The Macular is the small area in the centre of the retina at the back of the eye which handles the sharp detailed central part of vision. Surrounded by the peripheral retina, which deals with our surroundings, the macular concentrates the sight on the thing is being looked directly at. The optic nerve is more densely packed in this area, sending a more detailed, clearer image to the brain.
What is Macular Degeneration?:
Macular Degeneration is a gradual, progressive deterioration of the macula. It is painless but unfortunately an incurable disease. It affects older people more than anyone else. Age-related macular degeneration (AMD) is the biggest cause of blindness in the over 60s. It can make performing daily tasks we take for granted, like reading, driving, watching television, recognising faces, safely naviagting around or climbing stairs, very difficult.
Symptoms:
Although it rarely results in total blindness, Macular Degeneration causes "holes" in the individuals central vision and images can be dimmed. It can also caue sensitive to light and loss of colour perception. Anything that needs the detailed central vision becomes gradually more difficult, if not impossible.
Dry (astrophic) Macular Degeneration is the most common type with up to 90% of cases. Initially, white or yellow spots (called Drusen) appear on the macular even before the sight loss is noticed by the sufferer. These can be detected by an ophalmologist and cause inflammation and scaring of the macular and loss of central vision. As yet, there is no known cure for astrophic macular degeneration. About 15% of cases progress into Wet type Macular degerneration.
Wet (neovascular) type effects less than 15% of suffers but causes a faster and more profound loss of sight. Abnormal blood vessels behind the retina grow grow towards the macular. These blood vessels tend to bleed and leak fluid causing damage to the macular by lifting it away from it's base. Though the loss of sight is more rapid in neovascilar macular degeneration there are treatments available.
Causes:
The causes are believed to be a combination of factors. Ones that can't be controlled are age, a predisposed gene (a family history of MD makes it more likely) and it is more common in Caucasians. Lack of exercise, insufficient nutrients in bad dietry habits, high cholesterol, smoking and unprotected exposure to the sun are also thought to contribute to Macular Degeneration.
Links:
- Macular Disease Society
- Macular Degeneration International
- Vision Aware site on Age-Related Macular Degeneration
- RNIB on Macular Degeneration
- NHS page on Maculat Degeneration
More news on macular degeneration on Vision Web Sight:
No comments:
Post a Comment