الفهرس 
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Abstract
Choroidal neovascularization (CNV) is a leading cause of severe irreversible visual loss, especially in patients older than 65 years of age. This pathological entity could be found in a number of diseases; more commonly in ARMD, degenerative myopia, angioid streaks and intraocular inflammations.CNV is an aberrant growth of blood vessels from the choriocapillaries which extend through Bruch’s membrane to proliferate under the retina, the RPE or both. This neovascular lesions can be so damaging to the structure and function of the retina, causing severe irreversible visual loss.The pathogenesis of CNV is complex. CNV may be initiated by a number of events, such as reduction in choriocapillaries blood flow, accumulation of lipid metabolic byproducts, oxidative stress and inflammation. In response to metabolic distress, the RPE and the retina produce factors, VEGF in particular, that act through a variety of mechanisms to cause CNV. VEGF has been implicated as a major angiogenic stimulus responsible for the formation of CNV.Fluorescein angiography (FA) and optical coherence tomography (OCT) scans are important tools used in the examination and management of CNV, and provide complementary information regarding lesions.FA is a powerful imaging modality, and gold standard for the differential diagnosis of CNV lesions, determining lesion characteristics and identifying the presence, location and size of the neovascular complex, which is composed of the choroidal neovascular lesion and its associated components.FA gives information about the integrity of the inner and outer retinal barrier and the presence of pathological vessels. FA can display lesion morphology data of CNV lesions. These neovascular lesions can be classified using fluorescein angiography into classic, minimally classic, and occult with no classic (occult only) CNV. OCT is good at detecting the presence of CNV in patients suspected of having new CNV. OCT is extremely useful in diagnosis and monitoring of CNV. OCT allows early diagnosis and helps in the decision-making process of the retreatment with anti-VEGF agents. OCT allows detailed description of CNV lesion, bringing significant contributions for progressing in understanding the CNV pathogenesis.OCT visualizes the arrangement and reflectivity of retinal and subretinal layers as well as the axial distribution of pathological fluid or tissue within the retina, the subretinal or sub-RPE space. The structural information provided by OCT is becoming a valuable diagnostic adjunct to FA.OCT and FA are complementary in examination and management of CNV lesions, but OCT is more valuable in ruling out the presence of subretinal neovascularization, assessment of macular edema associated with CNV and serial monitoring of response to treatment is best done with noninvasive imaging modalities such as OCT.