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Cited by 209Corneal surgery and disordersCorneal Surgery and TreatmentsCollagen: Extraction and Characterization

Collagen fibrils appear more closely packed in the prepupillary cornea: optical and biomechanical implications

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Boote, Craig, Dennis, Sally, Newton, Richard H., Puri, Hina, Meek, Keith M.·2003·Investigative Opthalmology & Visual Science
DOI 10.1167/iovs.03-0131
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Abstract

PURPOSE: The size and organization of stromal collagen fibrils influence the biomechanical and optical properties of the cornea and hence its function. How fibrillar structure varies with position across the cornea has not been fully characterized. The present study was designed to quantify the collagen fibril spacing and diameter across the normal human cornea and to relate this to the properties of the tissue. METHODS: Small-angle x-ray diffraction was used to map in detail the variation in fibril spacing and fibril diameter along orthogonal medial-lateral and inferior-superior meridians of five normal human corneoscleral discs. RESULTS: Mean fibril diameters remained constant across all corneas up to the limbus, whereupon a sharp increase was observed. However, mean fibril spacing across the central 4 x 3 mm (prepupillary) cornea measured 5% to 7% lower than in the peripheral cornea. CONCLUSIONS: Collagen fibrils in the prepupillary cornea appear to be more closely packed than in the peripheral cornea. Anisotropy in fibril packing across the cornea has potential implications for the transparency and refractive index of the tissue. Biomechanically, it is possible that the higher packing density of stress-bearing collagen fibrils in the prepupillary cornea is necessary for maintaining corneal strength, and hence curvature, in a region of reduced tissue thickness. By inference, these results could have important implications for the development of corneal models for refractive surgery.

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  • The decrease in transmittance outside the central 4 mm pre-pupillary cornea is attributed to the increase in fibril radius that occurs in the periphery of the cornea.

    “Theoretical calculations of light transmission (Doutch et al., 2008) attributed this to the increase in fibril radius that occurs in the periphery of the cornea (Boote et al., 2003).”

    From Corneal structure and transparency (2015) · cites this paper as Boote et al., 2003

    The Results (Fig. 5 and Table 2, near p. 2944) say fibril diameter remained constant from the corneal center to the limbus, with no significant difference between the prepupillary and peripheral zones. The reported increase occurs across the limbus, not within the peripheral cornea, so this paper contradicts the attributed explanation. (LLM, conf=0.93)

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Cites

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Research works printed but not linked: 30

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Authors
Boote, C., Dennis, S., Newton, R. H., Puri, H., & Meek, K. M.
Affiliations
Cardiff University (GB)
ORCID
Venue
Investigative Opthalmology & Visual Science
Publisher
Association for Research in Vision and Ophthalmology (ARVO)
Published
2003-07-01
Volume
44
Issue
7
Pages
2941
ISSN
  • 0146-0404 (ISSN-L)
  • 1552-5783
DOI
10.1167/iovs.03-0131
OpenAlex
W2095516478
Cited by
209
References
0
Citations by year
2026: 5 · 2025: 7 · 2024: 8 · 2023: 6 · 2022: 9 · 2021: 9 · 2020: 7 · 2019: 11 · 2018: 11 · 2017: 10 · 2016: 7 · 2015: 7 · 2014: 16 · 2013: 6 · 2012: 7
FWCI
4.60
Type
journal article
Language
en
Open access
Locations
  • Investigative Ophthalmology & Visual Science (publishedVersion)
  • PubMed (publishedVersion)
  • ORCA Online Research @Cardiff (Cardiff University) (acceptedVersion)
  • ORCA Online Research @Cardiff (Cardiff University) (submittedVersion)
Funders
  • Wellcome Trust
  • Medical Research Council (G0001033)
Topics
  • Health Sciences › Medicine › Radiology, Nuclear Medicine and Imaging › Corneal surgery and disorders
  • Health Sciences › Medicine › Radiology, Nuclear Medicine and Imaging › Corneal Surgery and Treatments
  • Physical Sciences › Materials Science › Biomaterials › Collagen: Extraction and Characterization
Keywords
corneal collagen fibrils, fibril diameter, corneal biomechanics, corneal transparency, refractive index, limbus, corneal curvature
MeSH terms
Biomechanical Phenomena, Collagen, Corneal Stroma, Humans, X-Ray Diffraction

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