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Related Experiment Video

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Simulating the Mechanics of Lens Accommodation via a Manual Lens Stretcher

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Published on: February 23, 2018

Amplitude of accommodation and its relation to refractive errors.

Lekha Mary Abraham¹, Thomas Kuriakose, Viswanathan Sivanandam

¹Department of Ophthalmology, Christian Medical College, Vellore, India.

Indian Journal of Ophthalmology

|June 25, 2005

Summary

Myopes aged 35-44 years demonstrated a higher amplitude of accommodation (AA) compared to emmetropes and hypermetropes. This finding is significant for understanding refractive error impacts on visual function during peri-presbyopia.

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Area of Science:

Ophthalmology
Optometry
Vision Science

Background:

Presbyopia affects individuals aged 40 and above, impacting near vision.
Refractive errors, such as myopia and hyperopia, may influence the aging process of the eye's focusing ability.

Purpose of the Study:

To investigate the association between amplitude of accommodation and refractive errors in the peri-presbyopic population.
To compare the amplitude of accommodation across different refractive error groups in individuals aged 35-50.

Main Methods:

A study involving 316 participants aged 35-50 years with best-corrected visual acuity of 6/6.
Amplitude of accommodation (AA) was determined by measuring the near point of accommodation (NPA).
NPA measurements were adjusted using soft contact lenses for participants with significant refractive errors.

Main Results:

Significant differences in AA were observed between myopes and hypermetropes (P < 0.005) and myopes and emmetropes (P < 0.005) in the 35-39 age group.
In the 40-44 age group, significant differences in AA were found between emmetropes and hypermetropes (P < 0.0001), emmetropes and myopes (P < 0.01), and hypermetropes and myopes (P < 0.0001).
No significant differences in AA were noted in participants over 45 years old (P > 0.5).

Conclusions:

Myopic individuals between 35 and 44 years of age exhibited a greater amplitude of accommodation.
These findings suggest that refractive error influences accommodative ability during the onset of presbyopia.