Age-related macular degeneration is defined as changes which occur in the central area of the retina (=macula) in individuals aged over 50 without any obvious cause.
It is the leading cause of blindness in the UK.
Risk factors
- Smoking
- Increasing age
- Family history
- Caucasian
- Previous cataract surgery
2 types:
- Dry
- Characterised by drusen = lipid material in Bruch’s membrane
- Often asymptomatic
- Wet
- Characterised by choroidal neovascularisation – new vessels are fenestrated so allow blood to leak, leading to macular haemorrhage
- worse prognosis
Presentation:
- Dry
- Often detected on routine fundoscopy
- If fovea involved – deterioration of central vision
- Wet
- Central visual blurring, straight lines appear wavy
- Decreased vision
Management:
- Dry and wet:
- Smoking cessation
- Diet
- Diet rich in fruit and vegetables (antioxidant vitamins) and oily fish (omega 3 fatty acids) – not conclusively proven to help but thought to be beneficial
- AREDS formula – very high dose antioxidants (vitamin C, vitamin E, beta-carotene) and zinc
- Beta-carotene is contra-indicated in smokers as increases the risk of lung cancer
- Vitamin E associated with increased risk of heart failure in individuals with diabetes or vascular disease (HOPE study)
- Wet only:
- Intravitreal injection of anti-vascular endothelial growth factor (anti-VEGF) – such as ranibizumab
- Argon laser
- Photosensitising dye (verteporfin) then laser
Small print gem: Patients with visual loss such as macular degeneration may suffer from visual hallucinations. This is known as Charles Bonnet Syndrome.
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