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Updated: Jun 2, 2026

Correction of Presbyopia by Monocular Bi-Aspheric Ablation Profile
Published on: September 20, 2024
Outcomes of wavefront-guided laser in situ keratomileusis for hyperopia
Nancy J Keir1, Trefford Simpson, Natalie Hutchings
1Centre for Contact Lens Research, School of Optometry, University of Waterloo, 200 University Avenue West, Waterloo, Ontario N2L 3G1, Canada. njkeir@uwaterloo.ca
Purpose:
To determine the impact of wavefront-guided laser in situ keratomileusis (LASIK) for hyperopia on corrected distance visual acuity (CDVA), contrast sensitivity, and higher-order aberrations (HOAs).
Setting:
Centre for Contact Lens Research, University of Waterloo, Waterloo, Ontario, Canada.
Design:
Case series.
Methods:
This study comprised patients who had LASIK for hyperopia. The HOAs up to the 4th order (5.0 mm pupil) in right eyes were analyzed.
Results:
The study enrolled 31 patients. The preoperative mean values were sphere, +2.60 diopters (D) ± 1.15 (SD) (range +1.00 to +5.00 D); astigmatism, -0.87 ± 0.74 D (range 0.00 to -3.75 D); and spherical equivalent (SE), +2.16 ± 1.00 D (range +0.63 to +4.50 D). The postoperative refractive SE was within ±0.50 D in 71.0% of eyes. The uncorrected distance visual acuity was 20/20 or better in 87.2% of eyes. There was no significant change in CDVA or contrast sensitivity (all P>.05). There was a significant change in Zernike coefficients Z(0,4), Z(-1,3), Z(-3,3), and Z(3,3) (range of mean absolute change ± SEM: 0.092 ± 0.013 μm to 0.208 ± 0.018 μm; all P<.001). Coefficients Z(-1,3) and Z(3,3) increased and Z(0,4) and Z(-3,3) decreased in magnitude; each had a reversal of sign. The only significant postoperative association was between low-contrast CDVA and Z(0,4) (r=0.617, P<.001).
Conclusions:
Low-contrast CDVA after LASIK surgery for hyperopia was correlated with Z(0,4). There were no significant changes in CDVA or contrast sensitivity. The relative risk for losing low-contrast CDVA increased if more than 1 Zernike term had a sign change.
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