Age Related Macular Degeneration

Definition

Age-Related Macular Degeneration (AMD) is an eye disease that is the leading cause of vision loss in our senior population. This disease impairs central vision. People who are affected by AMD have problems reading, driving and performing activities that require clear central vision. Currently, there are no treatments for the majority of people who are affected.

Macular degeneration causes damage to the macula of the eye. The macula is a small area at the back of the eye that allows us to see fine details clearly. Macular degeneration makes close work like threading a needle or reading a book difficult or impossible. When the macula doesn't function correctly, we experience blurriness or darkness in the center of our vision. Although macular degeneration reduces vision in the central part of the retina, it does not affect peripheral vision. For example, you could see a clock but not be able to tell what time it is. Macular degeneration alone does not result in total blindness. Most people continue to have some useful vision and are able to live independently.

There are two types of macular degeneration:
The Dry Type. This is the most common form. In this type of macular degeneration, the delicate tissues of the macula become thinned and slowly lose function.

The Wet Type. This is less common, but is typically more damaging. The wet type of macular degeneration is caused by the growth of abnormal blood vessels behind the macula. The abnormal blood vessels tend to haemorrhage or leak, resulting in the formation of scar tissue if left untreated. In some instances, the dry stage of macular degeneration can turn into the wet stage.

Macular degeneration develops differently in each person. Because it will affect regions of the macula differently from person to person, the symptoms tend to vary. Macular degeneration causes a progressive loss of central sight, however, it does not cause total blindness. Peripheral vision is unaffected, allowing a certain amount of mobility in normal surroundings. If left untreated, the wet type of macular degeneration may progress rapidly.

Symptoms

The loss of the ability to see objects clearly
Vision that is noticeably distorted
Straight lines appear wavy
Objects may appear as the wrong shape or size
The loss of clear, correct colors
Difficulty reading
A dark, empty area in the center of vision

The symptoms described above may not necessarily mean that you have age-related macular degeneration. However, if you experience one or more of these symptoms, contact your eye doctor for a complete exam.

Treatment

Currently, there are no treatments for the majority of people who are affected with AMD.
Genetic studies are under way which should enable us to identify those patients at risk. For individuals with macular degeneration, it is recommended that a regular schedule of eye examinations be maintained via an optician or ophthalmologist. During these examinations, detailed documentation with photographs and fluorescein angiography may be performed. With this information, your eye doctor is better able to monitor the condition and note any changes that may occur.

Treatment for Dry Macular Degeneration. There is currently no form of treatment that is known to stop the progression of this type of macular degeneration, although vitamin supplements are often prescribed. Once the retinal tissues are affected, there is little that can be done to stop its slow progression. Nothing has yet been found effective to restore the loss of sight.

Treatment for Wet Macular Degeneration. This form of macular degeneration is controlled in some cases by laser treatments. Laser treatment seals the leaking blood vessels, halting the damage they can inflict upon the retina. These laser treatments are effective in slowing the progress of wet type macular degeneration; however, no treatment has been discovered to restore sight lost to this condition. Research is underway to find new treatments for those that cannot currently be helped by laser therapy.

Photodynamic Therapy.

New treatment for a small percentage (<10%) of patients with a specific type of wet maculopathy where new vessels grown directly beneath the centre point of vision is now becoming available. Treatment involves absorption of laser light by an injected dye. Patients have to fulfil very specific criteria before treatment is considered. These criteria are based on age and on angiographic findings. The ophthalmologist will be able to advise patients on their eligibility but this treatment will only be available in certain centres.

Normal use of your eyes will not cause any further damage.

Patients who have lost vision to AMD should not be afraid

Watch TV or carry out any other usual activity.

Low vision Aids are available to maximise remaining vision.

These are dispensed by a specialist optician and referral
is made by the eye clinic.

Latest treatments

The newest treatment being used for macular degeneration involves use of drugs called anti-vascular endothelial growth factor (anti-VEGF) medications. These drugs help stop new CNV from growing by blocking the effects of a growth factor these blood vessels need to thrive. Anti-VEGF medications are injected directly into your eye. Some anti-VEGF agents that have been approved for use or are currently being investigated for treating macular degeneration include:

Macugen. Pegaptanib (Macugen) is approved for the treatment of wet macular degeneration. This drug is given as a series of injections into the vitreous fluid in the eye. It helps to prevent further vision loss by stopping the formation of new blood vessels and decreasing leakage from existing blood vessels.
Lucentis. Like Macugen, ranibizumab (Lucentis) is an anti-VEGF drug used to treat wet macular degeneration. It also impedes new growth of abnormal blood vessels and helps dry up leaking vessels. However, ranibizumab may be able to reverse some of the effects of macular degeneration, not just prevent further vision loss.

LUCENTIS® (ranibizumab injection) is a prescription medicine for the treatment of patients with wet age-related macular degeneration (AMD).
LUCENTIS is a breakthrough treatment for wet AMD that can do more than just help you maintain your vision. With LUCENTIS, people with wet AMD may see their vision improve or keep the vision they have.
LUCENTIS is an FDA-approved treatment specifically developed for the treatment of wet AMD.
Of patients in key clinical studies taking LUCENTIS monthly...

Up to 40% of patients had a significant improvement of at least 3 more lines (15 letters) on the eye chart
70% of patients could see at least 1 more letter on the eye chart
95% of patients had their eyesight stay the same (lost fewer than 15 letters or 3 lines)
Up to 40% of patients achieved vision of 20/40 or better

And did you know that LUCENTIS...
Was specifically developed for use in the eye, and is FDA approved for the treatment of wet AMD?

Bevacizumab (Avastin). Some doctors are prescribing this drug, which is closely related to ranibizumab, hoping that it will have effects. Bevacizumab hasn't been approved by the Food and Drug Administration (FDA) as a treatment for macular degeneration, but it has been approved as a treatment for colon and rectal cancer. That means that the use of this medication to treat macular degeneration is currently considered an off-label use of the drug. Still, some physicians are using bevacizumab injections to treat wet macular degeneration
Macular translocation surgery. Macular translocation surgery is a treatment that can be used if the abnormal blood vessels are located directly under the fovea. To start the procedure, your surgeon detaches the retina, shifts the fovea away from the CNV and relocates it over healthy tissue. When the CNV is exposed, the surgeon can remove the CNV with tiny forceps or use a hot laser to destroy blood vessels without damaging the fovea. This surgery can be successful for preserving vision, and in some instances improving vision, if your vision loss is recent, the extent of CNV is limited and the tissue around the fovea is healthy. This surgery is not widely used.