The effects of the relative strength of simultaneous competing defocus signals on emmetropization in infant rhesus monkeys

摘要: Purpose We investigated how the relative surface area devoted to more positive-powered component in dual-focus lenses influences emmetropization rhesus monkeys. Methods From 3 21 weeks of age, macaques were reared with binocular spectacles. The treatment had central 2-mm zones zero-power and concentric annular that alternating powers either +3.0 diopters (D) 0 D (+3 D/pL) or -3.0 (-3 D/pL). widths powered plano varied from 50:50 18:82 between groups. Refractive status, corneal curvature, axial dimensions assessed biweekly throughout lens-rearing period. Comparison data obtained monkeys full-field single-vision (FF+3D, n = 6; FF-3D, 10) 35 normal controls. Results median refractive errors for all +3 D/pL lens groups similar FF+3D group (+4.63 versus +4.31 +5.25 D; P 0.18-0.96), but significantly hyperopic than controls (+2.44 0.0002-0.003). In -3 monkeys, development was dominated by zero-powered portions lenses; animals (+2.94 +3.13 D) FF-3D (-0.78 0.004-0.006), 0.14-0.22). Conclusions results demonstrate even when make up only one-fifth a lens' area, is still myopic defocus. Overall, emphasize defocus distributed across visual field evokes strong signals slow eye growth primates.