Photodynamic therapy for wet macular degeneration utilizes a low-powered laser in conjunction with a special light-sensitive dye. In a procedure similar to angiography, this special dye is injected into a vein in the arm and allowed to circulate throughout the body.

When the dye circulates through the blood vessels of the eye, it becomes concentrated in the areas of abnormal blood vessel growth (CNV).

Low intensity laser energy targets the CNV where dye has collected. Click here to watch an 800 Kb movie demonstrating photodynamic therapy.

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At this point, low intensity laser energy is applied to the area of choroidal neovascularization. The injected dye specifically absorbs laser energy, so only the blood vessels where the dye is concentrated are destroyed. Unlike conventional laser treatment, the overlying retina is not damaged in this process.

If the neovascularization recurs after photodynamic therapy, it can be treated again with the same process.

Following many studies of its effectiveness, photodynamic therapy was given FDA approval in early 2000. Many retina specialists believe that PDT will significantly change the way wet macular degeneration is managed.