AMD Monitoring Comes Home: The Promise of Innovative Remote Tech
by: Jessica G. Lee, MD; Richard I. Kaplan, MD; Ronald C. Gentile, MD
Age-related macular degeneration (AMD) is the leading cause of severe vision loss in older Americans. AMD is a degenerative disease that affects the macula, or the central part of the retina, which has the highest density of photoreceptors, allowing for high-resolution central visual acuity. An estimated 1.75 million persons in the United States were diagnosed with AMD in 2000.
There are two major forms of AMD: nonexudative (“dry”) and exudative or neovascular (“wet”). Nonexudative AMD accounts for 85%-90% of all cases and neovascular AMD the remaining 10%-15%; however, the latter form is responsible for more than 80% of cases of severe vision loss or legal blindness (ie, visual acuity of 20/200 or worse) resulting from AMD. The main cause of vision loss in wet AMD is the development of choroidal neovascularization(CNV), which has been shown to occur in 18% of patients over 5 years.
In the early stages of AMD, patients may not experience any changes in their vision or symptoms, which may not be noticed until the disease has progressed or affected both eyes. Symptoms of AMD can vary and include blurred, distorted vision; visual scotomas; and decreased contrast and color sensitivity. With advanced dry AMD, the central visual loss and scotomas can occur over months to years. With wet AMD, the vision loss can be profound and occur within days to weeks as a result subretinal bleeding or fluid secondary to CNV.
With the advent of anti-vascular endothelial growth factor (anti-VEGF) therapy, treatment of wet AMD is now possible and is most effective when initiated promptly when CNV first develops.
Wet AMD is diagnosed through scheduled dilated eye examinations or, more often, depends on patients’ self-referral after visual symptoms develops. Early diagnosis and detection is key to prevent vision loss from wet AMD. The conversion from dry AMD to wet AMD can occur over days to weeks; thus, home monitoring systems can improve diagnostic and treatment paradigms of AMD.