The sensitivity of the chick eye to refractive defocus
The chick is commonly used as an animal model for human myopia and emmetropization. However one criticism of this model has been the very large refractive errors that are usually induced, either by visual deprivation or through the use of lenses to first impose focussing errors. This study sought to determine the threshold for compensatory responses to imposed defocus. We observed compensation in chick eyes fitted at hatching with +1D and -1D lenses (one over each eye). Consistent with the 2D interocular difference in refraction imposed, an average of 2.13D (SD 1.0D) of anisometropia and a 0.09 mm (SD 0.05 mm) interocular difference in vitreous chamber depth were recorded after five days of lens wear. The 1 D focusing errors imposed on individual eyes are not much greater in magnitude than the estimated depth of focus of the chick eye. The significance of these results for emmetropization are discussed.
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|Item Type:||Journal Article|
|Additional Information:||For more information, please refer to the journal’s website (see link) or contact the author. Author contact details: firstname.lastname@example.org|
|Keywords:||Adaptation, Physiological, Chickens/, physiology, Refractive Errors/, physiopathology, Animals, Chickens/growth & development, Eye/anatomy & histology, Eye/growth & development, Research Support, Non, U, S, Gov't|
|Subjects:||Australian and New Zealand Standard Research Classification > MEDICAL AND HEALTH SCIENCES (110000) > OPTOMETRY AND OPHTHALMOLOGY (111300)|
|Divisions:||Current > QUT Faculties and Divisions > Faculty of Health
Current > Institutes > Institute of Health and Biomedical Innovation
|Copyright Owner:||Copyright 1997 Elsevier|
|Deposited On:||14 Jun 2006 00:00|
|Last Modified:||15 Jan 2009 07:04|
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