Purchase this article with an account.
L. M. Johnson, N. J. Coletta; The Effect of Refractive Error on Changes in Peripheral Aberrations With Accommodation. Invest. Ophthalmol. Vis. Sci. 2010;51(13):4299.
Download citation file:
© ARVO (1962-2015); The Authors (2016-present)
Both accommodation and peripheral refraction have been implicated as factors in myopia development, and as such, recent studies have investigated the relationship between peripheral aberrations and accommodation (Lundstrom et al., 2009, Mathur et al., 2009). We examined differences in peripheral aberrations with accommodation in different refractive error groups.
Aberrations were measured with a COAS aberrometer on forty young adult subjects whose mean Spherical Equivalent (SE) refraction ranged from -12 D to +6 D. Subjects fixated a high contrast letter reflected through a beam splitter, which was mounted between the eye and the COAS. The beamsplitter was rotated to alter gaze position. A Badal lens and a translational stage were used to both correct the eye’s refractive error and to control the accommodative stimulus. Measurements were taken in 10o steps out to 50o on the horizontal meridian and out to 40o on the vertical meridian, at 0 D and 4 D accommodative demands. Zernike coefficients up to 7th order were corrected for elliptical pupils in eccentric gaze positions. Changes in coefficients were analyzed for differences between emmetropes (EM, less than -1.0D), low myopes (LM, between -1.0D and -6.0D), and high myopes (HM, greater than -6.0D). Meridian directions are specified for the retinal position.
We found several differences in how the coefficients changed with accommodation for the different refractive groups. Compared to the other groups, HM showed a smaller increase in C(2,0) and C(2,2) with accommodation across the horizontal meridian. These effects were significant temporally from 10 to 50 deg (p<0.015) and nasally from 10-50 deg (p<0.001), respectively. LM and HM showed a larger increase in C(3,1) nasally than EM (p=0.015). On the inferior vertical meridian, LM and HM showed a larger increase in C(3,1) (p<0.001) and a larger decrease in C(5,1) (p<0.001) compared to EM. Near the fovea, inferiorly, LM and HM both showed a larger negative shift in C(4,0) than EM (p=0.022) and a positive shift in C(6,0) (p<0.001) relative to EM.
Peripheral aberrations changed differently with accommodation in myopic and emmetropic eyes. These effects may be associated with differences between the groups in the crystalline lens optics, optical alignment, or the peripheral retinal contour.
This PDF is available to Subscribers Only