Abstract
Purpose :
Cornea fibrosis is a leading cause of blindness in ophthalmology. The treatment often required corneal keratoplasty, but it was not widely employed worldwide due to the lack of donor cornea and surgery complexity. A novel hyaluronic acid dendrimer hydrogel, HA-dendrimer, has been developed to effectively stabilize and seal corneal wounds temporarily. Our research focused on the long-term impact of using HA-dendrimer as a corneal substitute to repair and reconstruct the corneal structure.
Methods :
16 Rabbits (male/female) were divided into the following group: superficial anterior lamellar keratectomy (SALK), wound depth: 45-55% of the cornea, n=7; deep anterior lamellar keratectomy (DALK), wound depth 70-80% of the cornea, n=9; control eyes, n=4. HA-dendrimer was applied to the cornea and cross-linked with cobalt blue UV light for 90 seconds. We inspected the operated eyes weekly for corneal wound healing. Cornea structure and corneal re-epithelization were assessed by OCT and fluorescein staining at POD 15 days, one month, two months, three months, and then every three months after that. At POD 10 months, the rabbit's eye cornea was harvested for histopathological analysis. H&E staining, Masson’s chrome, cornea nerve staining by TUBB III, in vivo confocal microscope (IVCM), and transmission electron microscope (TEM) were performed and analyzed.
Results :
Near complete cornea regeneration was achieved by 6-10 months in animals with surgery. The operated cornea appeared as transparent as the contralateral eye in the SALK and DALK groups. OCT analysis confirmed the complete growth of cornea epithelium and stroma compared with the healthy cornea. In addition, near-normal corneal curvature was achieved in the operated eyes. Histology and TEM demonstrated that the cornea architecture was indistinguishable from the healthy cornea. Moreover, we found nerve innervation in the corneal anterior stroma and epithelium by both TUBB III staining and IVCM imaging, indicating the reconstructed cornea is completely functional with filling following lamellar keratectomy.
Conclusions :
HA-dendrimer covered the corneal wounds and promoted full cornea architecture reconstruction 6 to 10 months after lamellar keratoplasty. It suggests that the HA-dendrimer corneal substitute was biocompatible and acted as a scaffold for corneal regeneration. It can potentially be considered an alternative to anterior lamellar keratoplasty.
This abstract was presented at the 2024 ARVO Annual Meeting, held in Seattle, WA, May 5-9, 2024.