is a big deal. Is it a big deal? I am wondering what kind of microkeratome Dr. Bogorad uses. Is there anything special about it? Is is a Bouch & Lomb or AMADEUS II or Zytopic XP? Does it really matter? Does Dr. Bogorad make good flaps? Would he be doing the flap or a resident. If you were helping, would you be doing the flap. Do you think I should have you or another resident do the flap? Are flaps really that difficult to do? I am willing to pay full price if the flap is that critical.

Thickness of Flap
Are thick flaps better than thin flaps. Someone was bragging about their Amadeus II making thin flaps but then I read that thin flaps are more likely to develop a wrinkle. My corneal thickness is over 500 microns which is twice the cutoff of 250. So, Dr. Bogorad or whoever should not be constrained when making a flap.

Size of Flap
Also, the Intralase poeple seem to make a big deal about the size of the flap. The laser supposedly makes a nice big even flap so that a night when your pupil dilates you have less chance of the corneal scar intering into the visual field causing night halos or stars. However, Dr. Bogorad's people assure me that they make big flaps.

LASIK on dilated or nondilated eye.
I wasn't sure if Dr. Bogorad does LASIK on a nondilated or dilated eye. It seems to me that I remember the optho tech saying they do it on a dilated eye. Does this determine how big of a corneal flap you can make? The reason I ask is that I had 2 eye exams yesterday; one not dilated and one dilated. Well, my presciption seemed to be somewhat different dilated than nondilated. My nondilated exam presciption (spherical and astigmatism correction) turned out to be similar to my past presciption. And when they were corrected I could see 20/20 and nearly 20/15. But after my eye was dilated I could see 20/20 but not as well as before and I think the correction numbers where also different. So, I guess I am asking what numbers will they put in the machine. I suppose that if they dilate my eye they should use the dilated numbers and if they dont dilate my eyes during LASIK that they should use the nondilated numbers? What I am really asking is, which is better, not dilating the eye and using the interlaze or dilating the eye and using the microkeratome? Why do you bother to dilate the eye at all. Do you need to dilate the eye to cut a big flap?

2 comments:

DKL said...

Great article. Just had my eyes done on July 20th with an intralase-cut flap and a wavefront-guided laser. Results: Absolutely amazing! My vision at night is better than it's ever been -- higher contrast and more clear.

My eyes feel a bit dry in the morning, but nothing compared to how dry they felt waking up in contacts. There's still a slight haze around bright lights at night, but it's getting less and less every day.

Karina Chiodo said...

I also had Lasik surgery a few years ago and I agree: Lasik is usually tailor-made for each patient. There are a lot of technical terms involved, but in layman's terms, Lasik works. A capable ophthalmologist can perform Lasik surgery with minimum risk and with a very high success ratio.