Abstract
Purpose: :
To investigate the effect of wavefront-guided refractive surgery on higher-order aberrations as measured by the Alcon LADARWave system
Methods: :
Measurements were obtained using the LADARWave device from one hundred eyes (50 patients) who presented for refractive surgery. Two different pre-operative measurements were taken a minimum of one day apart. A single set of measurements was taken post-operatively. The pre- and post-operative measurements were compared with a 2-tailed paired t-test to determine if the data were statistically different.
Results: :
The mean pre-operative and post-operative values for coma 1 were -0.04 +/- 0.25 microns and 0.07 +/- 0.32 microns, respectively. The p-value for the paired t-test comparing this data set was < 0.005. The mean pre-operative and post-operative values for coma 2 were 0.03 +/- 0.14 microns and 0.04 +/- 0.20 microns, respectively. The p-value for the paired t-test comparing this data set was < 0.005. The mean pre-operative and post-operative values for spherical were 0.20 +/- 0.19 microns and 0.27 +/- 0.26 microns, respectively. The p-value for the paired t-test comparing this data set was < 0.005.
Conclusions: :
Wavefront-guided refractive surgery was developed to minimize the induction of higher-order aberrations that occurs with traditional methods of refractive surgery, and to treat pre-existing higher-order aberrations. In our case series, paired t-testing demonstrated a significant difference between pre- and post-operative measurements for all three zernike terms. For each of these tested terms, there was a trend toward a slight increase in post-operative aberration, although the magnitude of the aberrations in all cases was low. Wavefront-guided refractive surgery using the LADARWave device results in excellent clinical outcomes, and the clinical significance of low magnitude higher-order aberrations is unknown. Further investigation is required to evaluate the repeatability of these results as well as their potential impact on objective and subjective parameters of post-operative visual outcomes.
Keywords: refractive surgery: optical quality • refractive surgery: LASIK • refractive surgery: PRK