As the eye looks straight ahead, the macula is the point of the retina upon which the light rays meet as they are focused by the cornea and the lens of the eye. Similar to the film in a camera, the retina receives the images that come through the "camera-like" lens. If the macula is damaged, the central part of the images are blocked as if a blurred area had been placed in the centre of the picture. The images around the blurred area may be clearly visible.

Macular Degeneration is damage or breakdown of the macula. The eye still sees objects to the side, since side, or "peripheral" vision is usually not affected. For this reason macular degeneration alone does not result in total blindness. However, it can make reading or close work difficult or impossible without the use of special low vision optical aids.

The retina is the delicate layer of tissue that lines the inside wall of the back of the eye, The macula is a very small area in the centre of the retina. In size, the macula is about the same as a capital "O" in the type of this pamphlet. This small area is responsible for our central "straight ahead" sight used for reading and other fine tasks . Although macular degeneration most often occurs in older people, aging alone does not always result in central visual loss. Nevertheless, macular degeneration is the leading cause of impairment of reading and fine "close-up" vision in Australia.

The most common form of macular degeneration is called involutional macular degeneration. This form accounts for 70 % of cases and is associated with aging. About 10% of macular degeneration falls into a category called exudative macular degeneration. Normally, the macula is protected by a thin tissue that separates it from very fine blood vessels nourishing the back of the eye. Sometimes these blood vessels break or leak and cause scar tissue to form. This often leads to the growth of new abnormal blood vessels in the scar tissue. These newly formed vessels are especially fragile. They rupture easily and may leak. Blood and leaking fluid destroy the macula and cause further scarring. Vision becomes distorted and blurred, and dense scar tissue blocks out central vision to a severe degree.

Other types of macular degeneration are inherited, may occur in juveniles (juvenile macular degeneration) and are not associated with the aging process. Occasionally injury, infection, or inflammation may also damage the delicate tissue of the macula.

If only one eye is affected macular degeneration is hardly noticeable in the beginning stages particularly when the other eye is normal. This condition often involves one eye at a time, so it may be some time before a patient notices visual problems.

Macular degeneration can cause different symptoms in different people. Sometimes only one eye loses vision while the other eye continues to see well for many years. If both eyes are affected, however, reading and close-up work may become extremely difficult. Macular degeneration alone does not cause total blindness. Since side vision is usually unaffected, most people can take care of themselves quite well .

Colour vision may become dim and these other visual symptoms can develop due to macular degeneration.

Many patients do not realise they have a macular problem until blurred vision becomes obvious. Your ophthalmologist can detect early stages of macular degeneration in the early stages. The ophthalmologist examines the macula carefully with an instrument called the ophthalmoscope to see if damage is present.

The examination usually includes a few more tests:

· A grid test in which the patient looks at a test page (similar to graph paper) will be used to check for the extent of sight loss spots.

· A colour vision test will show whether a patient can tell colour differences, and additional tests will help to discover conditions that may be causing the macula to deteriorate .

· Sometimes a fluorescein angiogram is done. The ophthalmologist injects a dye into the patients arm, and then takes photos of the retina and macula. The dye helps to clarify any blood vessel abnormality that might be present.

Macular degeneration can be detected and diagnosed early by an ophthalmologist if periodic eye examinations are part of health care. Early detection is important since people may not realize their vision is impaired. Having your eyes checked is especially appropriate if other family members have a history of retinal problems . For patients with macular degeneration, early diagnosis by an ophthalmologist may prevent further damage or aid the individual in making a visual adjustment with low vision aids .

There is no cure for the most common involutional form of macular degeneration, However, ophthalmologic laser surgery has been used to retard the spread of the less common exudative form, but only if this treatment applied in the very early stages of the condition . In this treatment, a focused intense beam of laser light is used to seal off leaking membranes and destroy new blood vessels. This reduces further loss of vision from progressive scarring of the macula and the surrounding retina.

An ophthalmologist is the medical doctor (MBBS, FRANZCO) who is educated, trained, and licensed to provide total care of the eyes including the diagnosis and treatment of macular degeneration. Total eye care includes performing comprehensive medical eye examinations, prescribing corrective lenses, diagnosing diseases and disorders of the eye and using the appropriate medical and surgical procedures necessary for their treatment. Only an ophthalmologist can provide total eye care.

Low vision optical aids often improve vision for people with macular degeneration. Many different types of magnifying devices are available. Spectacles, hand or stand magnifiers, telescopes and closed circuit television for viewing objects are some of the available resources. Aids are either prescribed by your ophthalmologist or by referral to a low vision specialist or centre. Bright illumination properly directed for reading and close work are often beneficial. Special lamps can also be helpful. Books, newspapers and other items available in large print offer further help.