ABSTRACT
Photodynamic therapy (PDT) is a therapeutic
modality that entails the administration of a photo-
sensitizer with its subsequent accumulation in the
target tissue and then its activation by non-thermal
monochromatic light corresponding to the sensitizer’s
absorption profile (1). Powerful oxidizing agents such
as cytotoxic singlet oxygen and free radicals are
produced causing irreversible cellular damage. PDT
has traditionally focused on the treatment of cancer
(2), but the potential for selective destruction of
diseased vessels, while sparing normal overlying
tissues, coupled with promising clinical efficacy,
resulted in its use for the treatment of age-related
macular degeneration (AMD), particularly subfoveal
choroidal neovascularization (CNV). PDT selectivity
for the CNV is achieved both through photosensitizer
retention in CNV new vessels and through targeted
light application. Illumination is restricted to the
diseased area and the limited depth of light
penetration restricts damage to underlying tissues.
