GRAPEVINE, TEX. – The 308-nm excimer laser significantly reduced palmoplantar psoriasis severity in a study of 30 patients.
Multiple studies have demonstrated the efficacy of the excimer laser in the treatment of plaque psoriasis, but few have investigated its use for palmoplantar psoriasis. "Palmoplantar psoriasis is difficult to treat and often recalcitrant to traditional therapies such as corticosteroids. Since the excimer laser can selectively treat psoriatic plaque with higher fluences than is tolerated with traditional phototherapy, it could be a therapeutic modality for the thicker skin on the palms and soles," said Dr. David Goldberg, director of dermatologic laser research at Mount Sinai School of Medicine, New York.
Photo credit: Courtesy Dr. David J. Goldberg
Photo credit: Courtesy Dr. David J. GoldbergModerate palmoplantar psoriasis, shown here, was unresponsive to potent topical steroid therapy.
The 30 patients were aged 18-75 years, with mild to severe psoriasis on their hands and/or feet. All discontinued other treatments 4 weeks prior to starting the study. By study design, patients could receive up to 16 biweekly laser treatments over the course of 3 months with an excimer laser (PHAROS EX-308, RA Medical Systems). Fluences ranged from 400-600 mJ/cm2 depending on disease severity. Short pulses were delivered with a flexible handpiece, with a maximal output of 15 mJ/pulse (J. Cosmet. Laser Ther. 2011;13:47-9).
Each treatment was tailored to the individual patient’s response from the previous session. If there was no response or minimal erythema, the dose was increased by 30%. If there was moderate erythema, the dose was increased by 20%, and if significant erythema, the dose was increased by 10% until the patient could not tolerate further increases. For severe reactions or blistering, the dose was decreased by 20%. The number of sessions ranged from 7 to 14, with a mean of 11.
Palmoplantar psoriasis is shown after the 10th treatment with 308nm excimer laser.
All of the subjects had some improvement by week 5, as measured by the Psoriasis Area and Severity Index (PASI). At the end of the treatments, all showed 50%-100% reductions in scaling, erythema, and flattened plaques. No patient had a relapse detected at the 3-month follow-up, but two-thirds of the patients had relapses by 6 months. There was no evidence of persistent pigmentary changes or scarring. Periodic retreatments will be required, Dr. Goldberg said.
"Although no treatment can be expected to ‘cure’ palmoplantar psoriasis, our data do support the use of the excimer laser to treat patients with hand and foot psoriasis. The excimer laser should be strongly considered for patients with palmoplantar psoriasis unresponsive to other treatments," he concluded.
The excimer laser study was provided on loan by the manufacturer during the course of the study. Dr. Goldberg stated that he had no other disclosures.