Corneal shape change during accommodation.

B K Pierścionek; A Popiołek-Masajada; H Kasprzak

doi:10.1038/eye.2001.246

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Corneal shape change during accommodation.

B K Pierścionek·A Popiołek-Masajada·H Kasprzak

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Abstract

PURPOSE: To investigate whether accommodation induces any changes in central corneal curvature. METHODS: Shape changes were measured on 14 subjects using a keratometer modified to enable a change in focus to occur without a change in vergence. All subjects were emmetropic and their ages ranged from approximately 20 to 28 years. RESULTS: In 11 of the 14 subjects a difference in central corneal curvature, of around 0.4 D in at least one principal meridian, was found when focus was changed between distant and near targets. In 9 subjects the curvature was greater for near focus in at least one meridian. In 5 subjects the change in one meridian was opposite in effect to what would be expected, i.e. the curvature was greater at distance than at near. CONCLUSION: The study suggests that accommodation may have some effect on corneal shape.

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Accommodation, Ocular Adult Cornea Female Fixation, Ocular Humans Male Journal Article Research Support, Non-U.S. Gov't

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B K Pierścionek, A Popiołek-Masajada, H Kasprzak. 2001. Corneal shape change during accommodation.. https://doi.org/10.1038/eye.2001.246

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