Abstract
Purpose :
To characterize the difference between corneal infrared reflex (IR) and pupil center (PC) referenced ocular wavefront aberrations for a cohort of compound myopic astigmatic subjects fitted with orthokeratology (OK) and multifocal contact lenses (MCL).
Methods :
Sixteen subjects with refractive error of plano to -5.00D of sphere and -1.25 to -3.00D of astigmatism were included in this cross-over study. All measurements were taken after 10 ± 2 days of daily wear of OK and MF contact lenses in a randomized order, with a 14 ± 2 days washout period in between. Only the right eye data were used in this analysis. Total ocular aberrations were measured with the iTrace aberrometer (Tracey Technologies, Houston, TX) referenced to both IR and PC locations under dilated pupil conditions. All wavefront aberration data were reported through the eighth radial order over a 5.0 mm pupil. Vector lengths denoting the distance between IR and PC locations were calculated. Coefficients of individual Zernike aberration terms in the second to fourth radial orders were compared between IR and PC referenced measurements (IR – PC) using t-tests with Šidák adjustment for multiple comparisons. Higher order root mean square (HORMS) wavefront error and logarithm of the visual Strehl ratio (logVSX) for terms up to the sixth radial order were also calculated.
Results :
The IR location was temporal to the PC location (both p < 0.001, vector lengths were 0.22 ± 0.08 mm for OK and 0.23 ± 0.09 mm for MCL). IR referenced measurements were greater than PC for C3 with MCL (p < 0.001, difference: +0.23 ± 0.14 µm) and C8 with both OK and MCL (p = 0.002 and 0.035, differences: +0.17 ± 0.14 µm and +0.09 ± 0.10 µm, respectively). When viewed in terms of total aberration present or visual image quality, there was no difference between IR and PC referenced measurements for HORMS and logVSX with both OK and MCL (all p > 0.05).
Conclusions :
While moving between the IR and PC reference points for eyes fitted with OK and MCL led to statistically significant differences in specific Zernike terms, no significant difference was detected in optical (HORMS) or visual image quality (logVSX).
This is a 2020 ARVO Annual Meeting abstract.