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Correction of Presbyopia by Monocular Bi-Aspheric Ablation Profile
Published on: September 20, 2024
Modified monovision with spherical aberration to improve presbyopic through-focus visual performance
Len Zheleznyak1, Ramkumar Sabesan, Je-Sun Oh
1Institute of Optics, University of Rochester, Rochester, New York 14624, USA. lelenz@optics.rochester.edu
Investigative Ophthalmology & Visual Science
|April 6, 2013
Summary
Modified monovision using spherical aberration enhances depth of focus and visual acuity compared to traditional monovision. This approach improves binocular vision by increasing interocular similarity in image quality.
Area of Science:
- Ophthalmology
- Vision Science
- Optical Engineering
Background:
- Monovision is a common correction for presbyopia, but it can limit depth of focus and binocularity.
- Spherical aberration (SA) is an optical aberration that can affect visual performance.
- Modifying monovision with induced SA may offer a way to improve through-focus visual performance.
Purpose of the Study:
- To investigate the impact of modifying monovision with monocularly induced spherical aberration (SA) on depth of focus (DoF).
- To enhance binocular through-focus visual performance by comparing modified monovision (MMV) with traditional monovision (TMV).
Main Methods:
- A binocular adaptive optics (AO) vision simulator was used to induce TMV and MMV in three subjects.
- TMV involved 1.5 D anisometropia; MMV included induced Zernike primary SA (± 0.2 and ± 0.4 μm).
- Monocular and binocular visual acuity (VA) and contrast sensitivity (CS) were measured through-focus with 4-mm pupils.
Main Results:
- MMV with positive SA improved intermediate VA by 1.5 lines compared to TMV; negative SA benefited near VA.
- MMV increased mean DoF to 3.5 D from 2.7 D with TMV.
- Binocular summation improved by 19% with MMV at 0.5 D, with no significant CS reduction at distance.
Conclusions:
- Modified monovision with induced SA improves through-focus VA and DoF compared to traditional monovision.
- Increased interocular similarity in image quality due to extended monocular DoF enhances binocular summation.
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