Evidence map›Paper›PMID 8981716›Full record

ArticleTransactions of the American Ophthalmological Society1996

The concentration of light in the human lens.

J C Merriam

Open access · greenAbstract read
In one paragraph

Article in Transactions of the American Ophthalmological Society, 1996. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 3 papers.

0numbers the graph read from it
0cells of the map it votes in
3citing papers in PubMed
0.9field-weighted citation impact, top 28% of its field
1 · What the graph read from it

What it found

Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.

The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.

Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

3 citing papers in PubMed, 32 citations in OpenAlex.

  1. Iron, the retina and the lens: a focused review.Experimental eye research · 2010
    Review
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4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

1 author.

J C Merriam

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

purposeThis thesis explores the idea that light energy, especially ultraviolet light, contributes to the unequal distribution of cataract around the world and to the development of cortical opacities.

methodsIn the first section, the thesis reviews historical concepts of the function of the lens and the nature of cataract, epidemiologic data on the global distribution of cataract, and clinical observations of the predominant location of cortical opacification. Second, computer ray tracings and geometric optics demonstrate the passage of light of varying angle of incidence within the lens. Third, two models of the human eye are used to study the refraction of light by the cornea and lens and illustrate the concentration of energy at the equatorial plane of the lens.

resultsCataract prevalence increases with proximity to the earth's equator, and cortical cataract is most common in the inferior and inferonasal lens. Theoretical studies and the eye models both demonstrate that the concentration of light within the lens increases with angle of incidence, and the eye models suggest that the inferior and inferonasal lens receives significantly more energy than other sections of the lens.

conclusionThe prevalence of cataract and exposure to ultraviolet energy both increase with decreasing latitude. The most common location of cortical cataract in the inferonasal lens is consistent with the greater dose of light energy received by this portion of the lens. These studies suggest that the global distribution of cataract and the development of cortical cataract are at least in part dependent on the dose of ultraviolet light received by the lens.

Indexed as

AnimalsCataractCorneaEnvironmental ExposureGeographyGlobal HealthHumansLens, CrystallineModels, AnatomicPrevalenceRadiation InjuriesRadiation Injuries, ExperimentalRefraction, OcularScattering, RadiationSunlightUltraviolet Rays

Identifiers

PMID8981716
PMCPMC1312115
OpenAlexW43296961

What OpenQuestion holds

Textmetadata
Read underepoch 390

Registered trials

None linked

Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.