Macular degeneration is the name given to certain conditions affecting the retina, which causes loss of central vision. The macula is the small central part of the retina of the eye, which allows detailed vision. Age-related macular degeneration is the leading cause of legal blindness in people over the age of 60.
What is a Macular Hole?
Most macular holes develop in otherwise healthy eyes and are age-related. It also causes impairment of central vision (just like macular degeneration) and people who are very short-sighted are more prone to developing macular holes. Macular holes may also develop following ocular trauma.
What are the symptoms?
It varies greatly and ranges in severity from one person to another. The most common symptoms are blurring of vision with particular difficulty discerning details, both up close and from a distance. It may cause blind spots, resulting in dark or empty areas in the centre of the field of vision. It may also cause distortions of lines and shapes and colour vision may be diminished. Peripheral and night vision usually remains unaffected.
Can AMD be prevented?
At present there is no known way to prevent the occurrence of AMD. There are many promising areas of research that one day may offer preventative therapies for AMD.
Types of AMD:
Dry AMD: This is the more common type of AMD and accounts for 90% of AMD. It usually does not cause total loss of reading vision.
Wet AMD: This accounts for 10% of patients with AMD. When new abnormal blood vessels leak fluid and blood, causing the retinal layer to blister under the macula. At this stage there is marked disturbance of vision in the affected eye.
Is there any treatment for AMD?
There is currently no treatment for the dry type of AMD. various dietary supplements may slow down the progression of the condition.
Macular degeneration surgery has made some breakthroughs with the use of Laser photocoagulation. This can help some people with wet AMD. This treatment cannot restore vision already lost from AMD, so it is critical that it be applied as early as possible, before vision impairment has progressed. Laser photocoagulation is only suitable for a minority of patients and is not appropriate for patients who have blood vessel growth at the centre of the macula.
Photodynamic therapy (PDT) with Avastin or Lucentis injection is a treatment modality that may benefit some cases of wet AMD. PDT reduces the risk of further vision loss, and cannot restore vision already lost. Early treatment leads to better outcomes.