Marshfield Clinic is the only medical facility in northern and central Wisconsin where people can undergo a new treatment for macular degeneration that helps save sight.

Macular degeneration is the leading cause of blindness for people over age 50 living in the Western hemisphere. Until the new therapy was approved in April, there was no effective treatment for many patients with macular degeneration, according to Scott Paulman, M.D., a Marshfield Clinic-Marshfield Center ophthalmologist and retina surgeon.

Dr. Paulman, along with Marshfield Clinic-Marshfield Center Ophthalmologists Deborah Keenum, M.D., and Gary A. Pesicka, M.D., provide outreach services to Marshfield Clinic sites in Eau Claire, Minocqua and Wausau. These physicians provide the new treatment, called photodynamic therapy (PDT), in Marshfield. Marshfield Clinic had participated in a study to determine whether PDT was effective, and because of that participation has the special "cold" laser needed to conduct this treatment.

Dr. Paulman estimates that more than half his patients have macular degeneration, "and this is a major step forward. This treatment is minimally invasive and better than any option we had six months ago."

Although laser surgery has been used to treat one type of macular degeneration, the treatment itself caused a permanent blind spot with loss of vision. Dry macular degeneration affects 90 percent of people because of age. There is no treatment, but there is evidence that wearing sunglasses while outside, eating dark green leafy vegetables and taking a multi-vitamin daily help reduce its effect. Dry macular degeneration causes slow vision loss over years or decades.

About 10 percent of people with wet macular degeneration account for 90 percent of serious vision loss from the disease, Dr. Paulman said. With wet macular degeneration, blood vessels behind the retina bleed and swell. The retina, a thin membrane that transmits light to the brain, becomes bent and uneven, much like a rug with a ball under it. Vision loss with wet macular degeneration occurs quickly and usually is more severe than with the dry version.

In the past, a thermal or "hot" laser was used to treat wet macular degeneration. It slowed the disease, but it also left a permanent blind spot because nearby healthy tissue also was damaged. Dr. Paulman called this the "innocent bystander effect." Unfortunately, macular degeneration usually occurs in the center of the vision field and the resulting blind spot occurred in the same place.

PDT uses a drug that concentrates in the abnormal blood vessels in the back of the eye and a laser technique with a less damaging light level. PDT can help patients retain their vision because healthy tissue is not damaged, Dr. Paulman said. The combination of the new laser technique and the new drug is the key. Individually, neither have any effect.

PDT doubles patients' chances of keeping the sight they have, Dr. Paulman said. This allows patients to continue to live independently, reading and watching television and sometimes driving.

It is important to treat macular degeneration quickly because once the eye is damaged, even the new laser surgery cannot restore vision, Dr. Paulman said.

Treatment is performed on an outpatient basis. After determining the dosage needed, the drug is given through a vein. The patient waits a few minutes and then the laser surgery begins. Because the drug concentrates only in abnormal vessels, other vessels are not damaged. The laser portion of the treatment takes less than two minutes.

Macular degeneration is likely to recur, even with PDT treatment, Dr. Paulman said. Most patients need four to five treatments in the first two years. After that, the need for treatment is reduced.

It is crucial to catch macular degeneration early to avoid permanent damage. Yearly checkups are needed and if patients notice symptoms of macular degeneration between appointments they should call their ophthalmologist immediately, Dr. Paulman said. Symptoms include painless blurriness in the center of vision or distortion of straight lines.