How Do Lasers Target and Treat the Skin?
“Laser therapy for skin conditions is actually a scientifically complex procedure,” says Dr. Miriam Hanson, board certified dermatologist and cosmetic expert in Austin, Texas.”In general, the specific wavelength of light produced by the laser targets different chromophores in the skin.”
Chromophores, the color-producing areas of a molecule, interest both scientists and physicians in multiple disciplines, from the treatment of cancer to cosmetic procedures, as they provide an anchor for a laser in the visible light spectrum.
What is a Chromophore?
Simply put, a chromophore is the part of a molecule which gives it its color. In physics, the chromophore of a molecule is the space where the balance of energy between two molecular orbitals falls into the visible light spectrum. This balance of energy in the space is what absorbs certain wavelengths of light and reflects others, resulting in color.
Why is it important for laser therapy?
On the cosmetic side, chromophores are targeted in procedures such as laser hair removal and some other cosmetic skin procedures, like the removal of age spots. Melanin, one of the naturally occurring chromophores in the skin, can be targeted and specifically heated by the laser while leaving the surrounded skin unheated. Heating only the hair follicle and leaving the surrounding skin unaffected, for example, damages the follicle and helps slow or prevent regrowth. A similar process can be used to reduce the appearance for ‘age spots’ – areas of darker pigmentation in the skin that come on with age.
“There are other natural chromophores found in the skin,” says Dr. Hanson. “These include blood and water.” These chromophores are targeted when treating vascular lesions like hemangiomas or rosacea, and skin resurfacing.
Additionally, chromophores have the potential to be useful for the treatment of accessible tumors with non-invasive laser therapy. Research suggests that by exposing specific chromophores to specific wavelengths of light, an accessible tumor can be destroyed through the use of laser therapy.