MODEL RELEASED. Acne rosacea treatment. Face of a woman after having tunable dye laser treatment for acne rosacea. Acne rosacea is a chronic skin disease that occurs in adults. It causes the blood vessels of the face to enlarge, resulting in flushing. It also causes rashes and pustules. Tunable dye laser treatment targets the blood vessels. A microsecond laser pulse is aimed at a blood vessel. The laser heats the blood vessel, which collapses and is reabsorbed by the body. The use of a pulse prevents heat diffusing to other tissues and so targets only the affected blood vessels. The swelling and inflammation recedes after a few days.