TL;DR
Wet macular degeneration, also known as neovascular age-related macular degeneration (AMD), affects millions of people worldwide and is one of the leading causes of vision loss in adults over 50.
This guide provides you with essential information about this serious eye condition, from early warning signs to the latest breakthrough treatments available.
What is wet macular degeneration?
Wet macular degeneration is the more severe form of age-related macular degeneration, accounting for approximately 10-15% of all AMD cases. Despite being less common than dry AMD, wet macular degeneration is responsible for about 90% of severe vision loss associated with macular degeneration.
The condition occurs when abnormal blood vessels grow beneath the macula – the central portion of the retina responsible for sharp, detailed vision.
These blood vessels are fragile and prone to leaking blood and fluid, which damages the delicate photoreceptor cells and leads to rapid vision deterioration.
The anatomy behind wet macular degeneration
To understand wet macular degeneration, it’s important to know how your eye works:
- The macula: This small, highly sensitive area at the centre of your retina is packed with cone cells that enable you to see fine details, read, drive, and recognise faces. When the macula is damaged, your central vision becomes blurred or distorted, whilst peripheral vision typically remains intact.
- Bruch’s membrane: This thin layer separates the retina from the underlying blood supply. With age, this membrane can become damaged, allowing abnormal blood vessels to penetrate through.
- VEGF (Vascular Endothelial Growth Factor): This protein plays a crucial role in wet AMD by promoting the growth of new blood vessels. When VEGF levels increase abnormally, it triggers the formation of the leaky blood vessels characteristic of wet macular degeneration.
Wet vs. dry macular degeneration: Key differences
While both forms affect the same area of the eye, they progress very differently:
Wet macular degeneration
- Rapid progression (vision can deteriorate within weeks or months)
- Caused by abnormal blood vessel growth
- Accounts for 10-15% of AMD cases
- Responsible for 90% of severe AMD-related vision loss
- Treatable with various interventions
- May develop suddenly in people with dry AMD
Dry macular degeneration
- May progress to wet AMD in some cases
- Slow progression (may take years to advance)
- Caused by gradual breakdown of light-sensitive cells
- Accounts for 85-90% of AMD cases
- Currently has limited treatment options
Related read: Dry vs Wet Macular Degeneration
Early warning signs and symptoms of wet macular degeneration
Recognising the early signs of wet macular degeneration is crucial for preventing severe vision loss. The condition can develop rapidly, sometimes within days or weeks, making prompt medical attention essential.
Primary symptoms
- Visual distortions (Metamorphopsia): Straight lines may appear wavy, bent, or curved. This is often one of the first noticeable symptoms and occurs due to fluid buildup beneath the macula.
- Central vision loss: You may notice a dark, blurry spot in the centre of your vision that gradually expands. This scotoma can make reading, driving, and facial recognition increasingly difficult.
- Decreased colour perception: Colours may appear less vibrant or washed out, particularly in your central vision.
- Difficulty with fine detail: Activities requiring sharp vision, such as threading a needle, reading small print, or recognising faces, become challenging.
- Reduced night vision: You may experience increased difficulty seeing in low-light conditions.
- Contrast sensitivity issues: Distinguishing between similar shades or seeing objects against similar backgrounds becomes more difficult.
The Amsler grid test
One of the most effective tools for monitoring macular health is the Amsler grid – a simple test you can perform at home. This grid consists of straight horizontal and vertical lines with a central dot. If you have wet macular degeneration, some lines may appear wavy, distorted, or missing entirely.
How to use the Amsler grid:
- Hold the grid at normal reading distance (approximately 14-16 inches)
- Cover one eye and focus on the centre dot
- Note any areas where lines appear wavy, blurred, or missing
- Repeat with the other eye
- Report any changes to your eye care professional immediately
Understanding the causes and risk factors of wet AMD
Whilst the exact cause of wet macular degeneration remains under investigation, researchers have identified several key risk factors and contributing mechanisms.
Non-modifiable risk factors
- Age: The most significant risk factor, with the condition primarily affecting people over 50. Risk increases substantially after age 60.
- Genetics: Family history plays a crucial role. Having a parent or sibling with macular degeneration significantly increases your risk. Specific genetic variants, including mutations in the CFH, ARMS2, and C3 genes, have been associated with increased susceptibility.
- Race: Caucasians have a higher risk of developing macular degeneration compared to other ethnic groups.
- Gender: Women may have a slightly higher risk than men, possibly due to longer life expectancy.
Modifiable risk factors
- Smoking: Perhaps the most significant modifiable risk factor. Smokers are 2-4 times more likely to develop macular degeneration, and the risk increases with the number of cigarettes smoked daily and the duration of smoking.
- Cardiovascular disease: Conditions affecting blood circulation, including high blood pressure, high cholesterol, and heart disease, can increase AMD risk.
- Diet: Diets low in antioxidants, omega-3 fatty acids, and specific nutrients like lutein and zeaxanthin may contribute to AMD development.
- Obesity: Being significantly overweight, particularly having a high body mass index, correlates with increased AMD risk and progression.
- UV light exposure: Prolonged exposure to harmful UV rays without proper eye protection may contribute to retinal damage over time.
Diagnostic process and advanced testing
Diagnosing wet macular degeneration requires comprehensive eye examination and specialised testing to assess the extent of the condition and plan appropriate treatment.
Comprehensive eye examination
Your eye care professional will conduct a thorough examination including:
- Visual acuity testing: Measures how well you can see at various distances using standardised eye charts.
- Dilated eye examination: After dilating your pupils with special drops, your eye doctor can examine the back of your eye, including the macula, for signs of abnormal blood vessels, bleeding, or fluid accumulation.
- Amsler grid testing: In-office testing to detect metamorphopsia and central vision defects.
Advanced diagnostic imaging
- Fluorescein angiography (FA): This test involves injecting a fluorescent dye into your arm, which travels through your bloodstream to the blood vessels in your eye. Special photographs are then taken to identify leaking blood vessels and guide treatment planning.
- Indocyanine green angiography (ICG): Similar to fluorescein angiography but uses a different dye that can better visualise deeper blood vessel abnormalities.
- Optical coherence tomography (OCT): This non-invasive imaging technique uses light waves to create detailed cross-sectional images of your retina, allowing doctors to measure retinal thickness and detect fluid accumulation with remarkable precision.
- OCT angiography (OCTA): A newer technology that can visualise blood vessels in the retina without the need for dye injection, providing detailed information about abnormal vessel growth.
Current treatment options for wet macular degeneration
The landscape of wet macular degeneration treatment has evolved dramatically over the past two decades, offering patients significantly better outcomes than previously possible.
Anti-VEGF injections (the gold standard)
Anti-VEGF (vascular endothelial growth factor) injections, such as ranibizumab (Lucentis), aflibercept (Eylea), and bevacizumab (Avastin, used off-label), which help reduce abnormal blood vessel growth and leakage, represent the cornerstone of wet AMD treatment.
How anti-VEGF therapy works: These medications block the action of VEGF, the protein responsible for stimulating abnormal blood vessel growth. By inhibiting VEGF, these treatments can:
- Stop or slow the growth of abnormal blood vessels
- Reduce fluid leakage
- Help preserve existing vision
- In some cases, improve vision
Current anti-VEGF medications
- Ranibizumab (Lucentis): FDA-approved specifically for wet AMD, typically administered monthly initially, then as needed based on individual response.
- Aflibercept (Eylea): Often allows for less frequent injections (every 6-8 weeks initially), making it convenient for many patients.
- Bevacizumab (Avastin): Originally developed for cancer treatment, it’s used off-label for wet AMD and has shown similar efficacy to other anti-VEGF drugs at a significantly lower cost.
- Brolucizumab (Beovu): A newer anti-VEGF option that may allow for extended treatment intervals in some patients.
Photodynamic therapy (PDT)
Whilst less commonly used today due to the success of anti-VEGF therapy, photodynamic therapy remains an option for specific cases. This treatment involves:
- Injection of a light-sensitive drug (verteporfin) into the bloodstream
- Activation of the drug using a specific wavelength of light directed at the abnormal blood vessels
- Selective destruction of abnormal vessels while preserving normal retinal tissue
Laser therapy
Traditional laser photocoagulation is now rarely used for wet AMD due to the risk of creating permanent blind spots. However, it may still be considered in very specific circumstances where other treatments are not suitable.
Treatment protocols and monitoring
- Loading phase: Most patients begin with monthly injections for the first 3-4 months to achieve maximum therapeutic effect.
- Maintenance phase: Treatment frequency is then adjusted based on individual response, with some patients requiring injections every 4-6 weeks, whilst others may extend to 8-12 weeks between treatments.
- Treat-and-extend protocol: Many eye care professionals now use this approach, gradually extending the time between injections based on disease activity whilst maintaining treatment efficacy.
Breakthrough treatments and future therapies
The field of wet macular degeneration treatment continues to advance rapidly, with several promising therapies in development or recently approved.
Gene therapy
Gene therapies could offer hope for long-term control of wet AMD with one-time treatments, representing a paradigm shift from repeated injections to potentially permanent solutions.
ABBV-RGX-314 (also known as RGX-314) is being developed as a novel one-time gene therapy for the treatment of neovascular (wet) age-related macular degeneration (wet AMD). This innovative treatment works by:
- Delivering a gene that enables the eye to produce its own anti-VEGF protein
- Potentially eliminating the need for repeated injections
- Offering long-term vision preservation with a single treatment
Current clinical trials are showing promising results, with some patients maintaining stable vision for extended periods without additional treatments.
Port delivery system (PDS)
The Port Delivery System represents an innovative approach to delivering anti-VEGF medication continuously to the eye. This surgically implanted device:
- Provides sustained drug delivery over 6+ months
- Reduces injection frequency dramatically
- Maintains consistent drug levels in the eye
- Offers improved quality of life for patients
Novel drug targets
Researchers are investigating new therapeutic targets beyond VEGF:
- Complement system inhibition: Targeting the complement cascade, which plays a role in inflammation and tissue damage in AMD.
- Anti-angiogenic combinations: Combining different anti-angiogenic approaches for enhanced efficacy.
- Neuroprotection: Developing treatments that protect retinal neurones from damage, potentially preserving vision even when blood vessel abnormalities persist.
Emerging research areas
Researchers determined in mice that an enzyme related to cell growth and division is a culprit in the blood vessel invasion in the back of the eye that causes blurred central vision in wet AMD. This research into telomerase as a treatment target represents just one of many innovative approaches being investigated.
Living with wet macular degeneration: practical strategies
Whilst medical treatment is essential, adapting your daily life to accommodate vision changes can significantly improve your quality of life and independence.
Vision rehabilitation services
- Low vision specialists: These professionals can assess your remaining vision and recommend specific aids and strategies to maximise your functional vision.
- Occupational therapists: Specialising in low vision, they can help you adapt your home environment and daily activities to maintain independence.
- Orientation and mobility training: For those with significant vision loss, this training helps develop safe navigation skills.
Assistive technology and devices
Magnification aids
- Handheld magnifiers for reading
- Stand magnifiers for hands-free viewing
- Electronic magnification systems (CCTV systems)
- Smartphone apps with magnification features
Lighting improvements
- Task-specific lighting for reading and detailed work
- Adjustable LED lamps with high colour rendering
- Reduction of glare through proper window treatments
Computer and digital aids
- Screen magnification software
- High-contrast display settings
- Voice recognition software
- Audio books and reading apps
Home safety modifications
- Lighting: Install bright, even lighting throughout your home, particularly in stairways, bathrooms, and work areas.
- Contrast enhancement: Use high-contrast materials – dark objects on light backgrounds and vice versa—to improve visibility.
- Organisation: Maintain consistent organisation of household items and avoid moving furniture unnecessarily.
- Safety devices: Install grab bars, non-slip mats, and other safety equipment to prevent falls.
Lifestyle modifications and prevention strategies
Whilst you cannot completely prevent wet macular degeneration, certain lifestyle choices can significantly reduce your risk and potentially slow progression.
Nutritional strategies
Based on extensive clinical trials, the AREDS2 formula has been shown to reduce the risk of advanced AMD progression:
Diet recommendations
- Leafy green vegetables: Rich in lutein and zeaxanthin, which accumulate in the macula and may provide protective benefits
- Omega-3 fatty acids: Found in fatty fish, these may support retinal health
- Antioxidant-rich foods: Berries, citrus fruits, and colourful vegetables provide protective compounds
- Zinc-rich foods: Oysters, beef, and beans support retinal function
Lifestyle modifications
- Smoking cessation: The most important modifiable risk factor. Quitting smoking at any age can reduce your risk of AMD progression.
- Sun protection: Wear UV-blocking sunglasses and wide-brimmed hats when outdoors to protect your eyes from harmful radiation.
- Regular exercise: Moderate physical activity supports cardiovascular health, which is linked to eye health.
- Blood pressure management: Maintaining healthy blood pressure reduces the risk of cardiovascular disease and may benefit eye health.
- Weight management: Maintaining a healthy weight reduces the risk of AMD progression and supports overall health.
Regular monitoring and follow-up care
Consistent monitoring is crucial for anyone with wet macular degeneration or at high risk for developing it.
Monitoring schedule
- Active treatment phase: During initial treatment, expect monthly visits to assess treatment response and adjust therapy as needed.
- Maintenance phase: Once stable, visits may be scheduled every 6-12 weeks, depending on your individual response and risk factors.
- Self-monitoring: Daily use of the Amsler grid can help detect changes between appointments. Any new distortions or blind spots should prompt immediate contact with your eye care provider.
What to expect during follow-up visits
- Visual acuity testing: Regular measurement of your vision to track changes over time.
- OCT imaging: Monitoring retinal thickness and fluid levels to assess treatment effectiveness.
- Injection administration: If you’re receiving anti-VEGF therapy, injections will be administered using sterile technique with topical anaesthesia.
- Treatment planning: Your eye care team will adjust your treatment plan based on your response and any changes in your condition.
Maintain your independence with wet AMD management
If you’re experiencing any symptoms of macular degeneration, don’t delay in seeking professional eye care. Early intervention can make the difference between preserving your vision and facing significant vision loss. Remember that with proper treatment and support, many people with wet macular degeneration continue to lead full, active lives.
Stay informed about new developments in treatment, maintain regular follow-up care, and don’t hesitate to seek support when you need it. Your vision is irreplaceable, and the tools to protect it are more advanced than ever before.
Medical disclaimer: This information is for educational purposes only and should not replace professional medical advice. Always consult with qualified eye care professionals for diagnosis and treatment recommendations specific to your individual situation. Treatment options and availability may vary by location and healthcare provider.
