# Clinical and histopathological study of a hollow and posteriorly multiperforated polymethylmethacrylate implant in eviscerated rabbit eyes

## TL;DR

This study tested a special eye implant in rabbits and found it integrates well with surrounding tissues without causing infection or complications.

## Contribution

The novel hollow and multiperforated polymethylmethacrylate implant design promotes fibrovascular integration in an animal model.

## Key findings

- No infection, thinning, or implant exposure occurred in any rabbit during the study.
- Fibrovascular tissue migrated into the implant's posterior channels by day 7.
- Inflammatory response decreased over time with no multinucleated giant cells observed.

## Abstract

The study aimed to evaluate the clinical and tissue response to a hollow
polymethylmethacrylate orbital implant with a multiperforated posterior
surface in an animal model after evisceration.

Sixteen New Zealand rabbits had their right eye eviscerated. All animals
received a hollow polymethylmethacrylate implant 12 mm in diameter that is
multiperforated in its posterior hemisphere. The animals were divided into
four groups, and each one had the eye exenterated at 7, 30, 90, and 180 days
post-evisceration. Clinical signs were assessed daily for 14 days
post-evisceration and then every 7 days until 180 days. Inflammatory
pattern, collagen structure, and degree of neovascularization generated with
implant placement were analyzed with hematoxylin-eosin, picrosirius red, and
immunohistochemistry staining.

There were no signs of infection, conjunctival or scleral thinning, or
implant exposure or extrusion in any animal during the study. On day 7, the
new tissue migrated into the implant and formed a fibrovascular network
through the posterior channels. Inflammatory response reduced over time, and
no multinuclea­ted giant cells were found at any time.

Hollow polymethylmethacrylate orbital implants with a multiperforated
posterior surface enable rapid integration with orbital tissues by
fibrovascular ingrowth. We believe that this orbital implant model can be
used in research on humans.