What are the symptoms of ARMD?
Distortion of lines or objects (Alphabets appear distorted or wavy while reading)
Cloudiness or decrease in central vision.Decrease in colour vision
What are the types of Age related Macular Degeneration?
Dry type (drusen)
Most common cause of vision loss in old age, visual loss is usually gradual.
This occurs due to accumulation of a specific material in the ageing cells in the macula as a result of this the cells do not work normally and vision becomes blurred.
Some patients benefit with systemic antioxidant or macronutrient vitamins for the retina.
Wet Type (choroidal Neovascular Membrane)
This occurs in 10-15% of patients with ARMD but the loss of vision is more profound and may also be sudden sometimes.
This occurs due to formation of a membrane or layer of new blood vessels called Choroidal neovascular membrane (CNVM) which occurs beneath the retina. These new blood vessels can leak blood or fluid that leads to loss of vision and distortion.
What are the investigations for ARMD ? FFA and OCT
Can Wet AMD be treated?
- Treatment initiated at the earliest stabilizes the vision.
- Various modes of treatment include:
- Laser photocoagulation
- Photodynamic therapy (PDT)
- Intravitreal injection of Anti-VEGF drugs( Lucentis or Macugen or Avastin)
- Combination therapy or mono therapy will be decided by the retinal specialist.
- Usually a Combination therapy of any two of the above is done
Wet Macular Degeneration
What is Photodynamic therapy?
Photodynamic therapy is performed by injecting a special dye known as Verteporfin. Intravenous verteporfin, selectively localizes in new blood vessels and is activated by laser light on the target area. Non thermal laser energy (diode laser, operating at a wavelength of 689 nm) is then applied locally to the CNVM to produce photochemical reactions that lead to closure of new vessel (thrombosis).
More than one treatment sessions may be required to achieve complete closure.
What are anti VEGF agents?
- Lucentis ( Ranibizumab)
- Avastin (Bevacizumab)
- Macugen (Pegaptanib sodium)
Lucentis /Macugen /Avastin :
These are the latest drugs which have given a ray of hope to improve vision in patient with wet ARMD.These are drugs which prevent the formation of new blood vessels and reduce leakage.
More than one injection may be necessary.