PDLs target vascular, pigmented birthmarks

Singapore - Although pulsed-dye lasers remain the most commonly used laser for treating vascular and pigmented birthmarks, they're by no means a perfect or one-size-fits-all solution.

"Laser surgery of birthmarks has been important in the evolution of pediatric dermatology in terms of its procedural and surgical focus," says Lawrence F. Eichenfield, M.D., professor of pediatrics and dermatology, University of California San Diego School of Medicine and chief of pediatric and adolescent dermatology, Children's Hospital, San Diego. "Vascular lasers are still the predominant laser used in pediatrics, mainly for port wine stains, but also for hemangiomas and other vascular lesions."

Like other lasers used by dermatologists, lasers used to treat pediatric patients have evolved from those that provided nonspecific tissue destruction to those that deliver selective, targeted thermal injury.

Neonate treatment

For treating neonates, Dr. Eichenfield recommends beginning treatment at 4 to 6 months of age, allowing a standard set of six to eight treatments within the first year and a half (although this regimen is not evidence-based).

"For large lesions," he adds, "we standardly use general anesthesia. But we have the advantage of pediatrics-specific anesthesiologists in the Children's Hospital setting, which helps to decrease the risk of anesthesia."

Technique

Dr. Eichenfield recommends using a partial-pulse technique. It involves covering a portion of the laser beam with gauze to allow more careful focus on small sections of skin without double-pulsing (Eichenfield LF. Pediatric Derm 1999;16:332-34.). He also advises doctors to wear handle-free metal eye shields when treating port wine stains with pulsed-dye lasers.

Despite a plethora of research into the subject, though, doctors remain uncertain whether treatment at 585 nm delivers significant differences from that at 595 nm.

"Initially," Dr. Eichenfield says, "it was thought that 595 nm was superior to 585 (Geronemus RG et al. Arch Derm 2000;136:942.)."

However, other research suggests 585 nm works better for some patients (Chang CJ et al. Laser Surg Med 2002;31:352-58.).

"This is an area where there's no clear answer. There's probably a variable response depending upon the individual," Dr. Eichenfield says.

For resistant port wine stains, physicians have used treatments including the KTP 532 nm laser, as well as IPL. Both methods, however, appear to achieve only poor to fair success, with a higher incidence of scarring.

For treating pigmented lesions, a wide variety of lasers exists. However, the most successful treatments involve blue-gray lesions such as nevus of ota and other dermal melanocytoses.

"These lesions are more common in Asian patients," Dr. Eichenfield says. "and one of the trends in the literature over the last two years has been extensive series coming out of Asia with shockingly high numbers of lesions being treated with pigmented lesion lasers," he relates.