This treatment is occasionally used for patients with wet macular degeneration in which abnormal blood vessels cause fluid to leak beneath the retina. During photodynamic therapy (PDT), a medication called visudyne is injected into the patient's bloodstream and eventually collects within the abnormal blood vessels. A laser is used to activate the visudyne, causing destruction of the abnormal blood vessels without damaging surrounding tissue. This treatment can also be used for patients with central serous chorioretinopathy.
Once treatment has been completed, the patient is advised to wear long-sleeved clothing, a hat, and sunglasses. This type of treatment does cause sunlight sensitivity for up to 5 days.