What are the treatment options for macular degeneration?

Treatment Options for Macular Degeneration

Anti-VEGF therapy is the most effective treatment for neovascular (wet) AMD, while AREDS2 nutritional supplements are recommended for intermediate dry AMD to slow disease progression and preserve vision.

Understanding Macular Degeneration

Age-related macular degeneration (AMD) is a progressive deterioration of the retina that leads to blurred vision and loss of central vision, primarily affecting adults over 50 years of age. It is classified into two main types:

1. Dry (non-exudative) AMD:

   • More common form (85-90% of cases)
   • Characterized by drusen and atrophy of retinal layers
   • Can progress to geographic atrophy (advanced form)

2. Wet (exudative) AMD:

   • Less common but more severe
   • Characterized by abnormal blood vessel growth in the choroid layer
   • Causes rapid vision loss if untreated

Treatment Algorithm for AMD

For Dry AMD:

1. Early AMD:

   • Regular monitoring
   • Lifestyle modifications:
     • Smoking cessation (strongly recommended) 1
     • Healthy diet rich in green leafy vegetables 2
     • Maintaining healthy body mass index 2
     • Eye protection from sunlight 2

2. Intermediate AMD:

   • AREDS2 nutritional supplements (vitamin C, vitamin E, zinc, copper, lutein, zeaxanthin) 1, 3
   • Self-monitoring with Amsler grid testing 1
   • Regular follow-up examinations (every 6-12 months) 1

3. Advanced Dry AMD (Geographic Atrophy):

   • Multimodal imaging for monitoring (OCT, Fundus Autofluorescence) 2
   • Vision rehabilitation services 1
   • Assistive devices (magnifying lenses, electronic reading aids) 1
   • Implantable Miniature Telescope (IMT) for selected phakic patients with end-stage AMD 1
   • Emerging therapy: Photobiomodulation therapy (under investigation) 4

For Wet AMD:

1. First-line treatment: Anti-VEGF intravitreal injections 1, 5

   • Options include:
     • Aflibercept
     • Ranibizumab
     • Bevacizumab (off-label)
   • Initial treatment at approximately 4-week intervals 1
   • Maintenance regimens:
     • Fixed interval (monthly/bimonthly)
     • Treat-and-extend
     • As-needed (PRN) based on presence of fluid

2. Alternative treatments:

   • Photodynamic therapy with verteporfin 1
   • Laser photocoagulation (rarely used now due to associated blind spots) 1

Evidence-Based Effectiveness

• For Wet AMD: Anti-VEGF therapy has transformed outcomes, with early treatment (within 2 years of diagnosis) significantly reducing legal blindness and visual impairment 1

• For Intermediate Dry AMD: AREDS2 supplements can reduce progression to advanced AMD by up to 36% over a 10-year period 1, 3

• For Geographic Atrophy: Currently limited treatment options, with nutritional supplements providing modest benefit in slowing progression 2, 3

Monitoring and Follow-up

• Patients with unilateral AMD should be monitored closely as the fellow eye is at high risk 1
• OCT imaging is essential for monitoring disease progression and treatment response 1
• Patients should be instructed to report new symptoms promptly (visual loss, metamorphopsia, scotoma) 1

Quality of Life Considerations

• Vision rehabilitation optimizes functional ability for patients with reduced vision 1
• Depression and visual hallucinations (Charles Bonnet syndrome) may accompany severe central vision loss and should be addressed 1
• Special optical or electronic magnifying devices can help with reading and daily activities 1

Important Caveats

• While central visual loss is common with AMD, total visual loss is extremely rare 1
• Smoking is the most significant modifiable risk factor for AMD progression 1
• The informed consent process for bevacizumab should include discussion of its off-label status 1
• Early detection and treatment of wet AMD is critical for better visual outcomes 1