A laser is a very selective light which is absorbed by the red cells within the hemangioma, creating heat and destruction of blood vessels. Pulsed dye laser is preferentially used, and is quite safe. However, it is not an “eraser” and multiple treatments are typically required to lighten a hemangioma more quickly than expected without treatment. Pulsed dye laser is usually not first line therapy and if used should be combined with other therapies. It only penetrates a millimeter into the skin, and is really of limited benefit in preventing the hemangioma from growing. Pulsed dye laser can be used to improve an infantile hemangioma which is purely superficial, but does not help or prevent a deeper component. There is a small risk of pigmentary change which often resolves with time, and rarely scarring and atrophy. It should be avoided during the rapid growth phase as it does have the potential to cause ulceration. Other drawbacks are that it is moderately painful and costly, and is not always covered by insurance.
Despite these limitations, pulsed dye laser can be beneficial especially when combined with other therapies in certain cases. It is helpful in "mopping up" the small blood vessels that can remain on the surface of the skin after successful treatment with propranolol or timolol or that persist after spontaneous involution. It can also be used to help ulcerated hemangiomas heal more quickly as well as later help any remaining small blood vessels.