Massive vascular endothelium growth factor (VEGF) expression in Eales' disease.

Background: Eales' disease is an idiopathic retinal vasculitic and vaso-occlusive process complicated by extensive retinal neovascularisation and vitreous hemorrhages. The great propensity to produce retinal neovessels is one of the particular aspects of the disease that deserves to be further investigated. We report a case of Eales' disease having evolved over more than three decades, with a typical clinical presentation in one eye, while the other eye had to be enucleated because of a terminal neovascular glaucoma, thus allowing pathological examination.

Methods: The functional right eye was treated by vitrectomy, cerclage, cryocoagulation and endolaser. The non-functional phthitic left eye was enucleated and submitted for histopathological and immunohistochemical examination using antibodies against vascular endothelial growth factor, T-cells, B-cells and Müller cells.

Results: Evolution was favourable in the operated right eye, following management of the inflammatory reaction. The histopathological examination of the left eye revealed an occlusion of the anterior chamber angle by rubeosis iridis, tractional retinal detachments, pre-, intra- and sub-retinal neovascular membranes, and vitrous hemorrhages. Diffuse positive anti-VEGF immunostaining was found at the level of the retinal neovascular membranes. The retina exhibited prominent Müller cell immunostaining, indicating extensive gliosis, and predominantly B cell infiltrates were found in the eye.

Conclusion: The present study indicates a close relationship between the prominent neovascular proliferation in Eales' disease and the intense expression of VEGF. The increased expression of VEGF, when compared to other conditions inducing neovascularisation, might explain the severity of neovascular growth and the propensity of repeated vitrous hemorrhages in Eales' disease.