AGE RELATED MACULAR DEGENERATION

AMD is a problem of the macula (the most sensitive part of the retina which is responsible for close work such as reading) and it is related to ageing. Degenerative changes take place in some of the layers of the retina resulting in altered pigmentation, deposition of abnormal material, and deterioration of the function of the macula. This gives rise to disturbance in the central vision ranging from a minor disturbance to complete loss of central vision.
There are two types : Dry- with no fluid collection or haemorrhage and Wet-where there is fluid collection and haemorrhage.
This comes from the abnormal blood vessels that have grown in the deeper layers in the macular area. Macular drusens is a condition that can be a precursor to macular degeneration.

WHO GETS IT?
Normally people over 60 years, but some times even younger. The likelihood of getting it increases with increasing age. Both eyes tend to be affected.

SYMPTOMS?
Difficulty in reading, recognizing faces and close work. Distortion of vision can make straight edges appear crooked. Central blind spot can make details impossible to see. Initially distance vision may be good but it may deteriorate with time so that navigation may become difficult. Occasionally the sight may deteriorate suddenly and may indicate a haemorrhage. The peripheral vision however always remains good providing there is no other coexisting problem. Many patients unfortunately become legally blind.

IS THERE ANY TREATMENT?
In case of dry AMD there is no curative treatment and a specialist optician can help you with low vision aids which will help you read and do some close work. They are basically magnifying aids. Amslar chart is helpful in assessing central vision and may be given to you for monitoring your vision at home in order to be able to pick up small changes early. If picked early in certain situations and in selected patients it may be possible to give laser treatment. Although the vision may be completely lost in some of the area, the progression of the condition can be stopped. A new laser therapy using a special dye has recently become available and may prove to be very beneficial. (photodynamic therapy). Various forms of surgical treatment have been tried, some more successful than others. They include removal of abnormal blood vessels and its membrane from under the macula, and relocation of the macular area so that adjoining healthier retina may be moved to the macular area (macular translocation). These surgeries are not without risks and are undertaken only in specialist centres. If cataract surgery is needed a special type of lens implant can be used instead of the ordinary implant to give better vision.

CAN I DO ANYTHING TO HELP MYSELF?
Vitamins and mineral supplements especially zinc are believed to be helpful in prevention and slowing down deterioration. If you have the wet type of degeneration -  keeping a close watch may be helpful to recognize more serious problems early, and timely laser treatment may prove beneficial. You may not be able to cure it but simple measures such as using a bright light to read and using a magnifier can help in milder conditions.  Smoking should be avoided. Large print books and talking books are available from libraries and some resource centres. If your vision is very poor you may be eligible to be registered partially sighted or blind, this may give you some other assistance and benefits. 

U.S. OK's drug to fight blindness in elderly

(Jul 4, 2006)

The first drug shown to significantly improve the vision of patients threatened by a major cause of blindness in the elderly won U.S. federal approval Friday.

The drug, called Lucentis, treats the wet form of age-related macular degeneration, a disorder where blood vessels behind the retina leak blood and fluid, worsening vision and often causing blindness. An estimated 90 per cent of the 1.4 million Americans who have lost their eyesight due to the disorder have the wet form.

Lucentis, made by Genentech, Inc., a South San Francisco, Calif., biotechnology company, inhibits the growth of blood vessels when injected into the eye. Other Food and Drug Administration-approved treatments can arrest progression of the disease, which can lead to blindness in just weeks or months, but none has been shown to significantly reverse deteriorating vision.

Genentech may find Lucentis competing against another of its drugs, the cancer treatment Avastin.

$17 VERSUS $1,950

Avastin is increasingly used to treat macular degeneration for as little as $17 US a dose. Lucentis will cost $1,950 per injection, or more than 100 times as much. Each drug is typically injected monthly or bimonthly.

Lucentis and Avastin both block the same protein believed responsible for the blood vessel growth. Early results from Lucentis trials led doctors more than two years ago to begin experimenting with Avastin to treat age-related macular degeneration.

"It gave physicians and patients great hope that we are going to be able to improve vision in our patients rather than just slow down the loss of vision,'' Dr. George Williams, a spokesperson at the American Academy of Ophthalmology said of the early results.

Since then, at least 10,000 macular degeneration patients have received Avastin injections, a so-called "off-label'' use of the drug.

"It's become a worldwide phenomenon,'' said Dr. Philip Rosenfeld, a professor of ophthalmology at the Bascom Palmer Eye Institute in Miami, who pioneered its use for age-related macular degeneration.

The Food and Drug Administration does not sanction using Avastin to treat macular degeneration. Genentech stresses that it has not studied the safety or effectiveness of Avastin in treating the disease, nor does it plan to do so.

"We believe Lucentis is a much better choice,'' said Dr. Hal Barron, Genentech's chief medical officer. "I really believe when treating patients, you have to look at the wealth of data supporting its use and the quality of that data.''

Lucentis has not been approved in Canada, a Health Canada spokesperson said, adding it was not known when approval might be given.