Vascular and pigmented birthmarks.

Vascular and pigmentary lesions compromise most birthmarks. Lesions range from uncommon, to very common, some being essentially normal variants. The natural history of these varies from being transient phenomena of no significance to permanent cutaneous findings that may be associated with significant systemic complications or diseases. This article describes the most frequently encountered clinically important birthmarks, including congenital nevi, hypopigmented lesions, vascular malformations and hemangiomas, discussing clinical presentation, diagnosis, and findings that should prompt early assessment and treatment.