ABSTRACT
In 1900, O. Raab's mentor von Tappeiner made the initial observations that led to the evolution of photodynamic therapy (PDT). The principle of PDT relies on the selective accumulation of a photosensitizing drug in diseased tissue with subsequent activation of the drug by illumination of the target tissue with a specific wavelength of light. Based on the finding that vascular damage was a prominent feature after PDT with verteporfin, a series of experiments was designed to evaluate the effect of PDT on normal choroidal vessels in the rabbit eye. Data from early clinical trials of verteporfin PDT for choroidal neovascular membrane (CNV) indicated that CNV reperfused and retreatments would be required. The successful treatment of experimental CNV with verteporfin PDT led to a series of randomized clinical trials which demonstrated a visual benefit of verteporfin PDT for patients with subfoveal CNV.
