Modeling the atrophy of retinal pigment epithelium

Abstract

Purpose: to develop easy-to make and reproducible models of retinal pigment epithelium atrophy (RPE) and retinal degeneration using two types of solution (0.9 % sodium chloride and bevacizumab) and to evaluate these models using clinical instrumental and pathomorphological studies. Material and methods. To create the two models, we used 60 New Zealand albino rabbits divided into 2 groups of 30 animals each (30 eyes). In group 1, 0.01 ml of 0.9 % sodium chloride solution was delivered into the subretinal space at a distance of 1–1.5 mm downwards from the optic disc forming a subretinal bladder, whilst group 2 received 0.01 ml of bevacizumab solution which contained 0.025 mg of the drug. Optical coherence tomography (OCT) and fundus autofluorescence imaging were performed in live rabbits’ eyes before and after the procedure on the 2nd, 7th, 14th, 24th, and 30th day using Heidelberg Spectralis™ SD-OCT (Heidelberg Engineering, Germany). The enucleated eyes were histologically evaluated 14 and 30 days after RPE atrophy modeling. Results. Two easily reproducible experimental models of RPE atrophy have been developed. Clinical and morphological indications of RPE atrophy are described. Histological analysis revealed a more aggressive action of 0.9% sodium chloride solution on the retina and the choroid as compared with the model obtained with a similarly delivered subretinal angiogenesis inhibitor. Conclusion. The obtained experimental models may be useful in investigating various types of RPE atrophy, including those arising from the use of angiogenesis inhibitors.

Keywords

• retinal pigment epithelium atrophy
• 0.9 % sodium chloride solution
• bevacizumab
• inhibitors of angiogenesis