Characterization of anterior corneal high-order wavefront aberrations and correlations with astigmatism in Chinese elderly subjects.

This study aimed to investigate the distribution of total high-order aberrations (HOAs) Z 3 ±1 , Z 4 0 , and Z 3 ±3 of anterior cornea and their correlations to astigmatism. In addition, the relationship between different axes of astigmatism and Z 3 −1 or Z 3 1 was analyzed. The HOAs in the central 6-mm zone of the cornea were measured with an iTrace wavefront analyzer in 556 cataractous eyes at the Tianjin Eye Hospital in China. Simulated keratoscope readings (Sim k ) were also measured with the analyzer. The corneal total HOAs Z 3 ±1 , Z 4 0 and Z 3 ±3 exhibited a non-normal distribution. Significant correlations were found between the topographic-simulated keratometric power (ΔSim k ) with the axis at 180° ± 5° and absolute value of Z 3 −1 ( P = 0.008), the ΔSim k with the axis at 90° ± 5° and absolute value of Z 3 1 ( P < 0.001), and the ΔSim k and total HOAs ( P < 0.001), Z 3 ±1 ( P < 0.001), and Z 3 ±3 ( P < 0.001). No significant correlation was found between ΔSim k and Z 4 0 ( P = 0.404). In conclusion, corneal astigmatism with the axis near the horizontal position was mainly associated with the value of Z 3 −1 . Corneal astigmatism with the axis near the vertical position was mainly related to the value of Z 3 1 . HOAs except Z 4 0 are correlated with astigmatism. [ABSTRACT FROM AUTHOR]