Peripheral vision can influence eye growth and refractive development in infant monkeys.

College of Optometry, University of Houston, TX 77204, USA.
Investigative Ophthalmology &amp Visual Science (Impact Factor: 3.66). 12/2005; 46(11):3965-72. DOI: 10.1167/iovs.05-0445
Source: PubMed

ABSTRACT Given the prominence of central vision in humans, it has been assumed that visual signals from the fovea dominate emmetropization. The purpose of this study was to examine the impact of peripheral vision on emmetropization.
Bilateral, peripheral form deprivation was produced in 12 infant monkeys by rearing them with diffusers that had either 4- or 8-mm apertures centered on the pupils of each eye, to allow 24 degrees or 37 degrees of unrestricted central vision, respectively. At the end of the lens-rearing period, an argon laser was used to ablate the fovea in one eye of each of seven monkeys. Subsequently, all the animals were allowed unrestricted vision. Refractive error and axial dimensions were measured along the pupillary axis by retinoscopy and A-scan ultrasonography, respectively. Control data were obtained from 21 normal monkeys and 3 infants reared with binocular plano lenses.
Nine of the 12 treated monkeys had refractive errors that fell outside the 10th- and 90th-percentile limits for the age-matched control subjects, and the average refractive error for the treated animals was more variable and significantly less hyperopic/more myopic (+0.03 +/- 2.39 D vs. +2.39 +/- 0.92 D). The refractive changes were symmetric in the two eyes of a given animal and axial in nature. After lens removal, all the treated monkeys recovered from the induced refractive errors. No interocular differences in the recovery process were observed in the animals with monocular foveal lesions.
On the one hand, the peripheral retina can contribute to emmetropizing responses and to ametropias produced by an abnormal visual experience. On the other hand, unrestricted central vision is not sufficient to ensure normal refractive development, and the fovea is not essential for emmetropizing responses.

  • Investigative ophthalmology & visual science. 01/2014; 55(10):6280.
  • [Show abstract] [Hide abstract]
    ABSTRACT: Purpose The purpose of this study was to investigate the optical zone power profile of the most commonly prescribed soft contact lenses to assess their potential impact on peripheral refractive error and hence myopia progression. Methods The optical power profiles of six single vision and ten multifocal contact lenses of five manufacturers in the powers −1.00 D, −3.00 D, and −6.00 D were measured using the SHSOphthalmic (Optocraft GmbH, Erlangen, Germany). Instrument repeatability was also investigated. Results Instrument repeatability was dependent on the distance from the optical centre, manifesting unreliable data for the central 1 mm of the optic zone. Single vision contact lens measurements of −6.00 D lenses revealed omafilcon A having the most negative spherical aberration, lotrafilcon A having the least. Somofilcon A had the highest minus power and lotrafilcon A the biggest deviation in positive direction, relative to their respective labelled powers. Negative spherical aberration occurred for almost all of the multifocal contact lenses, including the centre-distance designs etafilcon A bifocal and omafilcon A multifocal. Lotrafilcon B and balafilcon A seem to rely predominantly on the spherical aberration component to provide multifocality. Conclusions Power profiles of single vision soft contact lenses varied greatly, many having a negative spherical aberration profile that would exacerbate myopia. Some lens types and powers are affected by large intra-batch variability or power offsets of more than 0.25 dioptres. Evaluation of power profiles of multifocal lenses was derived that provides helpful information for prescribing lenses for presbyopes and progressing myopes.
    Contact Lens and Anterior Eye 08/2014; 38(1). · 2.00 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: To investigate the effect of low-addition soft contact lenses (CLs) with decentered optical design on the progression of myopia in children in a pilot study.
    Clinical ophthalmology (Auckland, N.Z.) 01/2014; 8:1947-56.

Full-text (2 Sources)

Available from
May 23, 2014