الفهرس 
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Abstract
Age-related macular degeneration (AMD) is the leading cause of irreversible blindness among elderly patients in developed countries. Age Related Macular Degeneration is classified into non-exudative (dry) and exudative (wet) types. Although exudative age-related macular degeneration represents only 10 to 15% of the overall prevalence of age-related macular degeneration, it is responsible for more than 75% of cases of severe visual loss resulting from age-related macular degeneration.
Risk factors for AMD include old age, smoking, sunlight exposure, nutritional factors (lack of dietary carotenoids), genetic factors and hypertension. Early detection for risk factors can help in delaying or stopping disease progression.
Symptoms of exudative AMD include: diminution of vision, distorted vision and central field defects. While ocular signs include: retinal, subretinal or choroidal hemorrhage, intra or subretinal fluid, RPE detachment and sometimes RPE tear.
Current diagnostic techniques for exudative AMD include: central visual field examination with Amsler grid, fundus imaging with: fluorescien angiography(FA), Indocyanine green (ICG) angiography, optical coherence tomography (OCT), fundus autoflurocence and scanning laser ophthalmoscope, as well as macular function tests such as fundus-related microperimetery and multifocal electroretinography (mfERG). FA is useful in detection of the type, size, location, and leakage characteristics of the CNV. Also it is essential for post-treatment assessment of patients. ICG angiography is a highly specialized technique for imaging choroidal vasculature. It does not replace FA; however ICG angiography plays an important role in diagnosis of occult CNV which appear poorly defined in FA. OCT performs high-resolution, cross-sectional imaging of ocular structures which is a valuable tool in morphological and quantitative pre and post-treatment assessment of exudative AMD patients. The role of non-invasive FAF is to identify accumulation of Lipofuscin (LF) within the RPE, which may predispose to neovascular AMD. Both fundus-related microperimetery and multifocal electroretinography (mfERG) can be used for assessment of macular function.
Treatment of exudative age-related macular degeneration has been revolutionized within the last few years with the introduction of intravitreal injection of anti-vascular endothelial growth factor (VEGF) agents. Previously popular destructive treatments, such as laser photocoagulation and photodynamic therapy have either been abandoned or used as an adjunct to pharmacotherapy. Monotherapy with intravitreal anti-VEGF agents remains the standard of care for exudative AMD. Despite the increase in vision after antivascular endothelial growth factor (VEGF) agents, they require repetitive and costly intravitreal injections that also carry the risks of complications. Combination treatments will affect multiple pathways simultaneously, and may prove more efficacious than monotherapy in refractory cases.
Although current therapies decrease leakage of CNV, yet, these therapies are only effective in treating the active stage of the CNV. Restoration of vision of a large number of patients with involuted CNV is warranted. For this purpose, tissue engineering techniques have been employed to reconstruct the subretinal anatomy. Gene therapy and new class of drugs that affect distinctly separate pathways in the pathogenesis of exudative AMD are expected to be available in the future. Combining current and future therapies, coupled with enhanced drug delivery technologies, may continue to enhance visual outcomes.