Use of type I bovine collagen membranes for treating deep and perforating corneal ulcers in brachycephalic dogs: a case series.

This retrospective study aimed to assess the effectiveness of lamellar keratoplasty using 200 μm type I bovine skin-derived collagen membranes for the treatment of deep and perforating corneal ulcers in dogs. Twelve cases involving dogs with descemetocele and/or ocular perforation demonstrated advanced corneal stromal damage and compromised eye integrity. Two hundred-micrometer (200 μm) type I bovine skin-derived collagen membranes were inserted into the corneal lesion, which was protected with a 360-degree conjunctival flap, followed by tarsorrhaphy. Evaluations were conducted on days 15, 30, and 60 via a self-designed V-injury score scale. By day 15, patients exhibited significant improvement, with stable intraocular pressure (IOP) and the absence of pain. All patients displayed episcleritis, moderate conjunctival inflammation, and diffuse corneal edema. The score was II in 10 dogs without limbal involvement but with moderate edema. Two dogs had a Grade III injury score with corneal edema exceeding 50% and moderate limbal involvement. By day 30, all patients had remodeled the corneal defect with stable IOPs, but three had moderate edema and superficial vascularization. On day 60, stable IOPs were observed, with four patients developing simple leucoma without involvement with the visual axis or active corneal alteration. The use of 200 μm type I bovine skin-derived collagen membranes, with a 360-degree conjunctival flap and temporary tarsorrhaphy, proves to be an excellent adjuvant in the healing process of deep and perforating corneal lesions in dogs. This combination facilitates corneal remodeling, reducing adverse scarring.