A comparison between dehydrated and cryopreserved heterologous corneal grafts for penetrating keratoplasty in dogs and cats

OBJECTIVE: To compare the efficacy of dehydrated and cryopreserved heterologous corneal grafts in the management of full-thickness corneal defects in cats and dogs. ANIMALS STUDIED: Sixty-five cats (81 eyes) and 42 dogs (51 eyes) with full-thickness corneal defects of different origin. MATERIALS AND METHODS: This prospective randomized trial included 132 animal eyes (81 feline and 51 canine) with different full-thickness corneal defects. Penetrating keratoplasty with cryopreserved and dehydrated corneal grafts was performed in 57 and 75 eyes, respectively. Follow-up lasted for 6 months. RESULTS: Optically clear cornea with mild scarring was achieved in 40.4% of cases (23/57 eyes) after cryopreserved and in 42.7% of cases (32/75 eyes) after dehydrated corneal grafting. Moderate scarring after cryopreserved and dehydrated corneal grafting was observed in 35.1% of cases (20/57 eyes) and 37.3% of cases (28/75 eyes), respectively. Severe scarring and corneal opacities with severe vision loss after cryopreserved and dehydrated corneal grafting developed in 22.8% of cases (13/57 eyes) and 18.7% of cases (14/75 eyes), respectively. In two groups of animals combined, the affected eyes were salvaged and visual function improvement of varying degree was achieved in 78.0% of cases (103/132 eyes). Transplant rejection warranted enucleation in 1.75% of cases (1/57 eyes) and 1.3% of cases (1/75 eyes) after cryopreserved and dehydrated corneal grafting, respectively. CONCLUSIONS: No statistically significant differences in clinical outcomes of penetrating keratoplasty with cryopreserved and dehydrated corneal grafts were observed. Dehydrated cornea may be considered a viable alternative to cryopreserved grafts for the management of full-thickness corneal defects.