VEGF inhibitors and vitrectomy for diabetic vitreoretinopathy.

Diabetic retinopathy (DR) is one of the leading causes of blindness worldwide. Breakdown of the blood-retinal barrier in DR promotes accumulation of a high concentration of pre-retinal serum-derived chemoattractants, thereby stimulating cellular migration on the attached posterior hyaloid. This review assesses the role of intravitreal application of vascular endothelial growth factor (VEGF)inhibitors in combination with surgical removal of the vitreous. Vitrectomy with removal of the posterior hyaloids wash out the pocket of preretinal growth factors and enhance the diffusion of macro-molecules, including VEGF, insulin-like growth factor 1 or histamines, from the retinal into the vitreous cavity for further absorption through the anterior segment outflow pathways. The release of tractional forces induced by the vitreomacular traction or epiretinal membranes demonstrated a strong correlation to the reduction of retinal thickness in DME. Three techniques are described to remove the pre-retinal thickened and adherent vitreous: (1) delamination, (2) segmentation, and (3)en block dissection. A better visualization of remaining cortex vitreous or adjacent epiretinal membrane and safer removal may be achieved by a better intraoperative visualization using a variety of vital dyes to satin retinal tissue (chromovitrectomy). Anti-VEGF treatments may represent an alternative adjunctive treatment for DR.

Copyright 2009 S. Karger AG, Basel.