Dear Sir,

1-Does the tracker feature have an effect on the procedure precision?

I Have read something about
Different lasik equipment in the following link:
http://www.insightlasik.com/evaluating/excimer.html

http://www.allaboutvision.com/visionsurgery/lasik_laser_2.htm

http://www.ladarvision.com/ladarvision/compare_lasers.asp

2-my prescription is (R: -5.25, 0.75, 175 & L: -4, 0.75, 5) and I
noticed the Dr prescribed a higher degree to enter it in the Computer of the EC-5000. Is there any justification for that (e.g. he used for L eye -4.25, 1.25, 5).

Does the laser beam type affect the smoothness of the treated Ablation area?

Does the smoothness affect the healing duration of the corneal flap?

Which laser beam will give better result in that regard, namely: scanning slit or flying spot.

Does the Laser Beam Type affect the side effects such as ghosting, halos or night vision? which beam is the best to minimize these side effects?

I have not done the procedure yet but, I am trying to choose between Three Drs.:

One is using Nidek EC-5000 (with Scanning Slit Laser Beam) and I have a good background about his experience in the LASIK procedure.

The second Dr is using Technolas 217(Flying Spot) and, I also have good background on his experience in the LASIK procedure.

The third Dr is using MEL 70, but I do not have much information him.

I really need an advise to make my selection.

The first two Drs are excellent in their field, therefore, my selection will really be based on the type of laser used.

Please advise me, if possible. Your help and prompt response is
greatly appreciated.

1-Does the tracker feature have an effect
>on the procedure precision?
DEBATEABLE - DEPENDS ON THE PATIENT - but usually not.

>2-my prescription is (R: -5.25, 0.75, 175
>& L: -4, 0.75, 5) and
>I noticed the Dr prescribed a
>higher degree to enter it in
>the Computer of the EC-5000. Is
>there any justification for that (e.g.
>he used for L eye -4.25,
>1.25, 5).

THE DOCTOR WILL ADJUST WHAT HE ENTERS INTO THE LASER BASED ON A VARIETY OF FACTORS, INCLUDING THE HUMIDITY AND TEMPERATURE.

>Does the laser beam type affect the
>smoothness of the treated Ablation area?

MOST LASERS PROVIDE VERY SMOOTH ABLATIONS. I DO NOT THINK THAT THERE ARE ANY COMPARATIVE STUDIES THAT PROVE THAT ONE LASER HAS BETTER RESULTS THAN ANOTHER LASER. ONE SHOULD CHOOSE BASED ON THE SURGEON, NOT THE LASER (MY OPINION, AND THE OPINION OF MANY OTHER SURGEONS)
>

>Does the smoothness affect the healing duration
>of the corneal flap?

THEY ARE ALL SMOOTH.
>Which laser beam will give better result
>in that regard, namely: scanning slit
>or flying spot.

AGAIN - THERE IS NO STUDY THAT SHOWS THAT ONE LASER TYPE HAS BETTER RESULTS THAN ANOTHER LASER TYPE. PLEASE BE CAREFUL, AS OFTEN SURGEONS WILL PROVIDE A STUDY THAT SHOWS THEIR LASER IS BETTER. BUT OFTEN THERE ARE OTHER STUDIES WITH THE OPPOSITE RESULTS.

>Does the Laser Beam Type affect the
>side effects such as ghosting, halos
>or night vision? which beam
>is the best to minimize these
>side effects?

I AM NOT AWARE OF ANY LASER PROVING THAT THEY HAVE A LOWER SIDE EFFECT PROFILE

Best of luck

Bill Trattler, MD
Miami, FL

Dr Trattler,
Thank you so much for your answer. in your reply you stated that "MOST LASERS PROVIDE VERY SMOOTH ABLATIONS. I DO NOT THINK THAT THERE ARE ANY COMPARATIVE STUDIES THAT PROVE THAT ONE LASER HAS BETTER RESULTS THAN ANOTHER LASER. ONE SHOULD CHOOSE BASED ON THE SURGEON, NOT THE LASER (MY OPINION, AND THE OPINION OF MANY OTHER SURGEONS)"

Surgeon selection is my priority. However I read about surface smoothness comparison in the following link,
http://www.ladarvision.com/pros/library/pdf/REF125.pdf

Do you have any comments on that.
Thanks

The study is many years old, and the lasers have probably all had multiple upgrades in their ablation profile. For Example - the VISX is currently an S3, and will go to S4 in 2003. In the study you provided - the S2 was analyzed. The VISX S3 has a significantly smmoother ablation than in its S2 version.
Of course - the real question is quality of vision and clinical results. Again the problem has been that there have been no good comparative studies, and in general the results are very similar between lasers. So my personal recommendation is to pick your surgeon based on surgical ability, not on what laser will be used.

Best of luck

Bill Trattler, MD
Miami, FL

Again, thanks Dr Bill Trattler for your response, I just forgot to mention that my pupil size is 6 to 7 in dim light. The Dr who was checking used a devise like police radar for speed detection. My cornea thickness is 580, and steepness is 41.

Once again my prescription is (R: -5.25, 0.75, 175 & L: -4, 0.75, 5)

Is there any preference for Techolas over Nidek or the opposite. As I read before, Technolas removes more cornea tissues than Nidek. Would that have an effect in the future? Both surgeons have v.good reputation in Lasik operation.

There is no study that shows that one laser is better than the other. As well, there is no way that I could know whether using the Technolas would nbe "too much" - that is something that you would need to discuss with your doctor.
I wish I had more answers. Perhaps you should see a third doctor to get another opinion.

Best of luck.

Bill Trattler MD
Miami, FL