Abstract
Purpose: :
To determine whether posterior vitreous detachment (PVD) affects the rate of progression of endophthalmitis in a rabbit model with Staphylococcus epidermidis.
Methods: :
New Zealand albino rabbits were innoculated with approximately 1 million bacteria (S. epidermidis) via intravitreal injection. The experimental arm of rabbits had received intravitreal injection of microplasmin enzyme (Thrombogenics, Dublin, Ireland) 400 microliters at least 7 days prior for enzymatic induction of posterior vitreous detachment, while the control arm received only bacterial inoculation. Rabbits were monitored for clinical symptoms of endophthalmitis, and B-scan ultrasonography was performed as infection developed. The eyes were studied histologically to compare the degree of retinal anatomic destruction approximately 1 day following bacterial inoculation.
Results: :
Clinical signs of endophthalmitis (corneal clouding and bulbar injection) developed in animals with enzymatic PVD at 1 day post-inoculation but not in the control group. B-scan demonstrated vitreous opacification in all inoculated eyes, and adhesions were evident between the vitreous and retina in a subset of both groups. Histology demonstrated a mild increase in architectural disruption in microplasmin-treated eyes compared to the control group.
Conclusions: :
Posterior vitreous detachment, as studied with microplasmin enzymatic induction in a rabbit model, may affect the speed with which exogenous bacterial endophthalmitis causes destruction of ocular tissue.
Keywords: endophthalmitis • bacterial disease • vitreous