Tai M Smith1, Shuko Suzuki1, Brendan G Cronin1, Mohammadreza Haghighatpanah1, Eugen B Petcu1,2, Christopher J Philippa3, Traian V Chirila1,4,5,6,7. 1. Queensland Eye Institute, South Brisbane, Queensland, Australia. 2. Griffith University School of Medicine, Menzies Health Institute, Gold Coast Campus, Queensland, Australia. 3. Department of Pathology, Gold Coast University Hospital, Southport, Queensland, Australia. 4. Queensland University of Technology, Science and Engineering Faculty, Brisbane, Queensland, Australia. 5. Australian Institute for Bioengineering and Nanotechnology, Brisbane, Queensland, Australia. 6. Faculty of Medicine, University of Queensland, Brisbane, Queensland, Australia. 7. Faculty of Science, University of Western Australia, Crawley, Western Australia, Australia.
Abstract
PURPOSE: An experimental study to demonstrate in animal eyelids that the controlled exposure of excised tarsal plate to ultraviolet-A radiation can induce a rigidification effect due to photochemical crosslinking of the constitutive collagen. METHODS: Excised strips of sheep tarsus were irradiated with ultraviolet-A rays (wavelength 365 nm) at low and high irradiances, in the presence of riboflavin as a photosensitizer, using radiation sources available for corneal collagen crosslinking procedure. The tensile strength and Young's modulus (stiffness) of irradiated and control samples were measured in a mechanical tester and analyzed statistically. Histologic examination of the specimens was carried out to evaluate the effect of radiation on the meibomian glands and collagen organization. RESULTS: Mechanical evaluation showed that irradiation induced both stiffening and strengthening of the tarsal plate specimens, and this effect was enhanced at the higher levels of irradiance. The changes in mechanical properties can be attributed to a process of photochemically induced crosslinking of tarsal collagen. Histology revealed no changes in the meibomian glands or in the fibrous collagen system of the tarsus. CONCLUSIONS: These findings indicate that irradiation of tarsal collagen leading to tissue stiffening could be a safe procedure for treating lax eyelid conditions in human patients.
PURPOSE: An experimental study to demonstrate in animal eyelids that the controlled exposure of excised tarsal plate to ultraviolet-A radiation can induce a rigidification effect due to photochemical crosslinking of the constitutive collagen. METHODS: Excised strips of sheep tarsus were irradiated with ultraviolet-A rays (wavelength 365 nm) at low and high irradiances, in the presence of riboflavin as a photosensitizer, using radiation sources available for corneal collagen crosslinking procedure. The tensile strength and Young's modulus (stiffness) of irradiated and control samples were measured in a mechanical tester and analyzed statistically. Histologic examination of the specimens was carried out to evaluate the effect of radiation on the meibomian glands and collagen organization. RESULTS: Mechanical evaluation showed that irradiation induced both stiffening and strengthening of the tarsal plate specimens, and this effect was enhanced at the higher levels of irradiance. The changes in mechanical properties can be attributed to a process of photochemically induced crosslinking of tarsal collagen. Histology revealed no changes in the meibomian glands or in the fibrous collagen system of the tarsus. CONCLUSIONS: These findings indicate that irradiation of tarsal collagen leading to tissue stiffening could be a safe procedure for treating lax eyelid conditions in humanpatients.
Authors: Sarah W DeParis; Angela Y Zhu; Shoumyo Majumdar; Jing Tian; Jennifer Elisseeff; Albert S Jun; Nicholas R Mahoney Journal: BMC Ophthalmol Date: 2019-12-16 Impact factor: 2.209
Authors: Sruti S Akella; Juan Liu; Yuan Miao; Roy S Chuck; Anne Barmettler; Cheng Zhang Journal: Transl Vis Sci Technol Date: 2021-04-29 Impact factor: 3.283
Authors: Shoaib Ugradar; Alan Le; Michael Lesgart; Robert A Goldberg; Daniel Rootman; Joseph L Demer Journal: Transl Vis Sci Technol Date: 2019-12-05 Impact factor: 3.283