ABSTRACT
BACKGROUND AND AIM: Ulcerative corneal lesions are common ocular affections encountered in veterinary ophthalmology, having a higher incidence in dogs with brachycephalic conformation. Prompt and effective diagnosis and repair are necessary to avoid corneal perforation and restore vision. Corneal wound healing is a complex phenomenon often resulting in vision impairment as a consequence of corneal fibrosis and pigmentation. The present study investigated the efficacy of decellularized and gamma-irradiated bovine omentum as an extracellular matrix scaffold in the reconstruction of extensive and full-thickness corneal defects, and the cytotoxic effects of mitomycin-C (MMC) to prevent corneal fibrosis and pigmentation. MATERIALS AND METHODS: Twelve injured corneas of eleven dogs irrespective of breed, age, and sex were randomly divided into Groups I and II, consisting of six corneas each. Under general anesthesia, corneal grafting with decellularized and gamma-irradiated bovine omentum was carried out in Group I, whereas Group II corneas underwent single time intra-operative application of topical MMC for 2 min before corneal grafting with the same material. Epithelialization of cornea and observations including corneal edema, neovascularization, the extent of pigmentation, corneal clarity, and scarring was recorded on days 7, 14, 21, and 60 postoperatively. RESULTS: All corneas in Group I showed early epithelialization by day 7 compared to Group II where the MMC delayed epithelialization in 50% of the corneas. Visual function scores improved greatly from 0.17±0.17 in Group II on the day of presentation to 1.0±00 by the end of the observation period compared to Group I (from 0.33±0.15 to 0.88±0.11). Although epithelialization and corneal healing were delayed, 50% of the corneas recovered with undetectable corneal scar and melanosis at the end of the observation period in Group II due to the anti-fibrotic effect of MMC. CONCLUSION: From the present study, it was concluded that re-epithelialization of the cornea was enhanced by corneal grafting with decellularized bovine omentum, and application of MMC was effective in delaying corneal fibrosis and pigmentation.
ABSTRACT
In regenerative medicine, despite the chances of graft-rejection, scaffolds prepared from extracellular matrices of various mammalian organs/tissues are widely used. Graft-assisted healing of full thickness skin-wounds is a major use of these bioscaffolds. Therefore, considering its prospective clinical use as a wound healing matrix, this study evaluated the healing potential of porcine cholecyst-derived scaffold (CDS) prepared by a non-detergent/enzymatic method for treating naturally occurring full thickness lacerated wounds in dogs. The CDS caused, in comparison with a commercial-grade bioscaffold prepared out of bovine dermal collagen (BDC), faster healing with respect to the wound healing parameters like peripheral tissue oedema, necrosis (amount and type), indurations, granulation tissue formation and the extent of re-epithelialisation. After 28 days of the treatment, the wound area (mean + SE) reduced from 27.60 ± 8.96 cm2 to 0.19+ 0.18 cm2 and 21.39 ± 5.48 to 6.59 ± 2.60 cm2 in CDS and BDC treated animals, with a reduction in wound sizes by 98.95 ± 2.09% and 54.53 ± 15.90 respectively. By this time, complete wound healing was observed in at least 75% of the former and 25% of the later groups. The CDS was deemed as a candidate bioscaffold for treating full thickness lacerated skin wounds in dogs.
