Treatments for Age-related Macular Degeneration

Abstract

Age-related macular degeneration (AMD) is the most common cause of irreversible visual loss in the developed world. There are two types of AMD: dry and wet. The exact cause of the disease is unknown, but is thought to result from interplay of genetic and environmental factors. Smoking, hypertension and low intake and/or low levels of serum antioxidants are known risk factors for both forms. As yet there are no treatments available for the dry form of AMD. Smoking cessation and healthy lifestyles are important in the prevention of progression of AMD. Progression of early stages of AMD to advanced forms is slowed by regular intake of ocular nutritional supplements as found in the Age-Related Eye Disease Study (AREDS) Study. Recently, there have been significant breakthroughs in the treatment of wet or neovascular AMD, including photodynamic therapy (PDT), intravitreal injections of anti-vascular endothelial growth factor (anti-VEGF) drugs, including pegaptanib, ranibizumab and bevacizumab. Newer agents including aflibercept and anti-platelet-derived growth factor (anti-PDGF) compounds are under investigation. The current gold standard for treatment of wet AMD is intravitreal injections of ranibizumab. Combination therapy with PDT and anti-VEGF agents is useful especially in idiopathic polypoidal choroidopathy (IPCV) or when anti-VEGF monotherapy has failed. Rapid referral of patients with neovascular AMD is important as the visual outcome is dependent on the visual acuity at treatment. Diagnostic confirmation with retinal imaging, particularly fundus fluorescein angiography and optical coherent tomography, are required before treatment commencement. The new treatments for wet AMD are repetitive, and have significant service implications. These implications occur irrespective of which anti- VEGF agent is adopted. Visual rehabilitation is still important in the management of AMD.