RETINA

AGE-RELATED MACULAR DEGENERATION

The macula is the central part of the retina that is involved in central sharp vision. Age-related macular degeneration is one of the leading causes of irreversible severe visual loss in the Western world in individuals over the age of 60.

The macula is progressively damaged as a result of age-related changes that presents in 2 major forms:

  • Non-Exudative or Dry AMD

This is the more common form. It is a slowly progressive disease which accounts for 90% of cases. Deposits known as drusen may accumulate beneath the retinal layer. There may be progressive thinning of the macula and deterioration of the nerve function.

  • Exudative or Wet AMD

This makes up 10% of cases of AMD and may cause devastating visual loss. In some instances, good vision may be lost within a few days. It results from the development of abnormal leaky vessels or a membrane beneath the retinal layer. These abnormal vessels may bleed or leak fluid, proteins or fats. This can give rise to a separation of the retinal layers and loss of vision. In the late stage, this may lead to scarring over the macula.

 

Symptoms of Age-Related Macular Degeneration

In dry AMD, the patient may experience a gradual progressive loss of central vision. The onset is insidious and patients may not notice it till it reaches a more advanced stage when the central vision becomes blurry or distorted.

In wet AMD, there may be a sudden dramatic loss of vision. There may also be distortion of vision or a shadow over the central vision. The visual loss may be profound.

 

Treatment for Age-Related Macular Degeneration

A thorough eye examination by an eye specialist will be able to confirm the presence of AMD. Fundus fluorescein angiogram may be performed to look at the extent and severity of the disease.

There is no proven treatment for dry AMD. Certain lifestyle modifications such as stopping smoking may help reduce progression of the disease. The use of low vision aids may also help in the visual rehabilitation of patients.

For wet AMD, laser treatment may be performed to seal off the abnormal vessels, and prevent leakage of fluid from these vessels. Argon laser or photodynamic therapy may be used, depending on the nature and location of the abnormal vessels and membrane. Another option will be getting an intravitreal injection whereby the doctor will inject the medication into your eye. These treatments may help to slow down the progression of the disease and prevent further visual loss.