Assessment of femtosecond flap complications has clinical value

HONG KONG — Femtosecond laser technology has firmly taken root as an important tool in refractive surgery. However, an assessment of potential complications can hold valuable clinical lessons, according to one surgeon here. Roy S. Chuck, MD, PhD, presented an overview of his personal complication profile from his first 1,000 cases using the IntraLase femtosecond laser (Advanced Medical Optics).

Roy S. Chuck

Dr. Chuck has been using the IntraLase for approximately the past 5 years, and "it now comprises 90% of my refractive surgery practice," he said at the World Ophthalmology Congress.

The first complication Dr. Chuck outlined was an incomplete flap, which he said occurred in four cases of the 1,000-case series. He said these complications were resolved fairly easily by passing the IntraLase again using the same patient interface. If the flap is lifted and adhesion is minimal, he suggested attempting blunt instrument lysis. If there is significant adhesion, he recommended replacing the flap and performing PRK at a later date.

He described having a few cases of decentered or small flaps, yet none were decentered or small enough to abort the procedure. His solution is to make a slightly larger flap of around 9 mm to 9.5 mm because it is easier to accept a slight decentration than to recenter a smaller one, he said.

Dr. Chuck had two cases of slipped flaps, as well as two cases of partially slipped flaps induced by trauma. He said neither of the traumatically induced cases had to be re-treated.

The highest complication rate was with diffuse lamellar keratitis, which occurred in 20 to 30 cases. All but one case was mild, and most cases were associated with power adjustments and upgrading to higher-frequency pulse engines.

The most interesting complication Dr. Chuck described was that of gas bubbles in the anterior chamber. He said he had two cases in the 1,000-case series, but since then has had between eight and 10 more cases.

He said these are of unknown etiology and are not related to flap perforation. He said once it is determined that there is no perforation, the excimer laser procedure may proceed. But surgeons might experience some gas bubble interference with iris registration and pupil tracking.

Dr. Chuck said that because about 20% to 30% of all flaps in the United States are made with IntraLase, "it's a technology that appears is here to stay," so surgeons should be aware of potential complications and how to address them.