Abstract
Purpose: :
Wavefront analysis to calculate higher order aberrations (HOA) is now a routine practice for customized laser refractive surgery. However, limited data is available from large datasets that describe a population. We seek to further understand the effect of aging and refractive error on HOA in a population of patients evaluated for laser refractive surgery and generate normative data.
Methods: :
A retrospective analysis of 1559 consecutive subjects was conducted in patients who were candidates for laser refractive surgery. Wavefront aberrometry (ZyWave, Bausch and Lomb) was performed on subjects older than 18 years as part of the preoperative evaluation process. For the study, data were collected from one eye of each subject and included race, age, refractive error, and third, fourth, and fifth order Zernicke coefficients. Analytic methods included descriptive statistics and multiple linear regression models to identify the relationship between age, refractive error, and HOA. In addition, cluster analysis considering the effect of age and refractive error was performed to generate additional hypotheses regarding these relationships.
Results: :
The mean age was 43.23 ± 12.06 years. The mean spherocylinder was -2.31 (± 2.99) - 0.73 (± 0.82) Diopters x 79.27 (± 53.32) degrees. The following table contains the mean and standard deviations for the Zernicke coefficients:
Overall, HOA tended to increase with age, with third order Zernicke coefficients more strongly related to age than fourth and fifth order Zernicke coefficients.
Conclusions: :
Normative data were generated from a large dataset describing a population interested in laser refractive surgery. Third through fifth order Zernicke coefficients increased with age but third order coefficients were more strongly correlated. Understanding the relationship between HOA over time may lead to more effective surgical approaches that aim to improve vision.
Keywords: aberrations • aging • refractive error development