Glossary Term
Photodynamic Therapy (PDT)
Definition
Photodynamic Therapy (PDT) is a medical treatment that uses a combination of light-sensitive drugs (photosensitizers) and light to treat certain types of cancers and other medical conditions. The photosensitizer is administered to the patient and accumulates in targeted tissues. Once the area of interest is exposed to a specific wavelength of light, the photosensitizer becomes activated, producing a form of oxygen that destroys nearby cells. PDT is commonly used for treating superficial cancers, precancerous conditions, and some non-cancerous skin disorders.
Relevance to the MedTech Industry
The aim of PDT is to selectively destroy diseased cells while minimizing damage to surrounding healthy tissues. This non-invasive treatment approach is used in cancer therapy, especially for surface-level tumors, and in the management of conditions such as age-related macular degeneration and acne. PDT offers a targeted treatment option with fewer side effects compared to traditional treatments like surgery or chemotherapy.
Additional Information & Related Terms
Key Components of Photodynamic Therapy (PDT)
Photosensitizer (Drug):
A light-sensitive drug administered to the patient. It selectively accumulates in abnormal or cancerous tissues. When activated by light, the drug generates reactive oxygen species that destroy the targeted cells.
Example: Porfimer sodium (Photofrin) is a commonly used photosensitizer in PDT.
Light Source:
The light source used to activate the photosensitizer is typically a laser or light-emitting diode (LED) that emits light at a specific wavelength, usually in the red or blue spectrum, depending on the photosensitizer used.
Example: A laser is used to deliver light precisely to the area of interest during PDT.
Delivery System (Fiber Optic):
Fiber optic cables are often used to deliver light directly to the targeted area in the body, ensuring that the light reaches deep or difficult-to-access regions, such as tumors or internal organs.
Example: A fiber-optic catheter inserted into the body to direct the light at a tumor in the lung or bladder.
Treatment Protocol:
PDT treatment involves two main phases: first, the photosensitizer is administered to the patient, and second, the targeted tissue is exposed to light. The timing between the administration of the drug and the exposure to light is crucial for maximizing therapeutic outcomes.
Related Terms
Laser Therapy: A form of treatment using focused light, often used in conjunction with PDT to activate photosensitizers.
Photodynamic Diagnosis (PDD): A diagnostic procedure where light is used to detect abnormal tissues or lesions by illuminating photosensitizers already absorbed by these areas.
Laser-Activated Therapy: A type of therapy where lasers are used to activate certain drugs or compounds for targeted treatment.
Reactive Oxygen Species (ROS): Highly reactive molecules generated during PDT when the photosensitizer is exposed to light, leading to cellular damage and destruction of cancerous cells.