Dependence of intraocular straylight on pigmentation and light transmission through the ocular wall

Berg, Thomas; Ijspeert, J. K.; Waard, Peter W.T. de

doi:10.1016/0042-6989(91)90057-c

Cited by 132 publications

(90 citation statements)

References 8 publications

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“…30 Another possible explanation for a protective effect of darker eye color is that lighter colored irides transmit twice as much light as darker colored irides, particularly at higher incident angles. 31 This relationship is probably not determined by pupil size or contraction velocity because iris color is not associated with pupil size 32 and blue irides contract more slowly and to a lesser extent than brown irides. 33 A greater transmission of light through the sclera of light than dark colored irides could also be involved.…”

Section: Discussionmentioning

confidence: 99%

“…33 A greater transmission of light through the sclera of light than dark colored irides could also be involved. 31 No other case-control study has assessed squinting as a child. Given the association between eye color and squinting as a child in these data, the association between choroidal and ciliary body melanoma and squinting may be more directly between eye color and exposure to solar radiation.…”

Section: Discussionmentioning

confidence: 99%

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Eye color and cutaneous nevi predict risk of ocular melanoma in Australia

Vajdic¹,

Kricker

Giblin

et al. 2001

Int. J. Cancer

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Ethnicity, cutaneous nevi and eye color are generally accepted risk factors for melanoma of the eye, although casecontrol studies have produced conflicting results. We sought to determine the constitutional risk factors for melanomas of the choroid, ciliary body, iris and conjunctiva in Australia. A population-based case-control study was conducted, with case ascertainment from a prospective national incidence survey and randomly selected community controls. Two hundred and ninety cases aged 18 -79 years and diagnosed between 1st January 1996 and 31st July 1998 were enrolled with 916 controls frequency matched by age, sex and State or Territory of residence. Risk of choroidal and ciliary body melanoma (n ‫؍‬ 246) was increased in people with grey (OR 2.9, 95% CI 1.5-5.5), hazel (OR 2.2, 95% CI 1.4 -3.7) and blue eyes (OR 1.7, 95% CI 1.0 -2.7) compared with brown eyes. Risk was also increased in those with 4 or more nevi on their back, those unable to tan, and those who squinted when outdoors as a child. Risk was reduced in people born other than in Australia and New Zealand (OR 0.7, 95% CI 0.5-1.0). Non-brown eye color was a risk factor for iris melanoma (n ‫؍‬ 25). No risk factors were identified for conjunctival melanoma (n ‫؍‬ 19). Eye color is the strongest constitutional predictor of choroidal and ciliary body melanoma, and may indicate a protective effect of melanin density at these sites. An independent association with cutaneous nevi suggests a role for other genetic factors.

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Section: Discussionmentioning

confidence: 99%

Section: Discussionmentioning

confidence: 99%

Eye color and cutaneous nevi predict risk of ocular melanoma in Australia

Vajdic¹,

Kricker

Giblin

et al. 2001

Int. J. Cancer

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“…Ocular melanin serves as a neutral density filter (0.37 log units) (26). Accordingly, with the absence of melanin in the albino, light entering the eye through the iris and pars plana is substantially increased (27). Thus, pigmented C57BL/6J and albino C57BL/6J c2j mice were housed from birth in either continuous darkness or under cyclic light; except for the mutated tyrosinase gene (c/c), these mice are genetically identical.…”

Section: A2e Accumulation In Albino and Pigmented Wild-type Mice Housmentioning

confidence: 99%

Photodegradation of retinal bisretinoids in mouse models and implications for macular degeneration

Ueda

Zhao

Kim

et al. 2016

Proc. Natl. Acad. Sci. U.S.A.

111

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Adducts of retinaldehyde (bisretinoids) form nonenzymatically in photoreceptor cells and accumulate in retinal pigment epithelial (RPE) cells as lipofuscin; these fluorophores are implicated in the pathogenesis of inherited and age-related macular degeneration (AMD). Here we demonstrate that bisretinoid photodegradation is ongoing in the eye. High-performance liquid chromatography (HPLC) analysis of eyes of dark-reared and cyclic light-reared wild-type mice, together with comparisons of pigmented versus albino mice, revealed a relationship between intraocular light and reduced levels of the bisretinoids A2E and A2-glycero-phosphoethanolamine (A2-GPE). Analysis of the bisretinoids A2E, A2-GPE, A2-dihydropyridinephosphatidylethanolamine (A2-DHP-PE), and all-trans-retinal dimerphosphatidylethanolamine (all-trans-retinal dimer-PE) also decreases in albino Abca4 −/− mice reared in cyclic light compared with darkness. In albino Abca4 −/− mice receiving a diet supplemented with the antioxidant vitamin E, higher levels of RPE bisretinoid were evidenced by HPLC analysis and quantitation of fundus autofluorescence; this effect is consistent with photooxidative processes known to precede bisretinoid degradation. Amelioration of outer nuclear layer thinning indicated that vitamin E treatment protected photoreceptor cells. Conversely, in-cage exposure to short-wavelength light resulted in reduced fundus autofluorescence, decreased HPLC-quantified A2E, outer nuclear layer thinning, and increased methylglyoxal (MG)-adducted protein. MG was also released upon bisretinoid photodegradation in cells. We suggest that the lower levels of these diretinal adducts in cyclic lightreared and albino mice reflect photodegradative loss of bisretinoid. These mechanisms may underlie associations among AMD risk, oxidative mechanisms, and lifetime light exposure.bisretinoid | visual cycle | retina | retinal pigment epithelium | macular degeneration

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“…Furthermore, the authors speculated that variations in fundus reflectance are also partly responsible for pigmentation dependence of straylight, which was later investigated more thoroughly by Vos and van den Berg. 1 The study of van den Berg et al 4 also showed that variation in pigmentation on the blue side of the eye color spectrum has much more influence on the straylight value than variation on the brown side. This can be understood by realizing that the contribution of straylight originating from fundus reflectance and eye wall translucency to the total amount of straylight is larger for less pigmented blue eyes than for well pigmented brown eyes.…”

Section: Introductionmentioning

confidence: 99%

“…Blue-eyed caucasians were found to have higher retinal straylight values compared to pigmented brown-eyed non-caucasians, leading to the conclusion that pigmentation is a source of variation in straylight in normal eyes. 2,3 Van den Berg et al 4 showed that this pigmentation dependence is partly caused by variations in transmission of light through the ocular wall. For dark-brown eyes of pigmented individuals transmission was found to be two orders of magnitude lower than for blue-eyed individuals.…”

Section: Introductionmentioning

confidence: 99%

Grading of Iris Color with an Extended Photographic Reference Set

Franssen

Coppens

Berg

2008

Journal of Optometry

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PURPOSE:To present a new iris pigmentation classification system based on comparison of iris pigmentation to a set of 24 standard eye photographs, with the aim of gaining on accuracy and on applicability for retinal straylight studies. METHODS: A reference set of 24 eye photographs was established by ranking the photographs from least (number 1) to most (number 24) iris pigmentation. Reproducibility was tested by grading a sample of 67 eye photographs with this reference set. RESULTS:The overall variation between observers was 1.46 on a scale of 0 to 25. CONCLUSION:The new method is promising to be more accurate than existing iris color classification systems in clinical situations where objective colorimetry-based systems are not available. The method may be useful to assess iris translucency and fundus reflectance as sources of variation in retinal straylight. RESUMEN OBJETIVO:Presentar un nuevo sistema de clasificación de la coloración del iris basado en la comparación de la pigmentación del iris con un conjunto de referencia formado por 24 fotografías de ojos, con el objetivo de lograr una mayor precisión y una mayor aplicabilidad del mismo en los estudios sobre la luz dispersa (parásita) que llega a la retina. MÉTODOS: Se ha establecido un conjunto de 24 fotografías de ojos, ordenadas de menor (fotografía número 1) a mayor (fotografía número 24) según la cantidad de pigmentación del iris. Para evaluar la reproducibilidad de este sistema, se utilizó una muestra compuesta por 67 fotografías de ojos. Varios observadores asignaron a cada una de las fotografías un valor de la escala de coloración, utilizando para ello el mencionado conjunto de referencia. RESULTADOS: La variación global entre observadores fue igual a 1,46, en una escala de 0 a 25. CONCLUSIONES: El nuevo método parece que puede llegar ser más preciso que los actuales sistemas de clasificación de la coloración del iris en aquellas situaciones de la práctica clínica donde no se dispone de sistemas objetivos basados en colorimetría. El método puede resultar útil para evaluar la translucidez del iris y la reflectancia del fondo de ojo como posibles orígenes de la variabilidad que existe entre sujetos de la cantidad de luz dispersa (parásita) que alcanza la retina. INTRODUCTIONIt is known from studies in the past that the amount of pigmentation in the eye wall and fundus influences the quality of the image on the retina of the normal human eye. Two main reasons were identified: part of the light projected on to the retina is not absorbed but is reflected back into the eye by the layers of the fundus, 1 and the fact taht the eye wall, including the iris, is not optically opaque. 2 Both effects depend on the amount of pigmentation in the fundus and the eye wall respectively. The light originating from fundus reflectance and eye wall translucency does not partake in proper image formation on the retina, but is scattered in the eye to create a veil of light over the retinal image. Together with scattered light originating from optical imperfect...

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Dependence of intraocular straylight on pigmentation and light transmission through the ocular wall

Cited by 132 publications

References 8 publications

Eye color and cutaneous nevi predict risk of ocular melanoma in Australia

Eye color and cutaneous nevi predict risk of ocular melanoma in Australia

Photodegradation of retinal bisretinoids in mouse models and implications for macular degeneration

Grading of Iris Color with an Extended Photographic Reference Set

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