Infrared lasers preferred for acne, scar treatment

Orlando - Laser and light therapy are becoming viable options for refractive acne and related scarring, says Thomas Rohrer, M.D., who prefers infrared lasers over other available devices.

Recent therapy Only recently have specialists turned to laser and light therapies to treat acne vulgaris. Some lasers and light sources target porphyrins produced by propriobacterium acnes (P. acne). These devices start a chemical reaction that, in turn, destroys the P. acne. Other lasers and light sources focus on decreasing sebaceous gland size and activity. Most of these devices (infrared lasers and radiofrequency devices) also remodel scars and produce new collagen leading to significant improvement in acne scars.

Dr. Rohrer and colleagues have written in a review of the literature on light and laser therapies that is scheduled for publication in an upcoming issue of Seminars in Cutaneous Medicine and Surgery.

Sebaceous glands top priority Non-ablative skin resurfacing lasers with long wavelengths and near or mid-infrared lasers have a two-fold effect.

"I think mostly the studies with infrared lasers being reported now support the fact that they are doing something not only to clear acne, but also to improve the texture of the skin," Dr. Rohrer says.

Several studies have shown the 1450 nm diode laser (SmoothBeam, Candela) to significantly reduce facial acne lesions, from 65 percent to 83 percent, as well as to improve scarring. Treatments range from three to six months at four to six week intervals using 12 - 14 J/cm² with results lasting for months. In one study, five patients required no additional treatment even after six months. Scarring also improved long term. Investigations looking at other infrared lasers (1320 nm and 1540 nm) are producing similarly impressive results. Many of these devices however still require additional large, well-controlled studies, he says.

Those using radiofrequency (RF) to heat the sebaceous gland with a pulse of electromagnetic energy and a cryogen-cooled treatment tip to protect the epidermis (ThermaCool(tm), Thermage) showed promise with 82 percent of patients reporting an excellent lesion response with RF monotherapy in one study. However, the population base was small and follow up-time was limited.

Adverse effects with the non-ablative devices include erythema, edema and pain during treatment. Darker skinned patients may experience transient hyperpigmentation.

Problem with P. acne Irradiating the various porphyrins in P. acne with a pulsed light and heat energy shows both antibacterial and anti-inflammatory effects. However, the shorter wavelengths in many blue, red, yellow and green lasers, ranging from 430 to 1100 nm at half the J/cm² or less than the infrared lasers, require biweekly treatments for successful results.

While these lasers can produce improvement of acne with minimal or no discomfort and few adverse effects, Dr. Rohrer says that "P. acne regenerates rapidly and these treatments must be ongoing to be most effective."

Cost and skill barriers "There is a significant cost associated with these devices and therefore many dermatologists do not have lasers in their own practices and may refer patients to specialty clinics," he says.

While healthcare costs continue to rise, so does the potential for insurance coverage and market competition among manufacturers that may inspire price reductions. But dermatologists need to be prepared to expand their knowledge and expertise to master the art of laser therapy in the best interests of patients who fail traditional oral and topical acne treatments.

Disclosure: Dr. Rohrer performs research on a wide variety of laser and light therapy devices from a number of different manufacturers.