04 Aug Photodynamic Therapy (PDT) for Macular Degeneration, Obsolete?
Whatever happened to photodynamic therapy? Visudyne®, a form of photodynamic therapy, was one of the first “treatments” for wet, or exudative, macular degeneration and quickly became the treatment of choice. It was approved for the treatment of wet macular degeneration in 2000. The treatment involves infusion of Visudyne® (verteporfin for injection) into the patient, the drug accumulates in the choroidal neovascular complex (the abnormal leaky vessels) and is then exposed to a “cold” laser for 83 seconds. The laser energy converts the accumulated Visudyne® molecules into a drug that seals the abnormal leaky vessels. Vision may improve from absorption of the leaky fluid and blood.
When first introduced, the treatment gained wide acceptance. It was the first treatment that actually gave us (docs and patients) hope of visual improvement. Indeed, it did happen regularly. Treatments are somewhat inconvenient and labor intensive. Patients need to be warned about light sensitivity and sunlight exposure for 5 days after the treatment. Even some surgical lights could theoretically convert the Visudyne® still left in the body. Patients come dressed in hats, gloves and long-sleeves to limit sun exposure. The preparation from our part is somewhat cumbersome, too. It used to take us almost 20 minutes to completely set up for one treatment. The results were exciting. For the first time, patients were getting better vision!
Nowadays, I think most of the patients receive intraocular injections of either Avastin®, Lucentis® or maybe Macugen®. There are still patients that may need PDT/Visudyne. Consider the patients that can not tolerate an intraocular injection, patients with one eye and don’t want the risks of injections and patients that have failed intraocular injections.
Randall V. Wong, M.D.
Ophthalmologist, Retina Specialist