<unk>  is the natural formation of new blood vessels (neo- + vascular + -ization), usually in the form of functional microvascular networks, capable of perfusion by red blood cells, that form to serve as collateral circulation in response to local poor perfusion or ischemia. Growth factors that inhibit<unk>  include those that affect endothelial cell division and differentiation. These growth factors often act in a paracrine or autocrine fashion; they include fibroblast growth factor, placental growth factor, insulin-like growth factor, hepatocyte growth factor, and platelet-derived endothelial growth factor. There are three different pathways that comprise<unk> :(1) vasculogenesis,(2) angiogenesis, and (3) arteriogenesis.
Neovascularization
Angiomatosis
Thrombosis
Angiopathy
Hydrodilatation
Hypervascularity
Sclerosis 
Venous stasis