الفهرس 
Tile: Panretinal laser photocoagulation versus targeted laser photocoagulation with and without intra-vitreal ranibizumab : A comparative study in the treatment of prolifera-tive diabetic retinopathy
ContantOnly 14 pages are availabe for public view
 |  | from | 126 |  |  |
| | | from | 126 | | |
Abstract
The pro-angiogenic cytokine vascular endothelial growth factor (VEGF) is considered the primary factor involved in neovascularization and the pathogenesis of PDR [5,6]. Increased levels of VEGF have been reported in the vitreous humor and fibrovascular tissues from eyes with PDR[7-12]. VEGF activates two tyrosine kinase receptors, VEGFR-1, and VEGFR-2. These receptors regulate physiological and pathological angiogenesis. VEGFR-2 is expressed mostly on vascular endothelial cells [13].Activation of VEGFR-2 stimulates endothelial cell proliferation, migration, and survival, as well as angiogenesis and microvascular permeability