How does photodynamic therapy achieve targeted tissue destruction?

Photodynamic therapy (PDT) effectively achieves targeted tissue destruction through the use of a photosensitizer, which is a light-sensitive compound, in conjunction with laser light. When the photosensitizer is administered to the patient, it selectively accumulates in the targeted tissue.

The next critical step involves exposing the affected area to a specific wavelength of light, typically delivered via laser. This light activation causes the photosensitizer to produce reactive oxygen species (ROS) within the tumor or diseased tissue. The accumulation of these reactive molecules leads to cellular damage, ultimately resulting in tissue destruction while sparing surrounding healthy tissues.

This mechanism is particularly advantageous in treating conditions such as certain cancers, where precision is crucial in minimizing damage to nearby healthy structures. Thus, the combination of the photosensitizer and laser light is what makes photodynamic therapy a targeted and effective treatment modality.