Plasma levels of angiogenic and angiostatic factors after panretinal photocoagulation for proliferative diabetic retinopathy

Panretinal photocoagulation in diabetic retinopathy improves oxygen saturation in the retina which results in regression of neovascularisation. This study is aimed at evaluating the plasma levels of angiogenic and angiostatic factors after panretinal photocoagulation for retinopathy. Thirty controls and 29 proliferative diabetic retinopathy subjects who were advised panretinal photocoagulation were recruited for the study. Plasma was collected both before and four weeks after the last dose of the therapy and analysed for angiogenic and angiostatic factors using ELISA technique. The plasma concentration of HIF-1α and VEGF were significantly decreased after laser therapy compared to baseline levels. The plasma concentration of MMP-9 and PEDF was increased significantly after photocoagulation. A significant improvement in the visual acuity was also observed following laser therapy. Panretinal photocoagulation significantly reduced plasma angiogenic and angiostatic factors. These factors may be used to assess therapeutic outcomes in proliferative retinopathy.