Lasers for Photodynamic Therapy (PDT)

Description

Photodynamic therapy (PDT) is a new technique to treat tumor after surgery, chemotherapy and radiotherapy. It has the advantages of small trauma, low toxicity, good selectivity and high applicability. The principle is to apply a drug delivery method to give photosensitive drugs and then irradiate the tumor site with a specific wavelength light source at a certain time interval; using the photosensitizing property of photosensitive drugs, the photosensitive drugs selectively gathered in the tumor tissue are activated to produce a series of chemical, physical and biological light reactions to destroy the tumor under the excitation of the light source. The photosensitized drugs in the new generation photodynamic therapy will transfer energy to the surrounding oxygen to generate highly active monomorphic oxygen. The monomorphic oxygen reacts with nearby biomolecules to produce cytotoxicity and thus kill tumor cells.

Light source is one of the necessary factors to ensure the smooth implementation of photodynamic therapy. A good light source should have the following characteristics:

• The wavelength is near the absorption peak of photosensitive drugs.
• The optical power can be adjusted.
• The light source has a certain amount of tissue penetration during use.
• The laser can be connected with optical fiber to ensure more accurate treatment targeting points.