|  Find a Doctor   |   Getting to NUH   |  Appointments   |  Contact Us   |  Newsroom  |  About NUH  |  Make a Gift 

Ophthalmology (Eye) Department

Common Conditions:

Aesthetic Eye-facial Treatment

Dry Eyes

Age-related Macular Degeneration

Floaters

Blepharitis / Meibomitis

Glaucoma

Cataract

Lazy Eyes

Common Eyelid Problems

Myopia

Diabetic Retinopathy

Squints

Home > Patients & Visitors > Diseases & Conditions > Vitreo Retinal Diseases > Age-related Macular Degeneration

Age-related Macular Degeneration

What is Age-related macular degeneration (ARMD)?

Age-related macular degeneration (ARMD) is one of the leading causes of severe, irreversible vision loss in the world. In the west, more than 30% of the elderly population have some form of ARMD. In Singapore, the figure is estimated to be about 27%.

ARMD is an aging change affecting specifically the macula. This can range from deposition of waste material of the eye, loss of retinal cells, or abnormal growth of blood vessels which can result in bleeding and scarring at the macula. Visual loss can vary from mild to severe, depending on the type of degeneration. Unfortunately, this disease has the tendency to affect both eyes.

The most important risk factor for developing ARMD is age. Other possible risk factors include heredity, cigarette smoking, hypertension, high cholesterol levels, long-term unprotected exposure of the eye to sunlight and nutrition. Certain carotenoids (lutein and zeaxanthin) and zinc have been found to lower the risk for ARMD. Lutein and zeaxanthin are found in large quantities in green leafy vegetables such as spinach.

Top

Are there different types of ARMD?

ARMD is generally divided into 2 types:
i) Dry ARMD
ii) Wet ARMD

Dry ARMD:
Dry ARMD is more common than wet ARMD.

In the normal eyes of many people above the age of 60 years, waste material produced by the eye is deposited as yellow specks (called drusen) in the retina. In dry ARMD, drusen deposition is concentrated at the macula and retinal cells in this area undergo degeneration. This results in deteriorating central vision. However, the majority of patients with dry ARMD do not progress to severe visual loss.

Wet ARMD:
Wet ARMD, on the other hand, often results in serious loss of vision. Abnormal blood vessels that grow under the retina can bleed and lead to scarring which ultimately results in severe and permanent visual loss.

Top

What are the symptoms of ARMD?

Patients with early ARMD may have little or no symptom.

In more advanced disease, central vision may deteriorate gradually or suddenly. A blind spot or a patch of blurred vision may appear in the center of the visual field. For example, patient may find letters of a word missing while reading.

Some patients also experience metamorphopsia, which is a term used to describe distortion of images. They may complain that straight edges of objects e.g. doors and floor tiles, look wavy.

These changes in central vision are due to irregularity of the macular surface from drusen, blood or fluid accumulation, loss of retinal cells in the area, and scarring.

Top

How will my eye be examined for ARMD?

The eye will be examined using various lenses and instruments. The pupil will be dilated with eye drops and the eye specialist will examine the retina with some lenses.

In suspicious cases, special tests called fluorescein and indocyanine green angiography may be done to help in diagnosis and planning treatment strategy. A fluorescent dye is injected into a vein in the hand or forearm, and photos of the retina are taken as the dye travels to the retinal blood vessels and lights up abnormal areas.

Top

How can ARMD be treated?

Laser treatment:

Dry ARMD:
There is at present no effective treatment for dry ARMD. Fortunately, severe visual loss is rare.

Wet ARMD:
For wet ARMD, laser therapy is currently the only treatment of proven benefit. It is done for selected cases of ARMD, depending on size and location of the disease. The procedure is painless and done on an outpatient basis under local anaesthesia. The laser is used to destroy the abnormal blood vessels that leak and bleed, and stop them from spreading.

As a separate treatment, laser-absorbing dye may be injected at the time of the treatment to enhance laser therapeutic effects (Photodynamic therapy or PDT). Newer forms of lasers can also treat ARMD without dye by thermal therapy.

Laser treatment for wet ARMD may sometimes improve vision. However, the primary objective of laser treatment is to prevent development of further severe visual loss. In about 50% of patients, the abnormal blood vessels persist or recur after laser treatment, and re-treatments may be necessary. In cases where the abnormal vessels involve the exact center of the macula, laser treatment may cause blind spots in the centre of vision as an expected side-effect.

Are there other treatment options?
Treatment with medication (e.g. interferon and growth factor inhibitors) and radiation therapy are also aimed at destroying the abnormal blood vessels. Unfortunately, none of these have been proven to be effective.

Some cases with large amounts of bleeding may require surgery to remove the blood and abnormal blood vessels. When complemented with eye injections that remove blood clots, the results may be very successful. More recently, macular translocation surgery has been performed to shift the macula to another area unaffected by ARMD. This new surgery, however, is still controversial. Other surgical procedures e.g. retinal pigment epithelial transplantation are experimental.

Top

What if I am not a candidate for treatment?

ARMD does not cause total blindness-- peripheral vision is usually unaffected. For those who suffer from severe and permanent central visual loss, visual rehabilitation using low vision aids like magnifiers and telescopes can improve the quality of life by making the most of residual vision.

Top

Can ARMD be prevented?

There is currently no proven way of preventing ARMD. However, general advice include:

  1. Avoid smoking and alcohol.
  2. Avoid unprotected exposure of the eye to sunlight.
  3. Treat high blood pressure, high cholesterol and obesity.
  4. Increase intake of green leafy vegetables.
  5. Possibly supplementation with zinc, selenium, and vitamin A, C and E may help.
  6. Regular eye examinations should be done to screen for ARMD in those above 60 years of age, especially if risk factors are present.
  7. Those with early ARMD should undergo regular examination. In between examinations, amsler grid (a chart with horizontal and vertical straight lines) monitoring should be done so that any progression causing a change in vision or visual quality may be detected and treated early.
  8. If one eye has already been diagnosed with ARMD, the other eye should be examined regularly and monitored with the amsler grid or graph paper in between examinations as ARMD tends to affect both eyes.

Top


The retina is a sheet of nerve cells lining the back of the eye. It captures images the eye sees, and functions like film in a camera. The retina has to function normally for the eye to see well. Any disease affecting the retina can cause poor vision even if other parts of the eye are normal.

The central region of the retina, the macula, is essential for central and sharp vision. Abnormalities involving the macula may result in inability to see what is straight ahead while peripheral vision remains good.