Data: Femtosecond laser outperforms microkeratome at multiple levels

March 15, 2010

Refractive surgeons currently using a mechanical microkeratome should consider turning their LASIK procedures into all-laser surgery by using a femtosecond laser for flap creation, according to one expert.

Key Points

San Diego-Refractive surgeons currently using a mechanical microkeratome should consider turning their LASIK procedures into all-laser surgery by using a femtosecond laser (IntraLase, Abbott Medical Optics) for flap creation, according to Capt. (retired) Steven C. Schallhorn, MD.

"Based on its versatility and better safety, control, predictability, and visual outcomes, the femtosecond laser should be our instrument of choice for creating the LASIK flap," said Dr. Schallhorn, global medical director of the Optical Express Group, San Diego. "Of course, the femtosecond laser procedure also is more expensive.

His latter statement was based on an analysis of patient preferences from a large cohort of patients undergoing surgery at the center. In a series of 81,300 consecutive eyes of 41,800 patients, 70% of patients chose the femtosecond laser when given a choice of technology for flap creation, despite the fact that the all-laser surgery carried an additional fee of $1,200.

Data from this same patient population provided further evidence that the femtosecond laser procedure offers benefits for greater safety and better visual outcomes compared with LASIK performed using a mechanical microkeratome for flap creation. Although there were few intraoperative flap complications in either group, the rate was lower among patients having the femtosecond laser flap compared with the mechanical microkeratome group (seven eyes, 0.01%, versus eight eyes, 0.03%, respectively).

Furthermore, all of the intraoperative complications associated with mechanical microkeratomes were "showstoppers for completing the procedure," Dr. Schallhorn said.

"The intraoperative complications that occurred with the mechanical microkeratome included lost suction during the pass and buttonholes, whereas with the femtosecond laser the most common problems encountered included suction loss and vertical gas breakthrough. In many of those situations, the cutting could be restarted immediately," he said. "In only two of seven eyes with an intraoperative complication during femtosecond laser flap creation was it necessary to abort the surgery."

Based on data from about 75% of the initially treated eyes seen 1 month after surgery, postoperative complications also were more common after surgery with a mechanical microkeratome. Compared with the femtosecond laser group, the mechanical microkeratome group had a significantly higher rate of flap displacements (0.05% versus 0.004%, respectively), and a two-fold higher rate of primary epithelial ingrowth (0.02% versus 0.01%).