Photodynamic therapy (PDT) is a medical treatment that utilizes light activated or photosensitive drugs and a controlled beam of light is administered to the treatment area. Although, PDT is mainly used to treat basal cell carcinoma (BCC), the most common form of skin cancer. It is also used for cosmetic purposes.
The procedure is actually a very basic process. A photosensitizer, which can be in a form of an injectable fluid or a topical cream or lotion, to selectively administer the site of treatment. The drugs are made to affect cancer cells or skin lesions rather than healthy cells. So even though the skin absorbs it, the chemicals would only retain on the affected regions. Although, the time of wait may vary from minutes to hours and even days for the actual photo-treatment.
The device used to ‘activate’ the medicine may also differ depending on the where the site is. If the affected area is on the leg or arm, physicists can opt to use a larger machine.
Otherwise, they use small, hand held devices to selectively administer the light rays. Some PDTs even use small fiber optic lasers to completely focus the site.
The wavelength of the light would also determine how far it would penetrate the human body. And although each drug is activated by receiving a certain frequency of light, they all release an active form of oxygen that ‘burns’ the cells, directly destroying the defective cells and while the body quickly replenishes after a few days. In addition to this, PDT also destroys the blood vessels within the affected area, disabling the nutrients to reach the defective cells while the healthy cells fill in. It may even stimulate the immune system to attack the tumor cells.
However, it does not necessarily mean that the PDT can only cure the skin. In the US, the FDA has also approved this procedure as a invasive way to relieve esophageal and non-small cell lung cancer.
Although, this does not mean that treating internal tissues will be easy. Since light waves can only pass about 1 cm from the skin. Aside from this, PDT is also less effective when treating large tumors because light cannot pass far into these dense form of cells.
But for skin problems that can be easily touched up by this, such as acne, dark spots and other skin lesions due to aging. PDT can be a miracle worker because it has minimal side effects and downtime. Patients can undergo treatment and leave with nothing but a reddish complexion, meaning they can resume their daily activities without any hassles.
However, its popularity may take a toll on since the procedure is only recommended for fair or light skinned people. Darker skinned individuals may experience discolorations or brown patches on site of treatment and since they are also naturally photosensitive, they may also feel slight irritation.