Background: The conventional pulsed dye laser (PDL), operating at a wavelength of 585 nm and a pulse duration of 0.45 ms, usually does not achieve complete clearance in the majority of port-wine stains (PWSs).
Objective: In this study, we demonstrate the efficacy of a variable-pulse pulsed dye laser (VPPDL) equipped with cryogen spray cooling (CSC) in the treatment of PWS that have become resistant to PDL treatment.
Methods: Forty Asian patients with Fitzpatrick skin types III to IV were enrolled in this study. All patients had previously been treated by the PDL at least eight times (mean, 12.8+/-5.9) and had reached a treatment plateau. A VPPDL with a wavelength of 595 nm and a spot size of 7 mm was used. The patients were treated with fluences between 9 and 15 J/cm(2) and pulse durations of 1.5 to 10 ms. Four treatments were administered at 8-week intervals for each lesion. Three months after the last treatment, all patients were evaluated for the degree of improvement by two independent clinicians.
Results: Eight patients had excellent improvement, 9 had good improvement, 11 had fair improvement, and 12 had poor improvement. No complications were observed during the course of laser treatment. Vessels larger than 30 microm were not seen in the biopsy specimens obtained after the final treatment.
Conclusion: The VPPDL is more effective than the PDL and the VPPDL should be used for treating PDL-resistant PWSs. Nonetheless, vessels less than 30 mum in diameter are resistant to both PDL and VPPDL treatment.