PDD works through a multi-step process: 1. Administration of Photosensitizer: A photosensitizing agent, such as 5-Aminolevulinic Acid (5-ALA), is introduced into the patient's body. This agent is preferentially taken up by cancer cells. 2. Accumulation and Excitation: The photosensitizer accumulates in the cancerous tissues and is then activated by exposure to a specific wavelength of light. 3. Fluorescence Emission: Upon activation, the photosensitizer emits fluorescence, which can be detected using specialized imaging equipment. 4. Visualization and Diagnosis: The emitted fluorescence highlights cancerous tissues, enabling clinicians to differentiate between healthy and malignant areas.
