LLLT may work in these types of scars through an inhibitory effect on interleukin-6 mRNA levels and the modulating of platelet derived growth factor, transforming growth factor–beta, interleukins, and MMPs, which are associated with abnormal wound healing, the researchers noted.
Burn treatment
LED exposure was shown to provide benefit for the treatment of acute sunburn in a study of 10 patients.
Treatment once or twice daily for 3 days on half of the affected area decreased symptoms of burning, redness, swelling, and peeling compared with the untreated half. Decreased MMP-1 was noted on the treated side through immunofluorescence staining in one patient, and real-time polymerase chain reaction gene expression analysis showed a significant decrease in MMP-1 gene expression at both 4 and 24 hours after the UV injury on the treated side.
In another study, LED treatment was effective compared with control for speeding the healing process of laser treatment–related burns. In nine patients with second-degree burns from nonablative laser devices, LED therapy once daily for 1 week was associated with 50% faster healing based on both patient and physician accounts.
LED treatment also was shown in a pilot study to accelerate re-epithelialization of a forearm injury induced by a CO2 laser; identical test sites were treated with daily dressing changes and polysporin ointment, but the site with faster re-epithelialization had also received the LED treatment (a computer pattern generator was used to deliver the identical CO2 treatment to both sites).
Psoriasis
LLLT also shows promise for the treatment of plaque psoriasis. In a preliminary study, the combined use of sequential NIR (830 nm) and visible red light (630 nm) led to resolution of psoriasis in patients who were resistant to conventional therapy. The patients received treatment in two 20-minute sessions, 48 hours apart, for 4 or 5 weeks. No adverse side effects occurred.
Despite the variety of potential applications for the technology, LLLT remains somewhat controversial due to "uncertainties about the fundamental molecular and cellular mechanisms responsible for transducing signals from the photons incident on the cells to the biological effects that take place in the irradiated tissue" and because "there are significant variations in terms of dosimetry parameter: wavelength, irradiance or power density, pulse structure, coherence, polarization, energy, fluence, irradiation time, contact versus noncontact application, and repetition regimen," the researchers said.
They noted, however, that problems that have been experienced with LLLT – as well as negative study results – could be the result of inappropriate parameters, skin preparation, and/or device maintenance.
"LLLT appears to have a wide range of applications in dermatology, especially in indications where stimulation of healing, reduction of inflammation, reduction of cell death, and skin rejuvenation are required," they noted, but added that the lack of agreement on important parameters (particularly whether red, NIR, or a combination of both is optimal for a given application) has created a credibility gap that must be overcome before LLLT is routinely applied in every dermatologist’s office.
Once LLLT does become so widely accepted, however, it may be time for dermatologists to move on to the next big thing, Dr. Alam said in his article on the future of procedural dermatology.
"For several decades, dermatologists have worked closely with start-up companies to commercialize new devices and technologies ... when new toxins, fillers, and energy devices have been marketed, dermatologists have been early adopters," he said. "Over time, each device or procedure has diminished in cost and exclusivity as other physicians and nonphysicians have entered the market, and dermatologists have moved on to greener pastures. In all likelihood, this cycle will continue," he noted. "Dermatologists cannot prevent the dissemination of stable technologies, but they can continue to innovate and create new ones."
In fact, he added, continued success in this arena will rest largely on clinicians’ ability to nurture innovation to ensure a healthy pipeline of novel technologies.
The authors of the articles had no financial conflicts to disclose.