Evidence map›Paper›PMID 25503460›Full record

ArticleInvestigative ophthalmology & visual science2014

Independent active contraction of extraocular muscle compartments.

Andrew Shin, Lawrence Yoo, Joseph L Demer

Open access · bronzeAbstract read
In one paragraph

Article in Investigative ophthalmology & visual science, 2014. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 24 papers.

0numbers the graph read from it
0cells of the map it votes in
24citing papers in PubMed
1.7field-weighted citation impact, top 16% 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

24 citing papers in PubMed, 32 citations in OpenAlex.

  1. Functional Anatomy of Ocular Counter-Rolling in Superior Oblique Palsy.Investigative ophthalmology & visual science · 2025
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  7. Investigation of Selective Innervation of Extraocular Muscle Compartments.Investigative ophthalmology & visual science · 2023
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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

3 authors at 2 institutions in 1 country.

Andrew ShinDepartment of Ophthalmology, Stein Eye Institute, University of California, Los Angeles, Los Angeles, California, United States.
Lawrence YooDepartment of Ophthalmology, Stein Eye Institute, University of California, Los Angeles, Los Angeles, California, United States.
Joseph L DemerDepartment of Ophthalmology, Stein Eye Institute, University of California, Los Angeles, Los Angeles, California, United States.
University of California, Los Angeles · USYale University · US

Funding

Vision Research Core at UCLAP30EY000331 · NEI · UNIVERSITY OF CALIFORNIA LOS ANGELES · PI Gregory Darin Field, DAVID S WILLIAMS · 1985 to 2026
$16.8M
BIOMECHANICAL ANALYSIS IN STRABISMUS SURGERYR01EY008313 · NEI · UNIVERSITY OF CALIFORNIA LOS ANGELES · PI JOSEPH Louis DEMER · 1991 to 2026
$15.0M
NEI NIH HHS EY0331NEI NIH HHS EY08313NEI NIH HHS P30 EY000331NEI NIH HHS R01 EY008313
6 · The paper itself

Abstract

purposeIntramuscular innervation of horizontal rectus extraocular muscle (EOMs) is segregated into superior and inferior (transverse) compartments, whereas all EOMs are also divided into global (GL) and orbital (OL) layers with scleral and pulley insertions, respectively. Mechanical independence between both types of compartments has been demonstrated during passive tensile loading. We examined coupling between EOM compartments during active, ex vivo contraction.

methodsFresh bovine EOMs were removed, and one compartment of each was coated with hydrophobic petrolatum. Contraction of the uncoated compartment was induced by immersion in a solution of 50 mM CaCl2 at 38°C labeled with sodium fluorescein dye, whereas tensions in both compartments were monitored by strain gauges. Control experiments omitted petrolatum so that the entire EOM contracted. After physiological experiments, EOMs were sectioned transversely to demonstrate specificity of CaCl2 permeation by yellow fluorescence dye excited by blue light.

resultsIn control experiments without petrolatum, both transverse and GL and OL compartments contracted similarly. Selective compartmental omission of petrolatum caused markedly independent compartmental contraction whether measured at the GL or the OL insertions or for transverse compartments at the scleral insertion. Although some CaCl2 spread occurred, mean (±SD) tension in the coated compartments averaged only 10.5 ± 3.3% and 6.0 ± 1.5% in GL/OL and transverse compartments, respectively relative to uncoated compartments. Fluorescein penetration confirmed selective CaCl2 permeation.

conclusionsThese data confirm passive tensile findings of mechanical independence of EOM compartments and extend results to active contraction. EOMs behave actively as if composed of mechanically independent parallel fiber bundles having different insertional targets, consistent with the active pulley and transverse compartmental hypotheses.

Indexed as

Eye MovementsAnimalsBiomechanical PhenomenaCattleHumansMuscle ContractionOculomotor Musclesactive pulley hypothesiscompartmental hypothesisextraocular muscle

Identifiers

PMID25503460
PMCPMC4290554
OpenAlexW2329214424

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.