Analysis of high order aberrations in myopic eyes after dark adaptation

Objective To explore the distribution of the high order aberrations in the myopic eyes after dark adaptation and identify the effects of pupillary diameter(PD),refractive power,age and sex on it.Methods In a dark room,using the Wavescan system (Visx,Inc.),189 patients (338 eyes) with myopia were examined across the PD of 5.0 mm,5.5 mm and 6.0mm before LASIK.The root mean square (RMS) values and Zernike coefficients of different orders were analyzed.The patients were divided into different groups based on PD,refractive power,age and sex.Results After dark adaptation,RMS were (0.234±0.093) μm,ranging from 0.05～0.63 μm,and were decreased from third to sixth order aberrations.Among all the aberrations,the most significant ones were coma,trefoil and spherical aberration.High order aberrations were increased with increasing PD and refractive power.The Multiple regression equation between RMSh and PD,SE(spherical equivalent)was RMSh=-0.250+0.098PD+0.007SE.Conclusion After dark adaptation,high order aberrations vary widely among the subjects.The RMS values are decreased from third to sixth order.Among the aberrations,the most significant ones are coma,trefoil,and spherical aberration.High order aberrations are increased with increasing PD and refractive power,especially with the former.The coma and trefoil is increased with increasing age.