CURRENT RESEARCHAge-Related Macular Degeneration: A Review of Experimental Treatments
Section snippets
Limitations of Current Treatment Modalities
Nonexudative AMD is much more common than exudative AMD and is commonly a precursor of exudative AMD. The nonexudative form involves a variety of presentations, including hard drusen, soft drusen, and geographic (areolar) atrophy of the RPE. Hard drusen are associated with localized dysfunction of the RPE, whereas soft drusen are associated with diffuse dysfunction of the RPE.21 Although more commonly associated with exudative AMD, severe visual loss can occur from nonexudative AMD,
Experimental Treatments for Exudative AMD
Because of the limited efficacy of laser photocoagulation and the small number of patients who are eligible for treatment, investigators are attempting to develop new modalities to treat CNVMs. These experimental treatment modalities can be classified into four major categories: photodynamic, pharmacologic, surgical, and radiation. Nearly all of these treatments have shown limited promise, and many have not been tested in animal models of choroidal neovascularization. In addition, many of these
Experimental treatment for nonexudative amd
All the treatments currently being pursued for AMD aim to destroy CNVMs, the end result of the exudative process. The treatment of the future, however, must be based on the pathogenesis of the disease at a stage well before CNVMs develop. In spite of much study, however, the pathogenesis of AMD remains unclear.
Summary
Age-related macular degeneration is the most common irreversible cause of severe visual loss in the USA. Laser photocoagulation, which represents the only treatment modality well studied in randomized, controlled prospective clinical trials, is limited in applicability and long-term control. Experimental modalities currently being evaluated show some promise but must undergo rigorous, prospective, randomized clinical trials before they are widely accepted. Most of these experimental treatments
Method of Literature Search
Literature selection for this article was based on a MEDLINE search covering the past 30 years for all articles, using key word combinations including age-related macular degeneration, macular photocoagulation study, photodynamic therapy, growth factor, interferon, thalidomide, steroid, surgery, radiation therapy, epidemiology, laser, and blood flow. For review of topics not yet published, literature selection was also based on review of abstracts from the annual meeting of the Association for
Acknowledgements
Supported, in part, by grants from Project Development Program, Research and Sponsored Programs, Indiana University at Indianapolis; The Indiana Lions’ Club; Research to Prevent Blindness, Inc.; and National Institutes of Health grant EY10801.
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