A hemangioma is a benign (noncancerous) tumor made up of blood vessels. There are many types of hemangiomas, and they can occur throughout the body, including in skin, muscle, bone, and internal organs. Most hemangiomas occur on the surface of the skin or just beneath it. Includes Diseases: Capillary hemangioma; Cavernous.

An arteriovenous malformation (AVM) is an abnormal tangle of blood vessels connecting arteries and veins, which disrupts normal blood flow and oxygen circulation. Arteries are responsible for taking oxygen-rich blood from the heart to the brain. Veins carry the oxygen-depleted blood back to the lungs and heart.

Sclerotherapy is the primary form of nonsurgical intervention for venous malformations. Larger lesions usually are treated with 95% ethanol, while cutaneous and smaller lesions are treated with sodium tetradecyl sulfate (1%). Sclerotherapy is often performed by an interventional radiologist under general anesthesia.