This publication represents the summary of results of the doctoral thesis Presbyopia Corrections:Optical, Perceptual and Adaptational Implications presented at the Universidad Complutense deMadrid, Spain. Presbyopia, the physiological inability of the aging crystalline lens to accommodate forobjects at near distance, can be treated using a multitude of optical corrections. Systematicevaluation of the visual system’s ability to interact with these corrections will help in optimization oftheir performance. In this thesis we studied optical and perceptual performance of differentpresbyopic corrections such as alternating vision, monovision and simultaneous vision and the effectof adaptation on perceptual performances. We used custom-developed adaptive optics setup tomeasure and correct ocular aberrations and projected manipulated images simulating puresimultaneous vision corrections of different far/near energy profiles and near additions. We alsodeveloped and validated an on-bench and a hand-held simultaneous vision simulator to opticallysimulate pure or segmented simultaneous vision corrections. Psychophysical methods wereemployed to study the changes in perceptual quality and after-effects of adaptation. We performednumerical simulations to predict perceptual performance from the ocular aberrations of the subjects.We demonstrated that mechanism of adaptation to simultaneous vision is similar to that of bluradaptation, influenced mostly by retinal image contrast and that systematic changes in visual andperceptual performance influenced by multifocal design and testing distance. The ocular optics of thesubject’s eye correlated significantly with visual performance and was associated with theintersubject variability in performance. We found that a cyclopean locus for perception andadaptation, in subjects with different blur magnitude between eyes, influenced by the eyes withbetter optical quality. The internal code for blur was also influenced by the eye with better opticalquality, both in orientation and magnitude. Our results confirm that the existing optical solutionsshould be chosen based on the subjective needs and the ocular optics would be an ideal startingpoint to customize optical solutions of presbyopia for optimal performance. We also demonstratedthe usefulness of rapid assessment of perception to multifocal designs using the handheld, seethroughsimultaneous vision simulator.
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