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Published on: November 12, 2015
Sustained convergence, axial length, and corneal topography
Scott A Read1, Michael J Collins, Shiow-Huoy Cheong
1Contact Lens and Visual Optics Laboratory, School of Optometry, Queensland University of Technology, Brisbane, Queensland, Australia. sa.read@qut.edu.au
Summary
Sustained convergence did not significantly alter axial length in young adults. However, it caused minor but significant changes in corneal topography, particularly astigmatism.
Area of Science:
- Ophthalmology
- Optometry
- Vision Science
Background:
- Binocular vision and eye alignment are crucial for visual acuity.
- Understanding how visual tasks affect ocular structures is important for eye health.
Purpose of the Study:
- To investigate the impact of sustained convergence on axial length and corneal topography in young adults.
- To determine if convergence influences eye length or the cornea's shape.
Main Methods:
- Fifteen emmetropic young adults with normal binocular vision participated.
- Axial length and corneal topography were measured before and after wearing 8 and 16 prism diopter base-out lenses for 15 minutes.
- Eight subjects also had axial length measured during a convergence task.
Main Results:
- No significant changes in axial length were observed during or after convergence tasks (p > 0.6).
- Small but statistically significant changes in corneal topography occurred after sustained convergence.
- The 16 prism diopter base-out task induced significant changes in the corneal refractive power (J0) and superior corneal flattening.
Conclusions:
- Sustained convergence does not appear to significantly affect axial length in young adults.
- Convergence can induce minor, measurable changes in corneal topography, including astigmatism.
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