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Capillary Malformations

Capillary Malformations

A capillary malformation (also known as a port-wine stain or port-wine birthmark), is a flat, sharply defined vascular discoloration of the skin. It may cover a large surface area or it may be scattered and appear as smaller spots of color. It can be found be anywhere on the body.

Capillary malformations are a group of abnormal tiny blood vessels of the skin. These vessels form incorrectly before a baby is born. Capillary malformations are not caused by any drug, medication or environmental factor that the baby may have been exposed to during the pregnancy.

A genetic change (mutation) was found in affected skin of capillary malformations, but not present in nearby normal skin. Most capillary malformations are not inherited. When a person has multiple lesions, he or she could have an inherited condition.

Another capillary vascular lesion, nevus simplex, is seen in newborn infants. This is often confused with capillary malformations. When these birthmarks appear on the forehead, eyelids, nose, or upper lip, they are called "angel kisses." When located on the back of the neck, scalp, or back, the lesions are called "stork bites." These lesions fade by 1-2 years of age. They do not require treatment.

What Do Capillary Malformations Look Like?

Capillary malformations look pink, red, or purple due to an increased number and size (diameter) of blood vessels involved in comparison to normal capillaries of the skin. As your child grows, the affected blood vessels may continue to enlarge and thicken. This will cause the color of the lesion to darken. Over time, clusters of tiny, dilated venules (small vessels that collect blood from the capillary junctions and join to form veins) may give a lumpy look to the skin. The degree and length of time to develop skin thickening varies greatly. This may be delayed into early or mid-adulthood.

How are capillary malformations diagnosed?

Most capillary malformations are diagnosed by history and physical exam alone. Sometimes imaging with ultrasonography or magnetic resonance imaging (MRI) is needed to exclude similar or related conditions

What are the possible complications?

Capillary malformations can be connected with overgrowth of underlying soft tissues or bones. The color of a facial lesion can darken. Facial skin may also thicken and form nodules (become “lumpy”) over time. Inflammatory lesions called pyogenic granulomas may develop, which frequently bleed.

When the capillary malformation involves the forehead and / or upper eyelid, abnormalities of the eye and / or brain may occur (Sturge-Weber syndrome). All lesions around the eye should have routine eye exams to evaluate for glaucoma. Magnetic resonance imaging (MRI) may be used to determine if there are any brain changes related to Sturge-Weber syndrome.

Capillary malformations in the skin directly over the spine can be associated with spinal abnormalities. This can include tethering of the spinal cord. These malformations should be investigated with an ultrasound or MRI of the spine.

How are capillary malformations managed?

Several treatment approaches are used to treat capillary malformations.

Laser therapy with the pulsed-dye laser is the standard treatment for capillary malformations on the face. A goal of treatment is to prevent lesions from thickening over time. Another goal is to lighten the capillary malformation. Many lesions lighten significantly after multiple treatments. Very few malformations go away completely. Usually the laser treatment results are better in the facial area than on the trunk or limbs. Deeper vessels do not respond as well as vessels near or on the skin surface. The number of treatments needed depend on the size and depth of the malformation. Treatments are usually done two-three months apart. A topical anesthetic and / or general anesthesia are used because the procedure can be painful. General anesthesia is preferred in children.

Surgical procedures may be considered when there is too much soft tissue or bone enlargement. Surgery and skin grafting may be recommended if the skin is very thick and laser therapy is not successful.

There are no beneficial medication options currently.

What are the risks and side effects of treatment?

There are risks for both laser therapy and surgery. The risks of pulsed-dye laser are low if treatment is performed by an experienced doctor. Rarely, blistering may occur, resulting in scarring. Pigment changes, either whitening or temporary darkening of the skin may also occur. Even with laser treatment, a capillary malformation may return after several years.

The risks of surgery depend upon the type of surgery performed. General risks of surgery include infection, bleeding and scarring. A risk of skin grafting is loss of the graft.

Last Updated 02/2020

Reviewed by Kiersten Ricci, MD

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