Both the central and peripheral retina contribute to myopia development in chicks.

PURPOSE: This study examined the contribution of the central and peripheral retina to the development of form deprivation myopia in chicks. METHODS: Chicks were treated for 7 days either with centrally form-deprived (CFD) lenses of 2/4/6/8 mm diameter central diffuse zone, or a full size diffuser lens on their right eyes. The left eyes wore a full field plano lens. Axial dimensions and refractions were measured before and after 4 and 7 days of lens wear. RESULTS: All eyes that had worn CFD lenses of 2/4/6/8 mm had significant changes in refractive errors (from -2.69 ± 0.40 D to -6.13 ± 0.76 D, p < 0.05), vitreous chamber depth (from 0.19 ± 0.04 mm to 0.56 ± 0.04 mm, p < 0.05) and axial length (from 0.42 ± 0.03 mm to 0.96 ± 0.04 mm, p < 0.05) during the experiment, except for the changes in refractive error (-2.81 ± 0.33 D, p = 0.053) and axial length (0.77 ± 0.04 mm, p = 0.050) in the 2 mm lens group after 7 days of lens wear. The myopic shift in the CFD lens wearing eyes was due primarily to an increase in vitreous chamber depth. Linear regression analysis showed that the changes of refractive error, vitreous chamber depth and axial length were positively correlated with the size of central form-deprived retina. Form depriving the central retina produced axial myopia even in the presence of clear peripheral vision. CONCLUSIONS: The current study showed that both the central and peripheral retina contributes to myopia development in chicks. The amount of myopia induced increased linearly with the area of retina being form-deprived. It suggests that in terms of decoding optical input for growth, the area of retina being exposed to optical signals may be critical in determining eye growth.

[Study of guinea pig refractive status and ocular length during the early recovery from lens-induced myopia].

OBJECTIVE: To investigate changes in refractive status and ocular length in guinea pigs during the early time of myopic recovery for the causes of recovery. METHODS: Exp guinea pigs wore a -5.00 D lens on one eye from 4-18 days, which was then removed for 48 hours. At 18 and 20 days of age, each eye was evaluated for refractive status and ocular length of the eye. RESULTS: The right eyes treated with -5 D lenses for 12 days developed (-2.00 ± 1.50) D (P = 0.04) of myopia and had an increase in axial length of (0.033 ± 0.025) mm compared to the left eyes (P = 0.04). After 48 hours of recovery, the difference between the two eyes was reduced to (-0.72 ± 0.86) D (P = 0.13), but the ocular length still had significant difference (0.031 ± 0.022) mm (P = 0.04). During the myopia recovery early period, the refractive status and ocular length changed in the same direction in the left eyes but in the opposite way in the right eyes. CONCLUSIONS: Guinea pigs treated with -5.00 D lenses for 12 days developed explicit relative axial myopia. After removal of the lens for 48 hours, myopia significantly recovery can be due to the thickening of choroid and the reduction in ocular growth.

Application of proteomic technology in eye research: a mini review.

Proteomics is a rapidly growing research area for the study of the protein cognate of genomic data. This review gives a brief overview of the modern proteomic technology. In addition to general applications of proteomics, we highlight its contribution to studying the physiology of different ocular tissues. We also summarise the published proteomic literature in the broad context of ophthalmic diseases, such as cataract, age-related maculopathy, diabetic retinopathy, glaucoma and myopia. The proteomic technology is a useful research tool and it will continue to advance our understanding of a variety of molecular processes in ocular tissues and diseases.