What is PDT?
PDT stands for Photo-Dynamic Therapy. It is a procedure used to treat the abnormal vessels that grow in the wet form of Age-related macular degeneration (AMD).

The FDA approval of a medication called VisudyneŇ in ocular photodynamic therapy (PDT) for the treatment of wet macular degeneration on April 12, 2000 opened the door for a breakthrough in the efforts to prevent vision loss in wet macular degeneration.

Who is eligible for PDT?
The procedure is mainly used to treat a subset of patients with the wet type of macular degeneration who meet certain criteria set by the studies that evaluated the effectiveness of this procedure. The FDA also approved the use of PDT for abnormal vessels in ocular histoplasmosis and high myopia.

How is the procedure done?
Ocular PDT involves intravenous injection of an inactive medication called VisudyneŇ. This medication is then activated by applying a special type of laser that does not create a burn but rather "turns on" the infused medication. The active form of VisudyneŇ then starts to damage the abnormal vessels growing underneath the retina and prevents them from leaking or bleeding under the center of the retina.

How is PDT different from traditional laser treatment for AMD?
The major breakthrough with this type of procedure is that contrary to the "traditional" laser we had available before, Photodynamic therapy does not close off the abnormal vessels by burning them along with the overlying retina, but rather it destroys the abnormal vascular structure from within leaving the overlying retina virtually unharmed.

How many times do I need to have this procedure done?
In the first year studies have shown that on average Photodynamic therapy (PDT) may need to be repeated (3-5 times) before achieving the desired response.

What special precautions do I need to take after having PDT?
Patient who undergo PDT become temporarily sensitive to light. After having PDT, patients are advised to stay out of direct sunlight or any other intense light directed on their body, like dentist's light for 4-5 days.

What are the side effects of PDT?
Injection site reaction and mild visual disturbance are the more common side effects reported. Low back pain is sometimes reported during the infusion of VisudyneŇ. This usually resolves shortly after the infusion is done.

How can I find out if I am a candidate for PDT?
A formal complete evaluation by a retina specialist should be performed to evaluate the patient's condition and eligibility for PDT. Dr. Safar performs photodynamic therapy at the Jones Eye Institute and the Little Rock VA Hospital. To schedule an appointment please call 501-686-5822 or 1800-942-UAMS or e-mail us at Retina@uams.edu