Macular degeneration is now recognized as one of the leading cause of blindness, surpassing the combined number of people affected by cataracts and glaucoma.
First, an overview regarding macular degeneration. The eye contains photoreceptor cells at the back of the eye which captures light energy. They cells convert light energy into nerve impulses which travels via the optic nerve to the occipital lobe of the brain for interpretation. Just like a camera, the eye has lens which help to focus the light rays into a central area, known as the macula. When this area deteriorates, some of the photoreceptor cells die, resulting in disturbed visual reception. Depending on the severity of the macular degeneration, the degree of visual disturbance varies accordingly.
When macular degeneration is at an early stage, there may not be significant visual disturbance. This often go unnoticed, allowing the disease to progressively worsen. In the intermediate stage, straight lines may be perceived as being wavy or curved, associated with blurring of vision. In late cases, there is permanent loss of central vision.
To date, there is no definitive cure which is able to completely treat this condition. Once diagnosed, ophthalmologist can only prescribe measures to slow the degeneration or even stop its progression. Lost vision cannot be recovered again.
This is the reason why an immediate visit to the ophthalmologist is necessary should there be symptoms such as straight lines appearing as curved, blurring of vision or reduced central vision. An early intervention is most ideal to manage this condition as it has a much higher chance to slow the progression or even halt the degeneration.
How is macular degeneration detected by ophthalmologist?
The ophthalmologist will do a screening test for macular degeneration, known as the Amsler Grid. It is similar to graph paper where there are a series of straight lines intersecting each other at right angles forming small squares and a thick dot in the middle. By focusing on that dot, a patient with macular degeneration would notice the straight lines as wavy, curved or even broken.
If an abnormality is detected, the ophthalmologist will offer to do diagnostic tests such as fluorescein angiography where a colored dye is used to visualize the abnormal blood vessels in the retina and/or the non-invasive optical coherence tomography which takes cross-sectional images of the retina to look for structural abnormalities at the cellular level.
Everyone is exposed to the risk of macular degeneration. However, this do not mean that everyone will eventually have this condition. The risk can be reduced significantly by lifestyle modification alone. For example, smoking has been linked to increase the risk by two-folds. Hence, smoking cessation offers the greatest risk reduction. Regular exercise as well as protecting the eyes from ultraviolet ray exposure helps to further reduce the risk. When non-modifiable risk factors are present such as advancing age and family member diagnosed with the condition, frequent monitoring is of utmost importance to be able to catch the disease in the early stage.