Abstract
Purpose :
Since the beginning of the development of implants to replace volume in the anophthalmic cavity in the last century, many different biomaterials were proposed but until now no one can be considered the gold standard, pushing new research in this field. The aim of this experimental study was to evaluate the biocompatibility of a new biomaterial to replace volume in enucleated or eviscerated anophthalmic socket of rabbits.
Methods :
This was an experimental, randomized study in which we used 21 rabbits of the species Oryctolagus cuniculus, of both sexes, aged 3 and 6 months. The enucleated or eviscerated rabbits received Nanoskin implants (Innovatecs®, São Carlos, Brazil), a cellulose produced by a bacteria (Acetobacter xylinum) using green tea as substrate. Implant of 10mm diameter/5mm of thickness were used placed in enucleated (G1) or eviscerated (G2) anophthalmic socket. They were clinically examined daily, sacrificed at 7(M1), 30(M2) and 90(M3) days after surgery and the material was removed and prepared for histological examination.
Results :
discrete signs of inflammation in the immediate postoperative period, with no evidence of infection or extrusion in any animal. However apparent reduction of volume during the trial period occurred. Histologically both groups were similar, with inflammatory cells (mainly monocytes and neutrophils), fibrin and hemaceas at 7 days postoperatively. The Nanoskin was presented as small spheres, color of pink, with small gaps between them and permeated by few inflammatory cells. These cells have changed over the study, at 30 days multinucleated giant cells and mature fibroblasts that permeate the implant were observed. At 90 days, the structure of the implant was disorganized, amorphous, with necrotic debris and ovoid areas covered with thin pink membrane that seemed to cluster, empty or filled with no cellular pink or gray material.
Conclusions :
Nanoskin caused inflammatory reaction leading to reabsorption and reduction of implant volume. New formulations should be studied in order to have a permanent product to repair the anophthalmic socket.
This is an abstract that was submitted for the 2016 ARVO Annual Meeting, held in Seattle, Wash., May 1-5, 2016.