Unfortunately, effective treatment for macular degeneration is limited to a small minority of people. However, new methods of treatment are being developed and tested. A wide variety of therapies are being considered, including:

• Low dose radiation therapy

• Submacular surgery

• RPE transplantation

• Macular translocation surgery

• Laser treatment of drusen

• Medications

We will briefly discuss each of these experimental treatments.

• Low Dose Radiation Therapy

It is not yet known if low dose radiation can stop or slow choroidal neovascularization.

Radiation therapy for wet macular degeneration is under investigation in a number of research centers. Because growing blood vessels are sensitive to radiation, it has been suggested that radiation may stop or slow choroidal neovascularization.

The studies conducted so far have not yielded consistent results. Several small studies have demonstrated some beneficial effects of radiation while other trials have shown no benefit.

• Submacular Surgery

In submacular surgery, fine microsurgical instruments are used to remove neovascular vessels from underneath the retina.
Submacular surgery attempts to remove abnormal blood vessels (CNV) and/or blood from under the retina. To begin the surgery, a technique called a vitrectomy is performed. In a vitrectomy, microsurgical instruments are used to remove the vitreous gel from the eye, and replace the gel with a saline solution.
For many surgeries involving the retina, the vitreous gel must first be removed from the eye in a procedure called vitrectomy.

Next, a small incision is made in the retina to gain access to the sub-retinal space. Using fine microsurgical instruments, the surgeon will pull the neovascular vessels out from under the retina and remove them from the eye.

Early results using this technique have been somewhat disappointing. Vision is rarely significantly improved and the blood vessels may grow back.

• RPE Transplantation

New RPE cells are injected under the retina to replace atrophied or diseased RPE tissue.

In many cases of macular degeneration, it appears that the retinal pigment epithelium, or RPE layer, is the first component of the retina to fail. RPE transplantation attempts to replace diseased RPE tissues with healthy RPE cells.

First, a vitrectomy is performed to remove the vitreous gel from the eye. Then, a small incision is made in the retina to gain access to the sub-retinal space. At this point, RPE cells are injected under the retina.

As time passes and the retina heals, it is hoped that these transplanted RPE cells will arrange themselves properly to replace lost or diseased RPE.

This technique is still highly experimental. Although RPE cells can be implanted successfully, the cells may not form the necessary connections with their neighboring cells and tissues. Additionally, rejection of these cells by the body is possible.

• Macular Translocation

In macular translocation, a portion of the retina that includes the macula is elevated and rotated to a new position in the eye.

Macular translocation is an experimental surgical technique. This technique aims to move the macula when it overlies diseased sub-retinal tissues.

First, a vitrectomy is performed to remove the vitreous gel from the eye. Then, a flap of retina is detached from the underlying tissues, and rotated into a new position. The rotated retina is reattached to an area of healthier sub-retinal tissue.

At this time, this experimental technique is associated with a significant risk of serious complications.

• Laser Treatment of Drusen

Low level laser energy has been found to shrink spots of drusen in some people. Studies are being conducted to determine if this procedure might stabilize or improve vision.

Most people with macular degeneration have some drusen, yellow deposits underneath the retina. Some studies have found that low intensity laser treatment causes drusen to shrink and even disappear in some people.

Although this low intensity laser treatment can make the drusen disappear, there is no scientific proof so far that this treatment is beneficial.

• Medications

Dying tissues in the retina may release chemicals (arrows) which stimulate the growth of new, leaky blood vessels.

Some studies suggest that choroidal neovascularization (CNV) is caused by sick and dying tissues in the retina. Many scientists believe that these dying tissues release chemicals, called vasogenic factors, which stimulate the growth of new blood vessels.

Current cancer research suggests that some tumors can be controlled if neovascular growth is inhibited by medication. Similarly, some of these drugs may be able to control the proliferation of blood vessels in wet macular degeneration.

Several medications that block the effects of these vasogenic factors are being tested. By blocking the growth of CNV before it starts, it is hoped that retinal scarring and visual loss may be prevented. Many investigators believe that medications will play a major role in the treatment of macular degeneration in the future.

These experimental treatments are being studied by numerous researchers around the world. It is hoped that one or more of these procedures will lead to more effective treatment of macular degeneration in the near future.