Corneal higher order aberrations by Sirius topography and their relation to different refractive errors

Purpose: to compare the root mean square (RMS) of anterior corneal higher-order aberrations (HOAs) in patients with refractive errors. Methods: : This retrospective observational study was conducted at Department of Ophthalmology, Tishreen University Hospital, Latakia, Syria. The eyes were divided into four groups based on refractive error: mild-to-moderate myopia, hypermetropia, myopic astigmatism, and emmetropic eyes as controls. The following anterior corneal HOAs were evaluated using the Scheimpflug-Placido Sirius (CSO, Italy) topographer over 6 mm pupil: Root mean square (RMS) total corneal HOAs, RMS trefoil, RMS coma and RMS spherical aberrations. Results: : RMS values of total HOAs, trefoil and coma showed a statistically significant difference in all four groups (P < 0.05, all). They were lowest in the control group (0.18± 0.09, 011± 0.08 and 0.09± 0.08 μm, respectively) and highest in the myopic astigmatism group (0.31± 0.16, 0.15± 0.12, 0.17± 0.14 μm, respectively). RMS spherical aberration was lowest in the astigmatism group (0.00± 0.16 μm) with a statistically significant difference from that in the control groups (0.05± 0.07 μm, P = 0.049). Conclusion: The mean RMS values of total HOAs, trefoil and coma were highest in the astigmatism group and lowest in the control group. However, spherical aberration was minimal in the astigmatism group.