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Updated: Jun 12, 2026
05:14
Simulating the Mechanics of Lens Accommodation via a Manual Lens Stretcher
Published on: February 23, 2018
Axial length changes during accommodation in myopes and emmetropes.
Scott A Read1, Michael J Collins, Emily C Woodman
1Contact Lens and Visual Optics Laboratory, School of Optometry, Queensland University of Technology, Brisbane, Queensland, Australia. sa.read@qut.edu.au
Summary
Eye axial length (AXL) significantly elongates with accommodation, increasing with higher demands. This eye elongation during accommodation shows no significant difference between myopic and emmetropic young adults.
Area of Science:
- Ophthalmology
- Optometry
- Biomedical Optics
Background:
- Accommodation, the eye's ability to change focus, is crucial for clear vision.
- Understanding ocular biometric changes during accommodation is vital for myopia research and management.
Purpose of the Study:
- To investigate how accommodation influences axial length (AXL) and other ocular biometric parameters.
- To compare these accommodative effects in young adult myopic and emmetropic individuals.
Main Methods:
- Ocular biometry was measured in 40 young adults using optical low coherence reflectometry.
- Measurements were taken under three accommodation demands (0 D, 3 D, and 6 D).
- Subjects were classified as emmetropes (n=19) or myopes (n=21).
Main Results:
- Axial length (AXL) significantly increased with accommodation, with greater elongation at higher demands (3 D and 6 D).
- This axial elongation persisted even after correcting for lens thickness changes.
- No significant differences in AXL change magnitude were observed between myopic and emmetropic groups.
Conclusions:
- The eye exhibits significant axial elongation during accommodation, proportional to the accommodative demand.
- Myopic and emmetropic individuals show similar magnitudes of eye elongation in response to accommodation.
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