To evaluate the correlation between Refractive, Corneal and Residual astigmatism and higher order aberrations (HOA) in myopic patients.

Three hundred and seventy five eyes of 188 patients aged 28.2±6.24 years were enrolled in this study with a predominance of females (62.7%). Refraction, topography (Orbscan IIz, Bausch & Lomb, Rochester, NY, USA) and aberrometry (Zywave, Bausch &Lomb, Rochester, NY, USA) were performed to determine refractive and corneal astigmatism and HOA for all participants. Ocular residual astigmatism was calculated using vector analysis.

Refractive surgery candidates who were referred to Farabi Eye Hospital were enrolled in this study. The mean spherical equivalent was -3.59±1.95 D. The mean refractive astigmatism was -1.97±1.3 D and the mean HOA was 0.38±0.15 µm in all cases which was correlated with the increase in SE (p<0.05). There was a positive significant correlation between both corneal and refractive astigmatism and HOA (p<0.05) but there was no significant correlation between residual astigmatism and HOA (p=0.122).

The results of the study showed significant correlations between corneal and refractive astigmatisms and HOA. Therefore, we recommend that HOA should be measured in cases with significant preoperative astigmatism prior to refractive surgery.