A hemangioma is an abnormal build up of blood vessels in the skin or internal organs.

The classically recognized hemangioma is a visible red skin lesion that may be in the top skin layers (capillary hemangioma), deeper in the skin (cavernous hemangioma), or a mixture of both.

Hemangiomas are usually present at birth, although they may appear within a few months after birth, often beginning at a site that has appeared slightly dusky or differently colored than the surrounding tissue.

Hemangiomas, both deep and superficial, undergo a rapid growth phase in which the volume and size increase rapidly. This phase is followed by a rest phase, in which the hemangioma changes very little, and an involutional phase in which the hemangioma begins to disappear.

During the involutional phase, hemangiomas may disappear completely. Large cavernous hemangiomas distort the skin around them and will ultimately leave visible changes in the skin. A superficial capillary hemangioma may involute completely, leaving no evidence of its past presence.

Hemangiomas may be present anywhere on the body. However, they are most disturbing to parents when they are on the infant's face or head. Hemangiomas of the eyelid may interfere with the development of normal vision and must be treated in the first few months of life. On rare occasions, the size and location of hemangiomas may interfere with breathing, feeding, or other vital functions. These lesions also require early treatment.

Large cavernous hemangiomas may develop secondary infections and ulcerate. Bleeding is common and may be significant following injury to the hemangioma.

• A red to reddish-purple, raised lesion on the skin
• A massive, raised tumor with blood vessels (a possibility)

Hemangiomas are diagnosed by a physical examination. In the case of deep or mixed lesions, a CT scan or MRI scan may be performed to ensure that deeper structures are not involved.

Occasionally, a hemangioma may be associated with other rare syndromes. Additional studies may be done to determine if any of these syndromes are present.