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Q1: Macular degeneration and protection from vitamins. We have a family history of failing sight and my mother suffered from macular degeneration. She was advised to take an eye vitamin rich in lutein and zeaxanthin. I recently saw a different ophthalmologists’, who recommended to me the same vitamins but said I should look for one with Omega 3 fish oils, based upon Areds 2 formulation. With last week's scare what are the pros and cons of taking these vitamins for failing eye health? Philip Williams, Derbyshire.

A1: Age related macular degeneration is the deterioration that occurs with age in the macula. The macula is the most sensitive part of the retina and is responsible for sharp, central vision. The retina is the light sensitive nerve dense layer that lines the back of the eye and transmits the image it receives through the lens to the optic centre in the brain that interprets the visual pattern.

There are two types of age related macular degeneration (ARMD) wet and dry. Dry macular degeneration is fortunately the more common and tends to progress more slowly. It is a simple, atrophic wearing out process of the retina that usually initially only affects one eye, but in time both are likely to be affected. As the retina thins with age related macular degeneration there is increasing distortion of vision and blurring of central vision. Because central vision is progressively lost patients find it increasingly difficult to recognise people because their faces appear blurred and similarly it is hard to read the print on the page of books. Night vision is affected more than day vision.

With dry macular degeneration central vision is eventually lost entirely but the patients don’t become completely blind as they retain peripheral vision. The speed of progress varies and often the progress of the atrophy will be temporarily halted. The initial loss of vision depends on which part of the retina is affected.

Wet macular degeneration is more of a problem. In this condition enlarged abnormal blood vessels develop in the choroid layer of the retina and these extend to involve the highly sensitive macula. In time the macula is raised from its bed and central eyesight is lost. Unfortunately the aberrant blood vessels leak and as they do so the fluid destroys the photo receptor nerve cells. Wet macular degeneration may develop in retinas previously affected by dry AMD. As well as loss of central vision patients with wet AMD notice greater distortion than those with dry AMD and they will also be aware that colours no longer seem to be as bright as they were. Night vision is badly affected.

To return to your specific question about what sort of vitamins should you be taking. The old advice used to be that patients should be encouraged to take as much fresh fruit and vegetables as possible. It was later recommended that they should have a good comprehensive multi vitamin tablet that included trace elements and essential minerals daily as well as a healthy diet. Recently experimental work by the US National Eye Institute have shown that not all vitamin supplements were equally effective in helping to preserve eye health in those who were likely to be susceptible to age related changes. It was found that higher doses of some vitamins than of others was necessary to achieve an advantage, and these had to be taken at a greater concentration, but not in mega doses, than is usually recommended. One firm, Bausch and Lomb has made a speciality of producing vitamins for those who might have a susceptibility to eye problems. One of their preparations has substituted lutein as a replacement for beta carotene, this might be a wise precaution if the patient is also a smoker. Lutein has the advantage that it helps to filter out blue light.

I would, and do, recommend my patients to take Bausch and Lomb’s PreserVision tablets, but if they smoke I suggest that they use PreserVision Lutein. I always recommend patients should take Omega 3. The scare about vitamins, which wasn’t a very big scare and may have been unjustified, didn’t apply to people taking standard multivitamins or even multivitamins in the modified strength that is found in Bausch and Lomb’s preparations.

Q2: My mother is in her eighties and has worn glasses for reading and close work since she was in her thirties. Her eyesight has greadually deteriorated but she now has trouble seeing clearly in anything but the brightest daylight when out of doors. Is there anything that can be done to help an elderly person with deteriorating eyesight? J Green, Nuneaton.

A2: The first essential step is to make a diagnosis. There are many different causes of failing eyesight in old age groups but which particular problem is causing visual changes must be carefully investigated. I am not quite as old as your mother but even so I have my eyes tested every year. I have the pressures within the eyes measured and the optometrist also takes a photograph of the back of the eyes so that each year’s finding can be compared with that of the next year.

A high proportion (over 45 per cent) of people over the age of 75 have some evidence of cataract formation. Many will also have evidence of early dry age related macular degeneration. Both these conditions cause failing vision at all times and with both troubles it is worse when the light is dim so that night blindness becomes a problem.