Purchase this article with an account.
David Troilo, Debora L. Nickla, Christine F. Wildsoet; Choroidal Thickness Changes during Altered Eye Growth and Refractive State in a Primate. Invest. Ophthalmol. Vis. Sci. 2000;41(6):1249-1258.
Download citation file:
© ARVO (1962-2015); The Authors (2016-present)
purpose. In the chick, compensation for experimentally induced defocus involves
changes in the thickness of the choroid. The choroid thickens in
response to imposed myopic defocus and thins in response to imposed
hyperopic defocus. This study was undertaken to determine whether
similar choroidal changes occur in the primate eye with induced
methods. Thirty-three common marmosets were used. Eyes in 26 monkeys served as
untreated control eyes, and eyes in 7 received 3 weeks of monocular lid
suture to induce changes in eye growth and refractive state. Refractive
errors were measured using refractometry and retinoscopy, and axial
ocular dimensions, including choroidal thickness, were measured using
high-frequency A-scan ultrasonography. Eyes were measured before the
lids were sutured and at frequent intervals after lid opening.
results. In the marmoset, choroidal thickness ranges from 88 to 150 μm and
increases significantly during the first year of life. Monocular lid
suture initially results in short, hyperopic eyes that then become
elongated and myopic. In these animals the choroids of both the
experimental and the fellow control eyes also increase in thickness
with age but additionally show interocular differences that vary
significantly with the relative changes in vitreous chamber depth and
refraction. In eyes that are shorter and more hyperopic than control
eyes the choroids are thicker, and in eyes that are longer and more
myopic than control eyes the choroids are thinner.
conclusions. In marmosets, the thickness of the choroid increases during postnatal
eye growth. Superimposed on this developmental increase in choroidal
thickness there are changes in thickness that are correlated with the
induced changes in eye size. These changes are small (<50 μm) in
comparison with those observed in the chick, contributing to less than
a diopter change in refractive error.
This PDF is available to Subscribers Only