Morphological evaluation of orbital implants in postenucleation reconstruction (an experimental study)

Abstract

Comparison of materials biocompatibility, design of different orbital implants and morphological condition of formed postenucleation stumps in an in vivo experiment. In the course of the study 24 rabbits were operated, divided into three comparable groups. Enucleation with primary implantation of an orbital implant was performed in all subjects. The following implants were used: polymeric orbital implant - in the main (experimental) group, polytetrafluorethylene insertion implant - in the control group 1, and silicone endoprosthesis - in the control group 2. We assessed features of the implantation process, implant design, general condition of the operated animals, condition of the postenucleation stumps, passive motility of the stumps, and reaction of the surrounding tissues to the implants. Performed surgeries did not negatively affect the general condition of the rabbits, and there was no significant local tissue reaction to the implants. The structural and design features of the implants used in the main group were found to be more convenient for implantation, ensured stable fixation and position in the orbit. Postenucleation stump motility was comparable in all groups during the early postoperative period. This parameter decreased at later follow-up times mostly in the control group 2. When extracting the implants, it was revealed that in the main group it had secure fixation to the orbital tissues and stable position, did not cause abundant proliferation of connective tissue. Pathomorphological examination revealed that tissue reaction to the implants was less prominent and was reversed soon with fine connective tissue capsule formation in the main group and control group 2. In the control group 1 tissue reaction increased progressively, and capsule formation was delayed. Polymeric implant is the most suitable orbital implant for postenucleation orbital reconstruction.