Neovascular age-related macular degeneration (AMD), often called wet AMD, is a serious eye condition that significantly impacts central vision. It is a leading cause of severe vision loss among older adults.
Understanding Neovascular AMD
Neovascular AMD is a type of age-related macular degeneration characterized by the growth of abnormal, fragile blood vessels beneath the macula. The macula, a small part of the retina, is responsible for sharp, detailed central vision and color perception. These newly formed vessels are often leaky, allowing fluid and blood to escape into the macula. This leakage damages light-sensing cells, leading to rapid deterioration of central vision.
This condition differs from dry AMD, which involves thinning of the macula and accumulation of drusen, leading to slower vision loss. While dry AMD is more common, neovascular AMD causes most severe vision loss cases associated with AMD due to direct vessel leakage. The formation of these aberrant blood vessels is largely driven by Vascular Endothelial Growth Factor (VEGF), a protein that stimulates new blood vessel growth.
Recognizing the Signs and Diagnosis
Individuals with neovascular AMD may experience several noticeable changes in their vision. Common symptoms include blurring of central vision. Straight lines may appear distorted or wavy (metamorphopsia), a sign of macular fluid. Some people also report a dark or blank spot in the center of their visual field.
Early detection of neovascular AMD is important for preserving vision. A comprehensive eye examination, including a dilated eye exam, is typically the first step. The Amsler grid test, a simple at-home test, involves looking at a grid of straight lines to detect distortions or missing areas. Advanced imaging techniques then confirm the diagnosis and assess damage.
Optical Coherence Tomography (OCT) is a non-invasive imaging technique that provides high-resolution cross-sectional images of the retina, detecting fluid and abnormal blood vessels. Fluorescein Angiography (FA) involves injecting a fluorescent dye, making leaking vessels visible. These tools help eye care professionals locate neovascular membranes, guiding treatment.
Treatment Approaches
The primary treatment for neovascular AMD involves anti-VEGF injections, which target the protein responsible for abnormal blood vessel growth. Medications such as aflibercept (Eylea) and ranibizumab (Lucentis) are commonly administered directly into the eye. These anti-VEGF agents inhibit VEGF, reducing new blood vessel growth and fluid leakage.
The injection procedure involves numbing the eye with anesthetic drops. Patients usually receive a series of initial injections, often monthly for several months. After this phase, injection frequency may be adjusted based on response, often transitioning to a “treat-and-extend” or “as needed” regimen. These treatments aim to stabilize vision and prevent further vision loss, though complete restoration of lost vision is generally not expected.
Other treatments, while less common, may be considered. Photodynamic therapy (PDT) involves injecting a light-sensitive drug (verteporfin), activated by a cold laser light, to seal off abnormal blood vessels. Laser photocoagulation, an older treatment, uses a hot laser to destroy abnormal blood vessels directly; however, it also destroys healthy tissue, creating a permanent blind spot. These alternatives are typically reserved for specific cases where anti-VEGF therapy is not suitable or effective.
Living with Neovascular AMD
Managing neovascular AMD requires ongoing commitment, including regular follow-up appointments with an ophthalmologist to monitor the condition and continue treatments. The frequency of visits and injections depends on the individual’s response and vision stability. Adherence to the prescribed schedule is important for maintaining visual outcomes and preventing disease progression.
For individuals with significant vision loss, low vision aids and rehabilitation services can be beneficial. These resources provide various tools, helping individuals maximize remaining vision and adapt to daily tasks. Occupational therapists can teach strategies to maintain independence and quality of life.
Lifestyle factors also support overall eye health, though they do not treat the underlying disease. A healthy diet rich in antioxidants and potentially AREDS2 supplements may support retinal health. Quitting smoking is recommended, as it is a significant risk factor for AMD progression. Protecting eyes from UV light also contributes to eye health. Addressing the emotional impact of vision loss through support groups or counseling can provide valuable coping mechanisms.