Indocyanine green-augmented diode laser treatment of port wine stains: Clinical and histological evidence for a new treatment option from a randomized controlled trial (RCT)

Complete clearance of port wine stains (PWS) is difficult to achieve, mainly because of the resistance of small blood vessels to laser irradiation. Indocyanine green (ICG)-augmented diode laser treatment (ICG+DL) may overcome this problem.

This pilot study evaluates the feasibility of ICG-augmented diode laser therapy of PWS and compares safety and efficacy of ICG+DL to the flashlamp-pumped pulsed dye laser (FPDL).

In a prospective randomized controlled clinical study, 31 patients with PWS were treated with FPDL (λ_em =585nm, 6J/cm², 0.45ms pulse duration) and ICG+DL (λ_em=810nm, 20–50J/cm², 10–25ms pulse duration, ICG-concentration: 2mg/kg b.w.) in a split-face modus that included histological examination (H&E, CD34). Two blinded investigators and the patients assessed clearance rate and cosmetic appearance.

ICG+DL therapy induced photocoagulation of medium and large blood vessels (>20µm diameter) but not of small blood vessels. According to the investigators' assessment, clearance rates and cosmetic appearance were better after ICG+DL therapy than after FPDL treatment (p=0.114, p=0.291), although not up to a statistically significant level, whereas patients considered these parameters superior (p=0.003, p=0.006).

ICG+DL represents a new and promising treatment modality for PWS, but laser parameters and ICG-concentration need to be further optimized.