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Adaptation to Progressive Additive Lenses: Potential Factors to Consider
Tara L Alvarez1, Eun H Kim2, Bérangère Granger-Donetti3
1Department of Biomedical Engineering, New Jersey Institute of Technology, Newark, NJ, 07102, USA. tara.l.alvarez@njit.edu.
Scientific Reports
|June 2, 2017
Summary
Certain visual adaptation abilities, like vergence facility and phoria adaptation rate, help predict if individuals will successfully adapt to progressive addition lenses (PALs). This is crucial for managing age-related vision changes.
Area of Science:
- Ophthalmology and Vision Science
- Neuroscience
- Human Aging Research
Background:
- Presbyopia is an age-related condition affecting near vision.
- Most individuals adapt to progressive addition lenses (PALs), but some struggle.
- Understanding adaptation mechanisms is key to improving visual aid outcomes.
Purpose of the Study:
- To investigate the correlation between visual adaptation abilities and successful adaptation to PALs.
- To identify specific vergence and phoria modification parameters predictive of PALs adaptation.
Main Methods:
- Experiment 1: Quantified convergence modification using a double-step paradigm in 16 presbyopes.
- Experiment 2: Measured phoria adaptation magnitude and rate in 31 incipient presbyopes before and after one month of PALs wear.
- Statistical analysis included linear regression between vergence parameters and PALs adaptation.
Main Results:
- Presbyopic PALs adapters showed significantly greater convergence peak velocity modification than non-adapters (p < 0.03).
- Incipient presbyopic PALs adapters exhibited a significantly higher rate of phoria adaptation and greater vergence facility than non-adapters (p < 0.03).
Conclusions:
- Vergence facility and the rate of phoria adaptation are significant predictors of successful PALs adaptation.
- These parameters may offer clinical value in identifying patients likely to experience difficulties with PALs.
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