The first step of the LASIK procedure involves creating a thin corneal flap with either an automated mechanical device called a microkeratome OR a femtosecond laser in the case of All-Laser IntraLASIK. While individual doctors may have their own preference, most objective LASIK surgeons agree that both methods can be very safe and consistently achieve excellent results. Recent clinical studies have shown that Intralase results in less dry eye symptoms, stronger flap adhesion, better safety profile and better vision results than microkeratomes. However, in my assessment of all the relevant data, the statistical differences are relatively small. Microkeratome blade-related flap problems are very rare (about 1 per 2,000 procedures), but are more likely in patients with specific corneal characteristics, such as steep, flat or thin corneas. In these patients, All-Laser IntraLASIK is safer and especially preferable to a microkeratome. Also, for patients that are particularly anxious about the procedure, All-Laser bladeless LASIK may provide additional peace of mind.
Is All-Laser Intralase technology really necessary?
Many times per week I am asked, “Is it MANDATORY to choose the All-Laser Intralase option, or will the less expensive microkeratome option be okay for me?” Ultimately, this is a clinical judgment that is based on multiple factors. While most patients prefer the added safety of bladeless eye surgery, All-Laser LASIK may be more advantageous for some than for others. For patients with thin, flat, or steep corneas, Intralase is clearly safer (and the additional procedure cost is especially advisable). However, based on our real world experience, microkeratome-based LASIK may still a very good option for other patients with normal corneal measurements and no preference for Intralase. I will help guide you to the most appropriate procedure for your specific needs.
I may especially recommend using All-Laser IntraLASIK (or Epi-LASIK/PRK) if you have:
Very steep or very flat corneal shape (normal is between 41-46 D)
Thinner corneas (average is 500-550 microns thick)
Larger amount of nearsightedness
Dry eyes or contact lens intolerance
Anxiety about “the blade” or just want the safest possible technology
If price/cost is not the primary determining factor (additional cost per eye)
Reasons to consider a Microkeratome for flap creation include:
Having very normal corneal measurements
Preferring the longer track record of the microkeratome
Desiring lower cost (if otherwise appropriate)
Is one method of creating a flap preferable depending on whether a Wavefront LASIK treatment or a Standard LASIK is performed?
No. Either method of flap creation is equally compatible with both types of laser reshaping—Standard treatment and Wavefront treatment.
Is All-Laser flap creation proven to be safer than using a microkeratome?
In several large LASIK reviews prior to 2000, it was reported that a significant proportion of complications following LASIK were attributed to faulty creation of the LASIK flap by early prototypes of the microkeratome. This complication rate has dropped significantly with the refinements in newer, better and more sophisticated microkeratomes. Presently, in the hands of experienced surgeons who are using “top-notch” surgical microkeratomes, the rate of microkeratome-related LASIK flap complications is very low (about one complication per 2,000 surgeries).
As of 2010, there is accumulating data showing the advantages of femtosecond laser flap creation. Recent studies presented at the 2009 American Society of Cataract and Refractive Surgery annual meeting demonstrated that there is a lower incidence of various flap problems with the femtosecond laser:
Better flap adhesion strength reduces the potential problem of a shifted flap after LASIK. This finding prompted the US Navy, US Air Force, and NASA to use only All-Laser LASIK for its sailors and aviators.
Lower incidence of epithelial ingrowth (epithelial cells growing under the flap) with Intralaselaser flap creation due to the “right-angled” edge of the flap architecture, similar to a manhole cover.
Lower incidence of dry eye symptoms with thin Intralase flaps compared to microkeratomes.
Are there scenarios in which laser flap creation may be especially preferable to microkeratome technology?
Yes. In certain patients, flap creation using laser technology may have more clear-cut advantages over flap creation using microkeratome technology. These include patients with extreme corneal shapes (thin, flat, or steep corneas), large refractive errors or eyes prone to corneal abrasion. Also, if a patient is very anxious about the procedure, some patients may feel “peace of mind” knowing that there is not a “blade” involved in the process. During the preoperative evaluation, I will advise you if your medical situation warrants a decided preference for a particular technique of flap creation.
Is there additional cost associated with femtosecond laser technology?
Yes. Because of added equipment costs and per procedure fees applied by the laser manufacturer, the cost for All-Laser flap creation is higher than for microkeratome flap creation. In certain cases this additional cost of Intralase is indicated and others it is not really medically necessary.
How should a patient decide one technique versus another?
For the majority of patients, both methods of flap creation can be considered as “safe”, and therefore surgeon and patient preference will be important factors in deciding the LASIK flap creation technique. Some patients may prefer the safety of “All-laser” LASIK techniques whereas others may prefer the lower cost and long track record of microkeratome-based technology.
At the Laser Eye Center, we are very experienced with both types of technology and will discuss which of the various LASIK treatment options may be applicable and best for your treatment during your personal consultation.