Effect of even and odd-order aberrations on the accommodation response

AIM： To investigate the potential effect that odd and even-order monochromatic aberrations may have on the accommodation response of the human eye. METHODS： Eight healthy subjects with astigmatism below 1 D, best corrected visual acuity 20/20 or better and normal findings in an ophthalmic examination were enrolled. An adaptive optics system was used in order to measure the accommodation response of the subjects＇ eyes under different conditions： with the natural aber- rations being present, and with the odd and even-order aberrations being corrected. Three measurements of accommodation response were monocularly acquired at accommodation demands ranging from 0 to 4 D （0.5 D step）. RESULTS： The accommodative lag was greater for the accommodate demands of 1.5, 3, 3.5 and 4 D for the condition in which the even-order aberrations were corrected, in comparison to that obtained for the natural aberrations and corrected odd-order aberrations for the same accommodation demands. No statistically significant differences were found between the accommodation responses under the three conditions. CONCLUSION： The odd and even-order aberrations are not helping the visual system to accommodate, because their partial correction do not affect the accommodation performance.