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Effect of uncorrected astigmatism on vision
James S Wolffsohn1, Gurpreet Bhogal, Sunil Shah
1Aston University, School of Life and Health Sciences, Ophthalmic Research Group, Birmingham, United Kingdom. j.s.w.wolffsohn@aston.ac.uk
Journal of Cataract and Refractive Surgery
|February 22, 2011
Summary
Even mild uncorrected astigmatism significantly impairs vision and reading ability in older adults. This visual decline can negatively impact daily independence and overall quality of life.
Area of Science:
- Ophthalmology
- Optometry
- Vision Science
Background:
- Astigmatism is a common refractive error that can affect visual acuity.
- The impact of uncorrected astigmatism on older adults, particularly those with presbyopia, requires further investigation.
Purpose of the Study:
- To investigate the effects of varying degrees of uncorrected astigmatism on visual function in older adults.
Main Methods:
- Healthy presbyopic adults underwent induced astigmatism simulation using spectacle lenses.
- Visual acuity (distance and near), reading speed, light scatter, and driving reaction times were assessed.
- Subjective clarity of digital screens was also evaluated.
Main Results:
- Increasing uncorrected astigmatism significantly reduced distance and near visual acuity and reading speed.
- Subjective clarity ratings of digital screens decreased with higher astigmatism.
- Astigmatism orientation influenced visual performance, with 45 and 180-degree axes showing worse outcomes than 90 degrees.
Conclusions:
- Uncorrected astigmatism, even at low levels (1.00 D), significantly degrades vision in older adults.
- Failure to correct astigmatism can substantially diminish patients' independence and well-being.
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