Natural latex graft in lamellar and penetrating sclerectomies in rabbits/Enxerto de latex natural na cicatrizacao de esclerectomias lamelar e penetrante em coelhos

The objective of study was to investigate the effects of natural latex with 0.1% of polylysine on lamellar and penetrating scleroctomies in rabbits. Two groups of twelve rabbits each (lamellar GI and penetrating GII) were studied. Scleral square incisions near the limbus were performed on the left eye of each animal. The latex biomembrane was fixed to the recipient sclera and it covered with a conjunctival flap. The clinical evaluations were followed for 60 days. Aplannation tonometry, binocular indirect ophthalmoscopy and slit-lamp biomicroscopy were performed during evaluation. Bright field microscopy and polarization microscopy were employed. Blepharospasm, graft infection, mucoid ocular discharge and chemosis were not observed in either treatment group. The conjunctival hyperemia varied from moderate to hardly noticeable. The postoperative IOP was not statiscally significant, comparing to the preoperative IOP, for GI and GII. The histopathology by polarization microscopy showed that the neoformed tissue was primarily dependent on adjacent vascularized tissues and was constituted by collagen type III. Both groups presented optimum graft adhesion to the receiving sclera. The natural latex biomembrane with 0.1% polylysine constitutes a new alternative for scleral reconstruction. Furthermore, this is a durable material, easy to obtain and manipulate. Key words: biomaterial, graft, healing, sclera, scleroplasty. Este trabalho teve como objetivo investigar os efeitos do latex natural com polilisina a 0,1% na cicatrizacao de esclerectomias lamelar e penetrante em coelhos. Foram estudados dois grupos de 12 coelhos (GI - lamelar e GII - penetrante). As esclerectomias foram realizadas no olho esquerdo de cada animal. A biomembrana de latex foi fixada a esclera receptora e foi recoberta com conjuntiva bulbar. As avaliacoes clinicas foram realizadas durante 60 dias. Para tal, empregaram-se a tonometria de aplanacao, a oftalmoscopia indireta binocular e a biomicroscopia em lampada de fenda. Realizou-se analise histopatologica das escleras em microscopia de luz e sob luz polarizada. Nao houve blefarospasmo, secrecao ocular mucoide, quemose ou sinais de infeccao do enxerto em ambos os grupos. A hiperemia conjuntival variou de moderada a tenue. Nao houve diferenca estatisticamente significativa entre a pressao intraocular do periodo pos-operatorio e do periodo pre-operatorio, para o GI e o GII. A histopatologia por microscopia de polarizacao demonstrou que o tecido ne