Wavefront aberration changes caused by a gradient of increasing accommodation stimuli.
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ABSTRACT:
SUBMITTER: Zhou XY
PROVIDER: S-EPMC4289835 | biostudies-other | 2015 Jan
REPOSITORIES: biostudies-other
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Project description:Purpose:The aim of the study was to determine and compare the relationship between change in simulated keratometry (K) and degree of refractive correction in wavefront-guided (WFG) and wavefront-optimized (WFO) myopic laser-assisted in situ keratomileusis (LASIK). Methods:A total of 51 patients were prospectively randomized to WFG LASIK in one eye and WFO LASIK in the contralateral eye at the Byers Eye Institute, Stanford University. Changes in simulated K and refractive error were determined at 1 year post-operatively. Linear regression was employed to calculate the slope of change in simulated K (?K) for change in refractive error (?SE). The mean ratio (?K/?SE) was also calculated. Results:The ratio of ?K to ?SE was larger for WFG LASIK compared to WFO LASIK when comparing the slope (?K/?SE) as determined by linear regression (0.85 vs 0.83, p = 0.04). Upon comparing the mean ratio (?K/?SE), subgroup analysis revealed that ?K/?SE was larger for WFG LASIK for refractive corrections of >3.00 D and >4.00 D (0.89 vs 0.83; p = 0.0323 and 0.88 vs 0.83; p = 0.0466, respectively). Both linear regression and direct comparison of the mean ratio (?K/?SE) for refractive corrections <4.00 D and >4.00 D revealed no difference in ?K/?SE between smaller and larger refractive corrections. Conclusion:WFO LASIK requires a smaller amount of corneal flattening compared to WFG LASIK for a given degree of refractive correction. For both, there was no significant difference in change in corneal curvature for a given degree of refractive error between smaller and larger corrections.
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