Wet and dry AMD represent two distinct forms of the same eye condition affecting the macula, the retina’s central portion responsible for sharp, central vision. These two variants differ substantially in their symptoms, progression, and treatment approaches, making it essential to understand their unique characteristics.
Two faces of the same condition
Dry AMD accounts for approximately 85-90% of all AMD cases and develops when light-sensitive cells in the macula gradually break down. This form typically begins with accumulated drusen, yellow deposits beneath the retina that slowly impair vision over time—most patients with dry AMD experience gradual vision changes that progress over years or even decades.
Wet AMD, in contrast, occurs when abnormal blood vessels grow beneath the retina while leaking fluid and blood. This leakage causes damage to the macula, resulting in more sudden and severe vision loss. Though wet AMD represents only 10-15% of total cases, it’s responsible for approximately 90% of severe vision loss associated with the condition.
While both affect the same eye area, their underlying mechanisms and management strategies differ significantly.
Symptoms that reveal the difference
- Distorted central vision, with straight lines appearing wavy (particularly indicative of wet AMD)
- Blurry areas or blank spots in central vision
- Diminished colour perception and intensity
- Difficulty reading, recognising faces, or performing detail-oriented tasks
- Increased need for brighter lighting
- Vision changes in one or both eyes (often asymmetrical initially)
The onset and progression of these symptoms vary between the two forms. Dry AMD typically develops slowly, with gradual vision changes that may go unnoticed initially. Wet AMD, however, often produces more dramatic symptoms that appear suddenly, sometimes over days or weeks. Any rapid change in vision warrants immediate medical attention, as prompt intervention for wet AMD can help preserve vision.
Diagnostic differences
Eye care specialists use several techniques to distinguish between wet and dry AMD. The examination typically begins with visual acuity testing and dilated eye examination to assess the macula directly. Drusen without fluid indicates dry AMD, while fluid accumulation suggests wet AMD. Advanced imaging technologies provide more definitive differentiation. Optical coherence tomography (OCT) creates detailed cross-sectional images of the retina, revealing drusen in dry AMD or fluid accumulation in wet AMD. For suspected wet AMD, fluorescein angiography helps identify abnormal blood vessels and leakage patterns by tracking dye as it flows through retinal blood vessels.
These diagnostic approaches distinguish between AMD types and help monitor disease progression and treatment response. Regular monitoring is essential for both forms, as approximately 10-15% of dry AMD cases eventually convert to the wet form, requiring prompt changes in treatment strategy.
Treatment strategies
The management of Age Related Macular Degeneration varies significantly between the two forms. For dry AMD, no FDA-approved treatments currently reverse the condition. However, the Age-Related Eye Disease Studies (AREDS and AREDS2) demonstrated that specific nutritional supplements can slow progression in intermediate to advanced cases. These formulations typically contain vitamins C and E, zinc, copper, lutein, and zeaxanthin.
- Nutritional supplements based on the AREDS2 formula
- Mediterranean diet rich in fish, nuts, fruits, and vegetables
- Smoking cessation (smoking doubles AMD risk)
- Blood pressure management and regular exercise
- Protection from excessive UV light exposure
Regardless of type, regular monitoring, immediate attention to new symptoms, and adherence to treatment recommendations remain essential components of effective AMD management.
