Views

CrossRef citations to date

Altmetric

Sclera

Differential Regional Stiffening of Sclera by Collagen Cross-linking

Bola A. GawargiousDepartment of Integrative Biology and Physiology, University of California, Los Angeles, California, USAView further author information

Alan LeDepartment of Ophthalmology, University of California, Los Angeles, California, USA;Stein Eye Institute, University of California, Los Angeles, California, USA;Neuroscience and Bioengineering Interdepartmental Programs, University of California, Los Angeles, California, USAView further author information

Michael LesgartDepartment of Psychology, University of California, Los Angeles, California, USAView further author information

Shoaib UgradarDepartment of Ophthalmology, University of California, Los Angeles, California, USA;Stein Eye Institute, University of California, Los Angeles, California, USA

https://orcid.org/0000-0003-4479-3033 View further author information

Joseph L. DemerDepartment of Ophthalmology, University of California, Los Angeles, California, USA;Stein Eye Institute, University of California, Los Angeles, California, USA;Neuroscience and Bioengineering Interdepartmental Programs, University of California, Los Angeles, California, USA;Department of Neurology, University of California, Los Angeles, California, USA;David Geffen Medical School, University of California, Los Angeles, California, USACorrespondence[email protected]
View further author information

ABSTRACT

Purpose: Corneal collagen cross-linking by ultraviolet light activation of riboflavin has been used clinically to enhance corneal stiffness. We sought to determine if cross-linking differentially affects scleral regions.

Methods: Adjacent, parallel strips of sclera were cut from superolateral, superomedial, inferolateral, and inferomedial quadrants of posterior and equatorial sclera of 12 human cadaver eyes. One of each pair served as control while the other was cross-linked by immersion in 0.1% riboflavin and 365 nm exposure at 6 mW/cm² irradiance for 30 min. Behavior of strips was characterized using a microtensile load cell. Preloaded strips were imaged using orthogonally mounted cameras and optical coherence tomography to determine specimen dimensions including cross-sectional area. Tension was measured during 0.1 mm/s constant rate elongation.

Results: Young’s modulus (YM), the slope of the relationship relating tensile stress to strain, was calculated at 8% strain, and increased significantly after cross-linking (P < .001). In posterior sclera, mean (± standard error of mean, SEM) YM is increased in the superolateral, superomedial, inferolateral, and inferomedial quadrants by 46 ± 15%, 32 ± 11%, 67 ± 20%, and 53 ± 11%, respectively. In equatorial sclera, YM is increased by 139 ± 43%, 68 ± 27%, 143 ± 92%, and 68 ± 14%, respectively. The YM of pooled equatorial quadrants increased significantly more than that of the pooled posterior quadrants.

Conclusions: Scleral collagen cross-linking by ultraviolet activation of riboflavin differentially increases scleral YM more in the equatorial than posterior sclera, and most in the lateral, equatorial sclera. Cross-linking might be used to arrest progressive myopia or to prevent staphyloma formation.

KEYWORDS:

Disclosure Statement

None of the authors has a financial interest in any material related to this paper.

Additional information

Funding

USPHS EY008313 and an Unrestricted Grant from Research to Prevent Blindness to the Department of Ophthalmology.

Reprints and Corporate Permissions

Please note: Selecting permissions does not provide access to the full text of the article, please see our help page How do I view content?

To request a reprint or corporate permissions for this article, please click on the relevant link below:

Order Reprints Request Corporate Permissions

Academic Permissions

Please note: Selecting permissions does not provide access to the full text of the article, please see our help page How do I view content?

Obtain permissions instantly via Rightslink by clicking on the button below:

Request Academic Permissions

If you are unable to obtain permissions via Rightslink, please complete and submit this Permissions form. For more information, please visit our Permissions help page.

Differential Regional Stiffening of Sclera by Collagen Cross-linking

Information for

Open access

Opportunities

Help and information

Differential Regional Stiffening of Sclera by Collagen Cross-linking

ABSTRACT

Disclosure Statement

Additional information

Funding

Reprints and Corporate Permissions

Academic Permissions

Related research

To cite this article:

Download citation

Information for

Open access

Opportunities

Help and information

Keep up to date

Your download is now in progress and you may close this window

Login or register to access this feature