On the second stage , as abnormal new blood vessels ( neovascularisation ) form at the back of the eye as a part of proliferative diabetic retinopathy ( PDR ) , they can burst and bleed ( vitreous hemorrhage ) and blur vision , because the new blood vessels are weak .
As new blood vessels form at the back of the eye as a part of proliferative diabetic retinopathy ( PDR ) , they can bleed ( ocular hemorrhage ) and blur vision .