Stephen R. Kaufman, MD, is Assistant Professor, Department of Ophthalmology, Case School of Medicine, Cleveland, Ohio.
Disclosure: The author states that he has no conflicting interests to disclose.
ABSTRACT
Age-related macular degeneration (ARMD) is the leading cause of legal blindness of Americans over age 65 years. Severe loss
of vision is usually due to exudative ARMD, of which there are about 200,000 new cases in the United States annually. Until
recently, only a small fraction of patients benefited from treatment, but advances in the early diagnosis of the disease and
major developments in therapy have substantially improved the prognosis of patients with ARMD. Because visual loss substantially
reduces quality of life, effective management of ARMD will have increasing public health importance as the population ages.
The American Academy of Ophthalmology recommends that people over age 65 years should have a comprehensive eye examination
every 1 to 2 years to check for cataracts, macular degeneration, glaucoma, and other conditions. Those who complain of difficulty
reading, driving at night, or adapting from sunlight to indoor lighting might have macular degeneration. Kaufman SR. Developments in age-related macular degeneration: Diagnosis and treatment. Geriatrics. 2009;64(3):16-19.
Key words: age-related macular degeneration, exudative, macula, non-exudative, retina
Drugs discussed: bevacizumab, pegaptanib, ranibizumab, triamcinolone, verteporfin
Loss of vision is one of the most feared and disabling consequences of aging. The American Academy of Ophthalmology recommends
that people over age 65 years should have a comprehensive eye examination every 1 to 2 years to check for cataracts, glaucoma,
macular degeneration, and other conditions.1 Primary care physicians (PCPs) should strongly urge their older patients to get thorough eye examinations by a qualified
provider at these 1 or 2 year intervals. PCPs should also note that patients who complain of difficulty reading, driving at
night, or having problems adapting from sunlight to indoor lighting might have age-related macular degeneration (ARMD).
ARMD is strongly associated with age, positive family history, and light skin pigmentation. Most patients have non-exudative
or "dry" ARMD, which often manifests as light yellow material called drusen located underneath the retina. These patients
usually have a modest loss of vision, but they are at risk for developing exudative ARMD, which tends to cause more damage.
Those patients with dry ARMD who lose reading vision usually have the atrophic form, in which there is typically bilateral
loss of the central retina (the macula) as well as the underlying choriocapillaris.
Figure 1 Retinal damage from exudative ARMD
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In exudative or "wet" ARMD, new blood vessels emanating from the choriocapillaris grow into the subretinal space. This neovascular
process damages the retina by several mechanisms (Figure 1). Leakage of serous and/or lipid exudate into the subretinal space
separates the retina from the choriocapillaris, making it more difficult for the retina to remove waste products and to obtain
nutrients. Recently, optical coherent tomography has demonstrated that many patients with exudative ARMD have intraretinal
edema, which damages the retina by a similar mechanism as seen in many patients with diabetic retinopathy. Hemorrhaging, when
it occurs, often results in permanent visual loss, because the iron in hemoglobin is toxic to the retina.
All forms of ARMD put central vision at risk, but they pose little if any threat to peripheral vision. Even patients with
advanced diseases usually retain sufficient vision to ambulate safely. Consequently, many patients with less than 20/200 vision
in both eyes (ie, legally blind) can maintain independent living, although they often need assistance with correspondence,
transportation, and certain household tasks.2
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