الفهرس 
. Structure and function of the human retinaOnly 14 pages are availabe for public view
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Abstract
Age-related macular degeneration (AMD) is a degenerative disorder of the macula for those ages 65 and above. It is a global disease that causes blindness, is becoming increasingly prevalent, and has no effective cure. AMD is classified into an early stage and a late stage. Early AMD includes eyes with drusen and eyes with hyperpigmentation or hypopigmentation of the RPE. Late AMD includes eyes with geographic atrophy and eyes with neovascular manifestations of the disease.
Fluorescein angiography (FA) is an essential tool in management and diagnosis of AMD. It is useful in confirming the presence of CNV and to define its size and borders so that treatment can be undertaken in a precise manner. Indocyanine green angiography (ICG) is a highly specialized technique for imaging choroidal vasculature. It has several advantages over FA including lower toxicity and infrared fluorescence for better penetration through pigment, serosanguineous fluid, and a thin layer of blood. Optical coherence tomography (OCT) is a new imaging modality that performs high-resolution, cross-sectional imaging of ocular structures. The structural information provided by OCT is becoming a valuable diagnostic adjunct to FA and ICG. In particular, OCT is a valuable tool to monitor the treatment effects associated with photodynamic therapy (PDT) as well as intraocular pharmacologic therapy in neovascular AMD.
Although AMD continues to be a relevant threat to visual function, there is exciting progress in the development of new and effective treatments for this condition. Destructive methods such as laser photocoagulation and submacular surgery do not play a role any more among treatment options. PDT monotherapy has proven to slow progressive vision loss in patients with subfoveal and relatively small lesion types, but improvement in visual function may not be achieved with PDT alone.
The development of anti-VEGF agents has introduced an important advance in the therapeutic spectrum of AMD. The encouraging results from clinical trials and preclinical evaluations are changing our goals from simply preventing moderate or severe vision loss to the aim of restoring and improving vision in our patients. However, not all anti-VEGF strategies are the same: Pegabtanib, which addresses only the VEGF isoform 165, is just able to slow visual acuity loss. Ranibizumab, however, which blocks all VEGF isoforms, appears to improve visual function in a significant proportion of patients. Off-label therapy is not only an ethical, but also a legal issue even though bevacizumab appears to be a safe and effective substance as well. But as long as prospective, randomized trials are missing, a clinical approval is not realistic.
Anti-inflammatory compounds such as steroids have long been used to suppress not only inflammation, but also associated angiogenesis. Unfortunately, profound side effects associated with glucocorticoid activity of many of these compounds make long term administration of effective dosing levels problematic with certain patients. Combination approaches are another promising perspective. Adjunctive methods may improve the efficacy of monotherapy strategies in term of visual outcome or in respect to retreatment needs. The use of low-vision aids may allow many of patients with central visual impairment continue to function independently.
Within the next decade, we hope that continued advances in clinical research will help restore vision in patients with this severely debilitating disease and also prevent development of the disease in those at risk.