Port Wine Stain

This is a multi-center, randomized, double-blind, vehicle-controlled, and sequential group Phase 2 study. Eligible subjects aged 18 to 75 years old with PWB will receive Hemoporfin PDT or vehicle PDT in 8-week cycles at fixed drug dose (5 mg/kg) and different light fluence.

This is a clinical study to evaluate the safety and performance of the Vbeam Pro Laser System for the treatment of vascular indications, including rosacea and port wine stain birthmarks.

The goal of this study is to learn about treatment of port wine birthmarks treated with an FDA-approved 532 nm laser. The main questions it aims to answer are: * How well are the treatments tolerated? * Are there differences in tolerability of the treatment when a single high fluence laser pulse is used (the standard treatment) versus using multiple low fluence pulses? * Are there differences in results when using a single high fluence pulse versus multiple low fluence pulses? type of study: Clinical Trial Participants will undergo 3 monthly laser treatments with the 532 nm DermaV laser. Part of their birthmark will be treated with the standard single-pulse high fluence approach, and other parts will be treated with the multiple-pulse low fluence approach.