Quantification of Collagen Ultrastructure after Penetrating Keratoplasty – Implications for Corneal Biomechanics
| Autor: | Sally Hayes, Craig Boote, Steven Gardner, Jesper Hjortdal, Nicholas J. Terrill, Kim Nielsen, Thomas Sorensen, Erin Patricia Dooley, Keith M. Meek, Christina S. Kamma-Lorger |
|---|---|
| Jazyk: | angličtina |
| Rok vydání: | 2013 |
| Předmět: |
Anatomy and Physiology
medicine.medical_treatment lcsh:Medicine Scars Matrix (biology) Cornea 0302 clinical medicine X-Ray Diffraction Refractive surgery Biomechanics lcsh:Science skin and connective tissue diseases 0303 health sciences Multidisciplinary Chemistry Physics Anatomy Middle Aged Tissue Donors medicine.anatomical_structure Corneal Disorders Medicine Collagen medicine.symptom Research Article medicine.medical_specialty Tissue Mechanics Science Corneal Stroma Ocular Anatomy Biophysics Fibril 03 medical and health sciences Ocular System medicine Humans Biology Reduction (orthopedic surgery) Aged 030304 developmental biology lcsh:R Correction Surgery Ophthalmology 030221 ophthalmology & optometry Ultrastructure lcsh:Q RE sense organs Keratoplasty Penetrating |
| Zdroj: | PLoS ONE Boote, C, Dooley, E P, Gardner, S J, Kamma-Lorger, C S, Hayes, S, Nielsen, K, Hjortdal, J, Sørensen, T L-M, Terrill, N J & Meek, K M 2013, ' Quantification of collagen ultrastructure after penetrating keratoplasty-implications for corneal biomechanics ', PLOS ONE, vol. 8, no. 7, pp. e68166 . https://doi.org/10.1371/journal.pone.0068166 PLoS ONE, Vol 8, Iss 7, p e68166 (2013) PLoS ONE, Vol 8, Iss 9 (2013) |
| ISSN: | 1932-6203 |
| Popis: | Purpose: To quantify long-term changes in stromal collagen ultrastructure following penetrating keratoplasty (PK), and evaluate their possible implications for corneal biomechanics.\ud Methods: A pair of 16 mm post-mortem corneo-scleral buttons was obtained from a patient receiving bilateral penetrating keratoplasty 12 (left)/28 (right) years previously. Small-angle x-ray scattering quantified collagen fibril spacing, diameter and spatial order at 0.5 mm or 0.25 mm intervals along linear scans across the graft margin. Corresponding control data was collected from two corneo-scleral buttons with no history of refractive surgery. Wide-angle x-ray scattering quantified collagen fibril orientation at 0.25 mm (horizontal)×0.25 mm (vertical) intervals across both PK specimens. Quantification of orientation changes in the graft margin were verified by equivalent analysis of data from a 13 year post-operative right PK specimen obtained from a second patient in a previous study, and comparison made with new and published data from normal corneas.\ud Results: Marked changes to normal fibril alignment, in favour of tangentially oriented collagen, were observed around the entire graft margin in all PK specimens. The total number of meridional fibrils in the wound margin was observed to decrease by up to 40%, with the number of tangentially oriented fibrils increasing by up to 46%. As a result, in some locations the number of fibrils aligned parallel to the wound outnumbered those spanning it by up to five times. Localised increases in fibril spacing and diameter, with an accompanying reduction in matrix order, were also evident.\ud Conclusions: Abnormal collagen fibril size and spatial order within the PK graft margin are indicative of incomplete stromal wound remodelling and the long term persistence of fibrotic scar tissue. Lasting changes in collagen fibril orientation in and around PK wounds may alter corneal biomechanics and compromise the integrity of the graft-host interface in the long term. |
| Databáze: | OpenAIRE |
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