Corneal Ulcers in Dogs - Treatment with the Synthetic Polymer PBAT ; Úlceras de córnea em cães - tratamento com o polímero sintético PBAT

Background: Ulcerative keratitis is a common condition in dogs that, if untreated, can cause dog's loss of vision. The useof natural or synthetic polymer-based membranes has become a feasible alternative for the treatment of this injury due to their biodegradability, sustentability, non-toxicity and excellent mechanical properties as good resistance to impact and flexibility, being able to be used for medical applicances. This work aimed at evaluating the clinical effect of the poly(butylene-adipate-co-terephtalate) (PBAT) and thermoplastic starch (TPS) membrane as synthetic graft in lamelar kerato-plasty technique for the treatment of corneal ulcer in dogs.Materials, Methods & Results: This study included 6 dogs that, after pre-surgery exams, were underwent to lamelar keratoplasty with application of PBAT/TPS membrane on the injuried site. They were undergone to ophthalmological exams before the surgery (M0) as well as in the 3rd, 7th, 15th and 30th postoperative days (M3, M7, M15 and M30, respectively). Postoperative evaluations showed that blepharospasm was mild till M3, becoming absent in M30; while ocular secretion was slightly present till M7, being absent since then. Conjunctival hyperemy was intense in M0, diminishing gradually till M15. Clinical signs of corneal vascularization were observed from M7, becoming remarkably intense in M15. After membrane removal, corneal cicatrization was observed as well as the integrity of eye bulb's structure.Discussion: The clinical evolution of the animals submitted to the treatment with the membrane of PBAT/ TPS was similar to that reported by already established techniques, such as: free conjunctival graft and pediculated or with use of sardine scale and preserved renal capsule. In both, there was good corneal healing and there were no lesions of collanolytic pattern (melting type), no clinical signs of membrane extrusion The preference for the use of the PBAT/TPS membrane in the ratio 60:40 was due to the fact that it has a more malleable texture, that would be ...