The use of xenologous amniotic membrane to repair canine corneal perforation created by penetrating keratectomy

Abstract

This study was performed to evaluate the use of glycerol-preserved equine amniotic membrane as replacement for full-thickness corneal defects in dogs. Eighteen mixed-breed dogs were used. A perilimbal, full-thickness, 5 mm square corneal defect was created surgically, and a donor implant of equine amniotic membrane of the same size and shape sutured in place with 10-0 nylon simple interrupted sutures. Corneal edema was observed near the implant 24 h after surgery, but was absent after 1 week. Granulation tissue and corneal vascularization superficial to the implant were noticed on postoperative day 7, but were absent on day 30. Corneal vascularization persisted until the end of the experiment. There was no fluorescein retention by postoperative day 30. There was slight clearing of the corneal implant by postoperative 30, and slight pigmentation of the donor implant observed at postoperative day 180. An acute inflammatory process as well as fibroblasts were present at early postoperative stages. At postoperative day 60 there was no inflammatory cellular infiltrate, but fibroblasts and fibrosis were present. Corneal architecture was restored at the end of the experiment, with a layering of the epithelium-stroma-debris of amniotic membrane-stroma-endothelium present, and pigmentation and vascularization present in the deep layers of the cornea. Although vascularization indicated some degree of graft rejection, the clinical and histological evidence indicates that the xenologous amniotic membrane can be useful as a tectonic graft in the repair of full-thickness lesions of the cornea of dogs.

Preserved xenogenic amniotic membrane as a patch on the repair of superficial corneal ulcers in rabbits

“…It is accepted that the sutures were responsible for blepharospasm as its resolution occurred after the sutures' removal on the 7 th day after surgery (Barros et al, 1998). Additionally, blepharospasm lasted longer in TG animals because of the delayed wound healing in this group.…”

“…The preparation of the canine amniotic membrane followed guidelines from the literature (Pontes et al, 2010;Barros et al, 1998;Kim & Tseng, 1995), being aseptically collected from a healthy pregnant female dog carrying nearly-born fetuses. The membrane was separated from the chorion, cleaned with 0.9% sterile saline solution 3 at room temperature and stretched on a nitrocellulose paper with its epithelial surface facing up.…”

Effects of topical 0.2% Cyclosporine A on corneal neovascularization induced by xenologous amniotic membrane implantation into a corneal stroma micropocket of rats

“…In veterinary medicine its utility has been growing. For instance, it has been already used to repair full-thickness defects of the cornea of dogs (Barros et al 1998), generalized keratomalacia, ankyloblepharon, and after fibrous histiocytoma removal in two dogs and a cat (Barros et al 2005), to reconstruct corneal surface after excision of corneolimbal squamous cell carcinomas in nine horses (Olliver et al 2006), and to repair corneal ulceration and keratomalacia in three horses (Lassaline et al 2005).…”

Transplante de membrana amniótica canina criopreservada para cicatrização de córnea com deficiência de células límbicas em coelhos

“…Dentre os procedimentos cirúrgicos realizados na superfície corneana, as membranas biológicas, frescas ou conservadas em glicerina, são descritas para proteção mecânica de lesões profundas ou progressivas; dentre estas, há diversos relatos da utilização de peritônio canino (Garcia et al, 1996), pericárdio eqüino (Barros et al, 1997), membrana amniótica (Barros et al, 1998;Sampaio et al, 2006) e cápsula renal eqüina (Andrade et al, 1999).…”

“…Na medicina veterinária, a membrana amniótica conservada em glicerina foi descrita para ceratoplastia experimental em cães (Barros et al, 1998) e após ceratectomia para excisão de seqüestro corneano em felinos (Kavinski et al, 2002).…”