摘要Objective To obtain an objective assessment of the curative effectiveness of photodynamic therapy (PDT) for port wine stain (PWS), we investigate the relationship between the microvascular perfusion changes of PWS and the blanching of the lesions before and after PDT. Methods Twenty-four patients (18 females and 6 males with a total of 28 lesions) suffering from PWS were treated with PDT. The lesions of various extents were located on the face and neck. After intravenous injection of photosensitizer hepatoporphyrin derivative (HpD), the copper vapor laser was adopted as light source and the lesions of PWS were irradiated. The laser Doppler perfusion imager (LDI) was used to measure the microcirculatory perfusion of PWS before and after PDT and comparison with the normal skin was done.Results All the lesions showed remarkable decrease of tissue perfusion after PDT. It was shown that the mean, maximal and minimal values of tissue perfusion in the pre-treatment group were significantly higher than those in control group (P<0.01). Six months after PDT, the mean, maximal and minimal values of perfusion with the lesions were reduced, with significant difference from pre-treatment group (P<0.01), but no significant difference from control's. The colors of lesions were correlated with decrease of microcirculatory perfusion, which became lightened close to normal skin color without causing any scarring.Conclusions PDT is one of the most effective modalities for PWS. The microcirculation perfusion can reflect the degrees of PWS objectively. The curative effectiveness of PDT for PWS is due to tissue microcirculation response.