• flashlamp-pumped dye laser;
  • fluence;
  • long-pulsed tunable dye laser;
  • port-wine stains;
  • pulse duration;
  • wavelength

Background At present, laser therapy of port-wine stains (PWS) using the flashlamp-pumped dye laser (FPDL) at 450 µs is accepted as the optimal approach. A few years ago, a new long-pulsed tunable dye laser (LPTDL, 1·5 ms) was introduced for the treatment of leg veins.

Objectives To investigate the efficacy and side-effects of FPDL vs. LPTDL therapy of PWS.

Methods Sixty-two patients with untreated PWS underwent test treatments with the FPDL (585 nm; 7-mm spot size; 5·75–7·0 J cm−2 fluence) and LPTDL (585, 590, 595, 600 nm; 5-mm spot size; 11–20 J cm−2 fluence). With the LPTDL, the epidermis was additionally cooled (Spray cooling device). The fading was evaluated clinically 6 weeks after the test treatments.

Results Optimal fading was achieved by the LPTDL (≥ 585 nm) in 30 patients and by the FPDL in 12 patients. No difference was found in 20 patients. At 585 nm, the lasers worked equally well in 12 (FPDL) and 13 (LPTDL) patients, respectively. Results were independent of the localization of the PWS and of the patient's age. In spite of the longer pulse duration, the LPTDL treatment did not result in more side-effects as long as sufficient cooling was provided.

Conclusions The results provide evidence that wavelengths longer than 585 nm can increase the efficacy of treatment in some PWS. Owing to the reduced light absorption by haemoglobin at longer wavelengths and consequently increased depth of the vascular injury, larger vessels can be damaged more adequately using an increased fluence. The LPTDL at 585 nm seemed to be slightly superior to the FPDL, while accepting that due to technical reasons the laser parameters were not directly comparable. Availability of both lasers increases the therapeutic possibilities in PWS.