Selective Equatorial Sclera Crosslinking in the Orbit Using a Metal-Coated Polymer Waveguide

Journal Article · Tue Jun 18 00:00:00 EDT 2019 · Investigative Opthalmology & Visual Science

DOI:https://doi.org/10.1167/iovs.19-26709· OSTI ID:1626242

Kwok, Sheldon J. J. ^[1]; Forward, Sarah ^[2]; Wertheimer, Christian M. ^[2]; Liapis, Andreas C. ^[2]; Lin, Harvey H. ^[2]; Kim, Moonseok ^[2]; Seiler, Theo G. ^[3]; Birngruber, Reginald ^[4]; Kochevar, Irene E. ^[2]; Seiler, Theo ^[5]; Yun, Seok-Hyun ^[6]

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1. Massachusetts General Hospital, Boston, MA (United States). Harvard Medical School and Wellman Center for Photomedicine; Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States). Harvard-MIT Health Sciences and Technology
2. Massachusetts General Hospital, Boston, MA (United States). Harvard Medical School and Wellman Center for Photomedicine
3. Massachusetts General Hospital, Boston, MA (United States). Harvard Medical School and Wellman Center for Photomedicine; Institute for Refractive and Ophthalmic Surgery (IROC), Zurich, (Switzerland); Universität Bern, Bern, (Switzerland). Universitätsklinik für Augenheilkunde, Inselspital
4. Massachusetts General Hospital, Boston, MA (United States). Harvard Medical School and Wellman Center for Photomedicine; Universität zu Lübeck, Lübeck (Germany). Institut für Biomedizinische Optik
5. Institute for Refractive and Ophthalmic Surgery (IROC), Zurich, (Switzerland)
6. Massachusetts General Hospital, Boston, MA (United States). Harvard Medical School and Wellman Center for Photomedicine; Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States). Harvard-MIT Health Sciences and Technology

Purpose: Photochemical crosslinking of the sclera is an emerging technique that may prevent excessive eye elongation in pathologic myopia by stiffening the scleral tissue. To overcome the challenge of uniform light delivery in an anatomically restricted space, we previously introduced the use of flexible polymer waveguides. We presently demonstrate advanced waveguides that are optimized to deliver light selectively to equatorial sclera in the intact orbit. Methods: Our waveguides consist of a polydimethylsiloxane cladding and a polyurethane core, coupled to an optical fiber. A reflective silver coating deposited on the top and side surfaces of the waveguide prevents light leakage to nontarget, periorbital tissue. Postmortem rabbits were used to test the feasibility of in situ equatorial sclera crosslinking. Tensometry measurements were performed on ex vivo rabbit eyes to confirm a biomechanical stiffening effect. Results: Metal-coated waveguides enabled efficient light delivery to the entire circumference of the equatorial sclera with minimal light leakage to the periorbital tissues. Blue light was delivered to the intact orbit with a coefficient of variation in intensity of 22%, resulting in a 45 ± 11% bleaching of riboflavin fluorescence. A 2-fold increase in the Young's modulus at 5% strain (increase of 92% P < 0.05, at 25 J/cm²) was achieved for ex vivo crosslinked eyes. Conclusions: Flexible polymer waveguides with reflective, biocompatible surfaces are useful for sclera crosslinking to achieve targeted light delivery. We anticipate that our demonstrated procedure will be applicable to sclera crosslinking in live animal models and, potentially, humans in vivo.

• Research Organization: Brookhaven National Laboratory (BNL), Upton, NY (United States)
• Sponsoring Organization: USDOE Office of Science (SC); National Institutes of Health (NIH); US Air Force Office of Scientific Research (AFOSR)
• Grant/Contract Number: SC0012704; R01-EY025454; R41EY028820; P41-EB015903; FA9550-17-1-0277
• OSTI ID: 1626242
• Journal Information: Investigative Opthalmology & Visual Science, Vol. 60, Issue 7; ISSN 1552-5783
• Publisher: Association for Research in Vision and Ophthalmology
• Country of Publication: United States
• Language: English

Related Subjects

59 BASIC BIOLOGICAL SCIENCES
Ophthalmology
sclera
waveguide
crosslinking
myopia