| Autor: |
Jeremy A, Guggenheim, Yen-Po, Chen, Elaine, Yip, Hélène, Hayet, Vladimir, Druel, Ling, Wang, Jonathan T, Erichsen, Alexandre R, Tumlinson, Boris, Povazay, Wolfgang, Drexler, Paul M, Hocking |
| Rok vydání: |
2011 |
| Předmět: |
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| Zdroj: |
Ophthalmicphysiological optics : the journal of the British College of Ophthalmic Opticians (Optometrists). 31(5) |
| ISSN: |
1475-1313 |
| Popis: |
Chicks developing experimentally-induced myopia show profound thinning of the choroid. We observed a wide range of choroidal thicknesses in a sample of normal chicks prior to their use in a pedigree-based study of form-deprivation myopia. Hence, we tested whether pre-treatment choroidal thickness predicted susceptibility to myopia.Retinal, choroidal and scleral thickness were measured using A-scan ultrasonography in normal White Leghorn chicks (n= 891) aged 4 days old, and again (n=498) after 4 days of monocular form-deprivation at age 8 days of age. Refractive error was assessed by retinoscopy. Relationships between pre-treatment choroidal thickness and other variables were investigated using general linear models and variance components analysis.Untreated 4 day-old male chicks had choroids approximately 10% thinner than females (p0.001), but sex explained2% of the overall variability in choroidal thickness. Axial eye length in these untreated chicks was not significantly associated with choroidal thickness (p=0.25). Moreover, pre-treatment choroidal thickness was not predictive of susceptibility to form-deprivation myopia (p=0.89). Heritability analysis suggested that at least 50% of the variation in pre-treatment choroidal thickness was determined by additive genetic effects (p0.001).Parental choroidal thickness is the major determinant of choroidal thickness in untreated 4-day old chicks. Despite choroidal thickness potentially being indicative of ongoing emmetropisation to innate refractive errors, in this study it was not predictive of subsequent susceptibility to form-deprivation myopia. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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