Accommodation causes with-the-rule astigmatism in emmetropes
Related Experiment Video
Updated: Oct 16, 2026

Simulating the Mechanics of Lens Accommodation via a Manual Lens Stretcher
Published on: February 23, 2018
M Tsukamoto1, K Nakajima, J Nishino
1Department of Ophthalmology, Nara Medical University, Kashihara, Japan.
Purpose:
To measure the changes in astigmatism when bilateral emmetropes accommodate.
Methods:
Bilateral emmetropes accommodative responses were measured with an improved photorefractometer PR-1100, which measured binocular refraction in all meridians simultaneously as a fixation target was shown in natural space.
Results:
The accommodative responses in the vertical meridian are greater than those in the horizontal meridian. In the horizontal meridian, the accommodative responses are less than the accommodative stimulus.
Conclusions:
When accommodating the majority of bilateral emmetropes show with-the-rule astigmatism and lag of accommodation in the horizontal meridian.
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