Age-related macular degeneration: what can a family physician do?

Age-related macular degeneration (ARMD) is the most common cause of blindness in Canada, and, as the name suggests, its incidence increases rapidly with age. Atrophic maculopathy, one of the forms of ARMD, is associated with only mild to moderate visual loss but is not treatable. On the other hand, exudative maculopathy, another form, is characterized by the formation of neovascular membranes and causes acute visual disturbances; however, it is potentially treatable by means of laser photocoagulation. In symptomatic patients blood, lipids or serous fluid seen on funduscopic examination indicates occult neovascularization, even if no neovascular membrane is visible. In asymptomatic patients their age, the presence of soft drusen and the coarse pigmentary disturbance have the greatest correlation with the risk of neovascularization. Suitability for laser photocoagulation depends on the stage of exudative maculopathy, the duration of symptoms and the patient's visual acuity. Therefore, family physicians must know what the earliest symptoms are and how to identify patients at highest risk so that intervention in terms of education, screening and prompt referral to an ophthalmologist for confirmation and subsequent treatment can be instituted.