WFG, WFO LASIK: How much HOA?

In young patients who present with low-to-moderate myopia, minimal astigmatism, and excellent optics, there is no doubt that wavefront-guided (WFG) LASIK with femtosecond laser flap creation is the refractive surgery procedure of choice, according to Dr Steven C. Schallhorn.

A database search was performed to find patients who matched a sample patient with the following baseline criteria: male gender, 28 years of age, myopia –3.5 to –4 D, cylinder <1 D, and a minimum follow-up of 1 month; 28 eyes of 20 patients were identified.

"These are phenomenal outcomes from a relevant, real-world population, and the data are consistent with my opinion that WFG LASIK is the best procedure to give the best possible outcome for patients represented by this specific clinical scenario," Dr Schallhorn said. "WFG LASIK gives the best visual quality with the least induction of higher-order aberration (HOA), and the latter is especially important in the situation where patients have very low pre-existing wavefront error. These individuals come in with excellent visual quality and demand it postoperatively."

In 2009, more than 90000 eyes were treated at an Optical Express centre. The 28 eyes identified after applying the search criteria had a mean manifest sphere of –3.77 D, mean manifest cylinder of –0.42 D, mean best-corrected visual acuity (BCVA) of 20/16, and mean low-light pupil diameter of 6.4 mm.

All had flap creation using the same femtosecond laser [IntraLase FS 60, Abbott Medical Optics (AMO)] and WFG treatment with the same excimer laser (VISX CustomVue, AMO) using a 6mm optical zone and 8mm transition zone.

At 1 month, mean ± SD manifest sphere was +0.05 ± 0.23 D, mean ± SD manifest cylinder was –0.12 ± 0.17 D, and mean UCVA was 20/16+1.

"Zero refraction was targeted for both manifest sphere and cylinder in these eyes, and for both endpoints, the achieved was extraordinarily close to the intended using the WFG procedure," Dr Schallhorn said.