Posters

Correlation between refractive, corneal and residual astigmatisms and higher order aberrations in refractive surgery candidates

Poster Details

First Author: M.Mohammadpour IRAN

Co Author(s):    Z. Heidari   H. Mohammad Rabie   M. Jabbarvand   H. Hashemi   M. Khabbazkhoob   E. Jafarzadehpur

Abstract Details

Purpose:

To evaluate the correlation between refractive, corneal and residual astigmatism and higher order aberrations (HOA)c in refractive surgerycandidates

Setting:

Farabi Eye Hospital, Department of Refractive surgery

Methods:

This cross- sectional descriptive-analytical study consisted of 200 patients who were referred between 2011 to 2013 at Farabi Eye Hospital for refractive surgery. Refraction, topography and aberrometry were done to determine refractive, corneal and residual astigmatism and HOA for all of participants and statistical analyses were performed using software SPSS version 20.

Results:

Overall, 400 eyes of 200 subjects with average age of 28.2±6.24 years (range 20-52 y) participated in this study; among which (250eyes) 62.7% of cases were female; According to spherical equivalent 375 eyes (94.2%) were myope and 13 eyes (3.3%) were hyperope and 315 eyes (78.9%) were had refractive astigmatism more than 0.75 D. mean spherical equivalent refractive errors in myopic group was -3.59±1.95 D (range, -0.54 to -10.22D) and in hyperopic group was 2.72±0.97 D(range, 0.67 to 4.23D) and mean astigmatism was 1.97±1.3 D in myopic group and was 1.3±1.37 D in hyperopic group. The mean of higher order aberrations (RMS) was 0.38±0.15 µm in all cases. It was 0.38±0.15 µm in myopic group and 0.39±0.15µm in hyperopic group which was correlated with increase in SE amount in both groups. (p<0.001) There was significant statistical correlation between corneal astigmatism and HOA (p=0.03) and there was also significant correlation between residual astigmatism and HOA (p=0.02). There was marginal correlations between refractive astigmatism and HOA (p=0.08).

Conclusions:

There are significant correlations between refractive, corneal and residual astigmatisms and higher order aberrations. Therefore, to achieve better vision and prevention of halos and glare and night vision problems after surgery, we recommend to evaluate all aberrations in refractive surgery candidates especially in patients who have high astigmatism and consider customized ablations if needed. FINANCIAL INTEREST: NONE