However, the technology does not yet represent a clinical home run, says Ranella J. Hirsch, M.D. Her take home message is, "Stay tuned for more clinical data before making a final judgment." LITTLE DRAMA "There is no question from the in vitro and histological studies that this treatment using low-level illumination has biological effects and induces positive changes," says Dr. Hirsch, vice president of the American Society of Cosmetic Dermatology and Aesthetic Surgery and a private practitioner in Cambridge, Mass. "[However, even if] it is realistic to expect that this noninvasive treatment would result in less dramatic changes than those achieved with more aggressive laser and intense pulsed light photorejuvenation approaches, patient responses to LED have been inconsistent, and clinical improvements quite modest."SHEDDING LIGHT The LED device uses an array of elements to deliver non-coherent light at a wavelength of 590-nm. It induces its effects by modulating the activity of cells in the skin. "This mechanism contrasts with that of lasers and intense pulsed light devices that reverse signs of photoaging, either through ablative effects or by inducing a photothermal reaction. LED treatment involves delivery of very low energy light that results in a biomodulatory effect unrelated to heat generation," Dr. Hirsch explains. REGISTRATION TRIAL The study that resulted in FDA approval of LED treatment was a multicenter trial enrolling 90 patients with a range of skin changes associated with photoaging. They underwent full face treatment twice a week for four weeks and were followed photographically for up to 12 months with serial evaluations. Subsequent studies included computerized optical digital profilometry, and histology using immunofluorescent stains for changes in collagen synthesis and degradation. These in vitro studies showed increases in collagen content in the papillary dermis with evidence of increased collagen I density and a reduction in matrix metalloproteinases that are responsible for collagen degradation. SAFE BUT PROTRACTED "This technique has some advantages in that it is quick, easy and safe for all skin types. However, it does involve a series of eight sessions, it is not inexpensive, and thus is a hard sell to the cosmetic surgery candidate who is seeking noticeable improvement of facial aging. It may have a role for those seeking more modest improvements or maintenance therapy after more aggressive procedures," Dr. Hirsch says. COMING TO LIGHT Meanwhile, clinician-investigators have been exploring additional applications of LED treatment. Their anecdotal reports indicate it may have a role for modulating the immune response to shorten the duration of sunburn and for hastening wound healing. "These reports are intriguing and will be of interest to follow going forward." Dr. Hirsch concludes.
Disclosure Reference Weiss RA, Weiss MA, Geronemus RG, McDaniel DH. A novel non-thermal non-ablative full panel LED photomodulation device for reversal of photoaging: digital microscopic and clinical results in various skin types.J Drugs Dermatol. 2004 Nov-Dec;3(6):605-10. |
