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Updated: Apr 1, 2026
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Quantification of Oculomotor Responses and Accommodation Through Instrumentation and Analysis Toolboxes
Published on: March 3, 2023
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A longitudinal study of accommodative changes in biometry during incipient presbyopia.
Deborah S Laughton1, Amy L Sheppard1, Leon N Davies1
1Ophthalmic Research Group, Life & Health Sciences, Aston University, Birmingham, UK.
Summary
Young adults experience changes in eye structure during accommodation, but the response per diopter remains stable before presbyopia. Increased lens stiffness likely causes presbyopia onset.
Area of Science:
- Ophthalmology
- Optometry
- Biomedical Optics
Background:
- Presbyopia, the age-related loss of accommodation, affects individuals before the typical onset age.
- Understanding longitudinal biometric changes is crucial for predicting presbyopia.
- Age-related ocular structural changes influence accommodative response.
Purpose of the Study:
- To longitudinally profile accommodative biometric changes in adults.
- To determine how age-related ocular structural changes impact accommodative response before presbyopia.
Main Methods:
- Twenty participants (34-41 years) were monitored over 2.5 years.
- Ocular biometry (anterior chamber depth, lens thickness, axial length) was measured using LenStar.
- Accommodative responses were assessed using a WAM 5500 Auto Ref/Keratometer with 0.00, 3.00, and 4.50 D stimuli.
Main Results:
- Accommodation reduced anterior chamber depth and increased lens thickness and axial length.
- After 2.5 years, the accommodative response and biometric changes per diopter decreased.
- Changes in anterior chamber depth, lens thickness, and axial length per diopter remained invariant with age.
Conclusions:
- The change in ocular biometry per diopter of accommodation is age-invariant before presbyopia.
- Findings support the Helmholtz theory of accommodation.
- Increased lenticular stiffness is implicated as a primary cause of presbyopia.
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