Use of bovine pericardium (Tutopatch®) graft for surgical repair of deep melting corneal ulcers in dogs and corneal sequestra in cats.

OBJECTIVE: To evaluate the efficacy of bovine pericardium (BP) graft in the treatment of deep melting corneal ulcers in three dogs and corneal sequestra in three cats. PROCEDURE: Three dogs with keratomalacia affecting the deep third of the stroma and three cats with corneal sequestrum were evaluated and underwent surgery. Following keratectomy, BP material was placed into the keratectomy bed and sutured to the recipient cornea with 9/0 polyglactin suture material. Postoperative treatment with topical and systemic antibiotics, systemic nonsteroidal anti-inflammatory agents, and topical atropine was prescribed. Follow-up examinations were carried out 1, 2 weeks, 1 and 2 months after the surgery and consisted of a complete ophthalmic examination. Optical coherence tomography (OCT) was performed 1 and 2 months after the surgery in one dog and in one cat. RESULTS: At 1 week, corneal neovascularization was present around the BP graft in all cases. Four weeks after the BP graft, in two dogs and in all cats, the vascularization was regressing and the graft was integrated into the cornea, which was regaining transparency. Topical treatment with anti-inflammatory agents was then prescribed for 2 weeks. Two months after the surgery, 5 of 6 corneas in two dogs and three cats had healed with focal corneal scarring. The remaining dog had progression of the keratomalacia involving the deep BP graft that required additional surgery, but became blind. CONCLUSION: Bovine pericardium graft offers a promising option for surgical reconstruction of the cornea following keratectomy for the management of corneal ulcers and sequestra.

Effect of mydriasis induced by topical instillations of 0.5% tropicamide on the anterior segment in normotensive dogs using ultrasound biomicroscopy.

OBJECTIVE: To determine the effect of 0.5% tropicamide and the resultant mydriasis on the anterior segment in normotensive dogs using ultrasound biomicroscopy. PROCEDURE: Twenty-four dogs without ocular disease underwent ultrasound biomicroscopic examination of both the eyes under general anesthesia. Pharmacologic mydriasis was induced in the right eye of each dog by the topical instillation of 0.5% tropicamide. Ultrasound biomicroscopic examinations were performed and the anatomical parameters of the anterior segment were evaluated including the geometric iridocorneal angle (ICA) - formed by the plane of the iris root and the internal corneoscleral limbus - the width of the opening of the ciliary cleft (CC), the width of the mid-CC, the length of the CC, and the anterior chamber (AC) depth (distance between the corneal endothelium and the anterior lens capsule). RESULTS: Mydriasis resulting from the topical use of 0.5% tropicamide is associated with an increase in the geometric ICA and a decrease in the opening of the CC, without any effect on the width of the mid-CC, or on the length of the CC, or on the AC depth. CONCLUSIONS: Mydriasis induced by topical 0.5% tropicamide results in modification of the anterior segment which may influence the drainage of aqueous humor.