Neovascular age-related macular degeneration (nAMD) is an eye condition affecting millions globally, particularly those over 60. This disease primarily impacts central vision, which is important for daily activities. Early detection and management are important, as it can lead to severe vision loss if left unaddressed. This article provides an overview of nAMD, covering its definition, causes, symptoms, diagnosis, treatment, and long-term outlook.
What is NAMD Disease?
NAMD stands for neovascular age-related macular degeneration, often referred to as “wet” AMD. This condition specifically affects the macula, a small, sensitive area in the center of the retina responsible for sharp, detailed central vision.
In nAMD, abnormal blood vessels grow abnormally beneath the macula. These new vessels are fragile and can leak fluid or blood, causing swelling, bleeding, and scarring that damages the macula. This leads to a deterioration of central vision. nAMD is a leading cause of vision loss for individuals over 60.
Causes and Risk Factors
nAMD develops from a combination of genetic and environmental factors. A family history of age-related macular degeneration increases risk, as certain genes are associated with the condition.
Age is a primary risk factor, becoming more common with advancing age. Lifestyle choices also contribute; for example, smokers are more likely to be affected by nAMD. Other contributing factors include obesity, gender (women may be at a higher risk), and race, with Caucasians being more commonly affected.
Symptoms and Diagnosis
Symptoms often involve changes in central vision. Common signs include blurred vision, difficulty with detailed work, and blind spots. Individuals may also experience metamorphopsia (straight lines appearing wavy or crooked), scotoma (areas of partial or complete vision loss), and difficulty distinguishing between colors.
Diagnosing nAMD typically involves a comprehensive eye examination. Regular eye tests, including a dilated retinal examination, can help identify nAMD. Optical coherence tomography (OCT) is a common imaging study used to detect fluid leakage and abnormal blood vessel growth, confirming nAMD. Some patients may be asymptomatic initially, highlighting the importance of regular monitoring.
Treatment and Management
Treatment focuses on preventing further vision loss and preserving existing vision. A common approach involves intravitreal anti-vascular endothelial growth factor (anti-VEGF) agents. These medications, including ranibizumab, aflibercept, and brolucizumab, are injected into the eye to inhibit the growth and leakage of abnormal blood vessels. Bevacizumab is also used off-label.
While anti-VEGF agents are effective, they often require frequent, sometimes monthly, injections and long-term treatment. To reduce the burden of frequent injections, newer anti-VEGF drugs and alternative treatment regimens are being explored, which may allow for longer intervals between treatments, potentially up to 12 or 16 weeks for some patients. Emerging treatments also include gene therapy, which aims to enable retinal cells to produce anti-VEGF proteins directly within the eye, and sustained-release implants that deliver medication over time. Faricimab is another treatment option, a bispecific antibody that targets both VEGF-A and angiopoietin-2, offering a different pathway for addressing nAMD.
Prognosis and Outlook
The prognosis for nAMD has improved significantly with the advent of anti-VEGF therapies, which can reduce the impact on vision compared to no treatment. However, nAMD is progressive, and vision may still deteriorate over time for some individuals. Untreated nAMD can lead to severe and rapid vision loss, potentially causing functional blindness.
Ongoing care and regular monitoring are important for managing nAMD and optimizing long-term outcomes. This includes consistent follow-up appointments with ophthalmologists to assess disease activity and adjust treatment as needed. While nAMD does not cause complete blindness, the loss of central vision can impact daily activities such as reading, driving, and recognizing faces, potentially affecting quality of life. Support groups and resources for patients and their families can provide valuable assistance in navigating the challenges associated with living with nAMD.