Wavefront-guided LASIK improves visual acuity but increases most higher-order aberrations

J Refract Surg. 2009;25(6):524-533.

Wavefront-guided LASIK for myopia significantly improved visual acuity and contrast sensitivity, a study showed.

"Despite an increase in higher-order aberrations, wavefront-guided LASIK yields excellent visual acuity and contrast sensitivity," the study authors said. "Spherical aberration, which increases the most following non-wavefront-guided LASIK, showed no significant change."

The prospective study included 324 eyes of 162 patients who underwent bilateral wavefront-guided LASIK. Patients had a mean age of 37.7 years (range, 20 to 60 years). Mean preoperative spherical manifest refraction was –2.84 D (range, –0.25 D to –6.50 D); mean astigmatism was –0.81 D (range, 0 D to –4 D). Investigators used ETDRS charts to assess best corrected visual acuity and sinusoidal ratings to gauge contrast sensitivity. A Shack-Hartmann wavefront sensor was used to measure higher-order aberrations over a 5-mm pupil.

Study data showed that 136 eyes (84%) had uncorrected visual acuity of 20/20 or better at 6 months postop. Also at 6 months, 131 eyes (80.9%) were corrected to within ±0.5 D of targeted refraction.

Data showed statistically significant improvements in high- and low-contrast BCVA (both P ≤ .001), photopic contrast sensitivity (P < .001) and mesopic contrast sensitivity (P < .001).

All higher-order aberrations, except spherical, increased in magnitude, the authors said.