Choroidal neovascularisation. Coloured confocal light micrograph of a section through a human eye, showing laser-induced choroidal neovascularisation (CNV). CNV is the creation of new blood vessels (neovascularisation) in the choroid layer of the eye. Neovascularisation is frequently observed in individuals with age-related macular degeneration (AMD). In AMD patients, neovascularisation threatens vision and is often treated with drugs to slow or halt new blood vessel growth.