Abstract
Purpose :
Compared to a natural lens, existing commercial intra-ocular lenses (IOLs) are characterized by degraded peripheral optical quality due to the presence of optical errors such as peripheral astigmatism (PA) (B. Jaeken et al., IOVS, 2013). The current study reports the PA results from a bench test method compared to clinically measured in pseudo-phakic eyes.
Methods :
Intraocular lenses were measured on an optical bench using a wide-angle physical eye model (WAEM) based on the Liou-Brennan eye model. Off-axis, PA was determined as the defocus between the maxima on through-focus MTF curves for two orthogonal directions. The focusing frequency was adjusted to follow the peripheral decrease of neural cells sampling (C.A. Curcio et al., J. Comp. Neurol., 1990). Two IOL designs were evaluated: a standard monofocal aspheric (MA) and one designed to reduce PA (enhance peripheral vision, EPV) while retaining the same on-axis image quality (OIQ). OIQ and PA of both lens models were measured using WAEM. These results were compared with the clinical outcomes of a 6-month, prospective, randomized, paired-eye clinical study (30 subjects). Post-operatively, best corrected distance visual acuity (BCDVA) and peripheral refraction were measured in each eye using a computerized vision assessment system and an open field autorefractor, respectively.
Results :
The WAEM test results evidenced a significant reduction in PA at 20.0 degrees for the EPV lens model (-1.5D) and demonstrated similar MTF levels in white light for the two lens designs. The clinical study demonstrated a statistically significant mean reduction in PA with the EPV IOL of -1.6D (SD=1.51D, 20° nasal, p<0.0001) as compared to the MA IOL. Clinically measured PA was statistically significantly lower for EPV eyes at 20° and 30° in both the nasal and temporal fields. The BCDVA was similar for the two lens models for both photopic and mesopic with different contrast conditions (mean difference ≤-0.04 LogMAR).
Conclusions :
For two different lens designs, bench testing of IOLs in the WAEM demonstrated central image quality and PA results very similar to clinical measurements in pseudophakic subjects.
This abstract was presented at the 2024 ARVO Annual Meeting, held in Seattle, WA, May 5-9, 2024.