Nevus flammeus

A port-wine stain is a congenital, benign vascular malformation of the skin that appears as a flat, sharply defined, red to purple spot. It is caused by a localized dilation and proliferation of blood vessels in the skin. Around three in 1000 newborns are born with a port-wine stain, with both sexes affected equally often. The port-wine stain is already present at birth and remains for life. In contrast to the harmless stork bite, which usually disappears, a true port-wine stain does not fade by itself. The cause lies in a malformation of the blood vessels during embryonic development. The exact mechanisms are not yet fully understood, but it is not a hereditary disease. The port-wine stain can occur anywhere on the body, but often affects the face and head. The color ranges from light pink to red to dark purple. With increasing age, the color may darken and the surface may thicken slightly. The size varies greatly from small patches to extensive areas that can cover large parts of the face or body. In most cases, port-wine stains are only a cosmetic problem with no health implications. However, a port-wine stain on the face, especially if it affects certain nerve supply areas, can be associated with Sturge-Weber syndrome. This rare condition is associated with vascular malformations in the brain and can lead to epilepsy, developmental delay and glaucoma. Therefore, children with extensive port-wine stains on the face should be thoroughly examined. Diagnosis is made clinically on the basis of the typical appearance. The most effective treatment is laser therapy with a pulsed dye laser. This selectively destroys the dilated blood vessels without damaging the surrounding tissue. Treatment ideally begins in infancy or early childhood, as the skin is then thinner and responds better to the therapy. Several sessions at intervals of a few weeks are necessary. Complete removal is not always possible, but a significant lightening can usually be achieved. Alternatively, the port-wine stain can be covered with special camouflage make-up.