correlation between refractive, corneal and lenticular astigmatisms and higher order aberrations in refractive surgery candidates

purpose: to evaluate the correlation between refractive, corneal and lenticular astigmatism and higher order aberrations (hoa) in refractive surgery candidates methods: this cross-sectional descriptive-analytical study consisted of 400 eyes (200 patients) who were referred between 2011 to 2013 to farabi eye hospital for refractive surgery. refraction, topography and aberrometry were performed to determine refractive, corneal and lenticular 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 the mean age of 28.2±6.24 years (range 20-52 years) participated in this study; among whom (250 eyes) 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%) had refractive astigmatism greater than 0.75 d. mean spherical equivalent refractive errors in the myopic group was -3.59±1.95 d (range, -0.54 to -10.22 d) and in the hyperopic group was 2.72±0.97 d (range, 0.67 to 4.23 d) with a mean astigmatism of -1.97±1.3 d and -1.3±1.37 d in each group, respectively. the root mean square (rms) of higher order aberrations was 0.38±0.15 µm in all cases. it was 0.38±0.15 µm in myopic group and 0.39±0.15 µm in hyperopic group which positively correlated with se in both groups (p<0.001). there was a significant statistical correlation between corneal astigmatism and hoa (p= 0.03) and between lenticular astigmatism and hoa (p= 0.02). the correlation between refractive astigmatism and hoa was borderline (p= 0.08). conclusion: there are significant correlations between refractive, corneal and lenticular astigmatisms and higher order aberrations. therefore, to achieve better vision and prevention of halos and glare and night vision problems after surgery, we recommend evaluating all aberrations in refractive surgery candidates especially in patients who have high astigmatism to consider them for customized ablations.