Laser therapy has been used for a number of years during surgery and to remove small growths and cauterize blood vessels, MedlinePlus states. Cold laser therapy is sometimes called low-level laser therapy. Cold laser therapy, unlike traditional hot laser, doesn't emit heat or burn tissue. Cold laser use is recommended for a number of legitimate medical purposes but is also touted as an unproven cure for a number of other diseases.
Types
Cold lasers are used separately and in conjunction with photosensitizing drugs that activate when light hits them. Use of photosensitizing agents and cold lasers, called photodynamic therapy, is used to treat macular degeneration in the eye as well as some types of cancers. Low-level cold lasers not used with photosensitizers claim to treat a variety of conditions, from tissue damage and pain to high blood pressure and migraines.
Methods
Photodynamic therapy is done by applying a photosensitizing agent directly to the skin or by injecting it through an intravenous needle. Cold laser light of a specific wavelength is aimed at the area requiring treatment for a prescribed amount of time. Low-level laser treatment simply places the laser device over the treatment area and applies low-level wavelengths of different types, depending on the treatment, to the area.
Effects
Cold lasers used in conjunction with photodynamic therapy have proven benefit in reducing tumors or in treating leaking blood vessels in the eye. Low-level laser treatments used without photosensitizing agents have a mixed history in trials for effectiveness, with some studies reporting a benefit for wound healing and reduction in inflammation. Some studies for carpal tunnel syndrome and other musculoskeletal and joint disorders showed pain and functional improvement, the Washington State Board of Labor and Industries reported.
Restrictions
Photodynamic therapy cold lasers can only penetrate as far as light can reach under the skin, the American Cancer Society explains, making them ineffective for deeper treatments. People with allergies to the photosensitizing agents should also not receive the treatment.
Complications
Photodynamic therapy uses light sensitive agents known as photosensitizers, which activate when light hits them. The light reacts with oxygen, causing chemical release that damages cancer cells or abnormal blood vessels. However, since many photosensitizing agents go through the entire body after an intravenous injection, the agent is activated in any area where light of a certain wavelength hits. This includes sunlight. Specific instructions for different types of drugs and treatment must be followed regarding sunlight exposure, or serious tissue damage can occur. Low-level laser treatments cause no such complications but may also provide no benefit, depending on the specific wavelength used and disease being treated.
Considerations
Photodynamic therapy has proven benefit in some medical conditions. Low-level laser therapy has benefit for some conditions and not others. Benefits may depend on the type of wavelength used and the duration of application, which can vary considerably, the American Cancer society reports. Use of low-level laser treatments may also delay the use of more effective medical treatments.
