Cold lasers are handheld devices used by the clinician and are often the size of a flashlight. The laser is placed directly over the injured area for 30 seconds to several minutes, depending on the size of the area being treated and the dose provided by the cold laser unit.
During this time, the non-thermal photons of light that are emitted from the laser pass through the skins layers (the dermis, epidermis, and the subcutaneous tissue or tissue fat under the skin). This light has the ability to penetrate 2 to 5 centimeters below the skin at 90mw and 830 nm.
Once the light energy passes through the layers of skin and reaches the target area, it is absorbed and interacts with the light sensitive elements in the cell. This process can be compared to photosynthesis in plants – sunlight is absorbed by plants, which is then converted to usable energy so that the plant can grow.
When cells absorb this light energy, it initiates a series of events in the cell that is theorized to eventually result in normalizing damaged or injured tissue, a reduction in pain, inflammation, edema and an overall reduction in healing time by increasing intracellular metabolism.