How Common are These Lesions?

Overall, Vascular Anomalies (birthmarks) are seen in well above half of the population.  Simple skin discolorations are very common in newborns and do not require diagnostic testing or treatment.  Infantile Hemangiomas, which usually occur during infancy and gradually disappear in the first few years of life, are also common lesions (benign tumors that are found in ~10% of the infant population). Other types of hemangiomas or tumoral birthmarks such as Rapidly Involuting Congenital Hemangiomas (RICH), non-involuting hemangiomas or intramuscular hemangiomas are less common. Venous malformations (VMs) (or commonly and erroneously called "cavernous hemangiomas") are also common lesions (found in nearly 30-50% of the population), which are usually not symptomatic and therefore do not require treatment. Also, liver hemangiomas and bone hemangiomas are actually venous malformations, and these congenital birthmarks are very common. Small percentage of these patients require treatment due to persistent discomfort and pain.  Port-wine stains (capillary malformations) are also common birthmarks and generally do not require additional diagnostic testing or treatment.  Arteriovenous malformations (AVMs) are not very common lesions, but require intense medical care in most patients.  Other vascular anomalies including lymphatic malformations and combined anomalies (Klippel-Trenaunay syndrome, Parkes-Weber syndrome, Proteus syndrome, Maffucci, etc.) are less common conditions.