Age Related Macular Degeneration (ARMD)
Age related macular degeneration is an eye disease that causes impairment of the central vision by damaging the macula – the part of the eye developed for seeing very fine detail. ARMD is the main cause of irreversible visual impairment in the western world.
Patients with early ARMD often notice that they are unable to recognise peoples faces from a distance, or that words on a page seem distorted.
What causes ARMD?
An accumulation of waste material takes place within the delicate structures of the central retina over a lifetime due to poor re-absorption. This damages the photoreceptors cells in the retina responsible for sending information to the brain and causes distortion and blurring of central vision. Fortunately a person with ARMD will not go completely blind because it is only the central vision that is affected.
There are two types of ARMD: wet and dry... The dry type is the more common form (90% of ARMD), and causes a mild impairment of central vision over months and years.
The wet type is more serious, and can cause a severe reduction of central vision over a relatively short time. The damage caused by the wet type is due to leaky blood vessels developing within the layers of the retina causing distortion and eventually scar tissue.
Occasionally the dry type can become wet. In most cases of wet ARMD only one eye will be affected initially. Often this may go unnoticed by the patient because the remaining ‘good’ eye makes up for the deficient affected eye.
ARMD has been linked to age, smoking, and poor nutrition. There are other types of macular degeneration that affect younger people. In most of these cases there is a family history of premature macular problems.
Diagnosis
Your optometrist assesses the health of the retina during the eye examination. Any changes in the health of the macula will be monitored.
In the case of wet ARMD the patient is often aware that there is a problem. Typical symptoms include blurred or distorted central vision. In some cases things may look an unusual or different shape.
Treatment
In the early cases of wet ARMD treatment known as Photo Dynamic Therapy can be used to seal the leaking blood vessels and help prevent further damage to the retina.
Lucentis is the latest form of treatment available and was approved in 2009 by the National Institute for Health and Clinical Excellence ( NICE ). It requires several injection of Lucentis or Macugen which in many cases helps to prevent the formation of abnormal blood vessel that tend to leak fluid and blood resulting in scaring and damaging the vision.
Unfortunately there is little that can be done to help restore vision once it has been affected by ARMD. However new research with stem cells and gene therapy for wet ARMD and a new type of laser treatment designed to remove waste products from the inner layers of the retina could even help dry ARMD. The outlook is certainly promising for treatment in the future.
Prevention
Recently there has been a lot of interest in the use of vitamin supplements to help prevent the development of ARMD. No guarantees can be made about their effectiveness at this time, however the advice is that any supplement should contain 10% of Lutein.
Eating 5 portions of green leaf vegetables and fruit per day can help prevent ARMD as particular food groups naturally contain Lutein. These include ---- spinach, kale, broccoli, peas, cos lettuce, brussel sprouts, green beans, cabbage, carrots, blueberries, oranges, peaches, melon, bilberries and papayas. Also food that is high in omega 3 and zinc such as oily fish should be a regular part of our diet.
When outside in bright daylight or sunlight it is wise to wear sunglasses with ultra violet light protection and also a wide brimmed hat or baseball cap as this will reduce the amount of UV entering the eye through the pupil. Exposure to UV over a long period can be a contributory factor to AMD.
Anyone suffering with macular disease can gain help and information from the macular disease society by clicking on the link to the Royal National Institute for the Blind www.rnib.org.uk or by visiting www.beAMDaware.co.uk or www.maculardisease.org
What Factors Influence ARMD
ARMD is linked to age, genetic predisposition, smoking, high body mass index, and alcohol, low intake of antioxidants and zinc as well as poor nutrition. There are other types of macular degeneration that affect younger people. These are much less common and in most of these cases there is a family history of premature macular problems.
