Several studies have examined initial differences in results for mechanical and laser LASIK flaps. This study looks at long term results of these bladed versus bladeless laser flaps in LASIK eye surgery.
I am blogging from the annual meeting of the American Society of Cataract and Refractive Surgery, held this year in San Francisco. Thousands of ophthalmologists are here all over the world for this specialty eye surgery conference that looks at the latest thinking in both cataract surgery and refractive eye surgery, including LASIK and PRK.
I attended a scientific paper presentation yesterday that I found quite interesting that I’d like to share regarding the LASIK flap. The flap in LASIK can be created either by a mechanical microkeratome or a femtosecond microkeratome. Today despite the fact that there has been a recent increase in the number of cases performed using “all-laser” LASIK with the femtosecond laser flap, both nationally and internationally there remains significant debate as to which is the better technique. Several studies, including a study I recently published, have looked for initial differences in results between the two approaches for making a flap. In particular, many of these studies have focused on initial differences in flap thickness predictability, complication and safety rates of mechanical versus laser flaps, and initial visual outcome differences.
The scientific paper I heard yesterday is one of the first to look at truly long term differences in outcomes between a mechanically made LASIK flap and a laser flap. The study had been conducted at the University of Michigan and looked a patients who had previously undergone LASIK with either a mechanical microkeratome flap or a laser flap between 7 and 10 years ago. Patients were asked to come in for vision measurements, optical measurements, and dry eye evaluation.
This excellent study, presented by Jonathan Greene, M.D. of the University of Michigan, found no significant differences in visual outcomes, optical outcomes, or dry eye between patients that had undergone LASIK with a mechanical flap and a laser flap 7 to 10 years earlier. It really didn’t seem to make a difference which flap technique had been used in these two groups. Interestingly, in both groups, the eyes were equally drier than they had been at the time of surgery, but Dr. Greene felt this possibly was due to the fact that these patients simply were 7 to 10 years old and therefore had drier eyes due to their now older ages rather than any effect from their previous LASIK.
This is an important study in my opinion as it adds to our growing body of literature which compares now the long term, as well as initial, differences between mechanical flaps and laser flaps.
See Also
Femtosecond Laser versus Mechanical Microkeratome for LASIK
This study found equal safety outcomes for mechanical microkeratome LASIK flaps and laser LASIK flaps, but better outcomes at three months for laser flaps when used in the LASIK correction of farsightedness (hyperopia).
Mechanical Microkeratome versus Femtosecond Laser
This article concludes that there is a slight advantage to using the mechanical microkeratome over the femtosecond laser for making LASIK flaps.
Femtosecond Laser versus Mechanical Microkeratome for LASIK: A Randomized Controlled Study
This study showed similar results at 6 months between bladeless and mechanical LASIK flaps, although there was more light backscatter in the bladeless (laser) flap group.
Dry Eye Associated with LASIK: Mechanical Microkeratome versus Femtosecond Laser
This study from the Cleveland Clinic shows a lower rate of dry eye in the femtosecond laser group, which is not what was found in the University of Michigan long term study.
Comparison of the IntraLase Femtosecond Laser and Mechanical Keratomes for Laser In Situ Keratomileusis (LASIK)
In this study, flaps made with the Intralase outperformed flaps created with two popular mechanical microkeratomes.
Femtosecond Laser versus Mechanical Microkeratome LASIK for Myopia: Meta-Analysis of Randomized Controlled Trials
According to meta-analysis (review of multiple studies), the bladeless (laser) flap did not have an advantage over the mechanical (bladed) flap in LASIK eye surgery.