Capillary Malformations

What is a capillary malformation?

Capillary malformations are flat, discolored patches on the skin. They happen because of problems with the very small tubes that carry blood (capillaries). The capillaries in a patch of skin stay wide open, which increases blood flow in the area. We do not know what causes this.

Capillary malformations are often called port wine stains because on light skin they look like a splash of purple or dark red (port) wine. On darker skin, the patches may look dark brown or maroon.

They usually follow nerves on the face or arms and legs. A capillary malformation on the eyelid or forehead sometimes is a sign of Sturge-Weber syndrome (SWS), which may affect the  brain.

Capillary Malformations at Seattle Children's

Our Vascular Anomalies Program is nationally known for treating children with vascular disorders. Vascular refers to the tubes (vessels) that carry blood in the body. We are 1 of the largest and most experienced programs in the United States.

We see nearly 2,000 children with vascular anomalies each year, more than any other hospital in the region.

For more information, contact the Vascular Anomalies Program by email or by calling 206-987-4606. If you would like an appointment, ask your child’s primary care provider to refer you.

Providers, see how to refer a patient

  • The experts you need for accurate diagnosis and care
    • We have the skill and experience to correctly diagnose your child’s condition. If tests are needed to confirm it, we have a broad range of imaging studies. Doctors with less experience might confuse a capillary malformation with another type of vascular anomaly, leading to the wrong treatment.
    • Our Vascular Anomalies team brings together experts with many different skills and experiences. These include otolaryngologists, dermatologists, plastic surgeons, general surgeons, ophthalmologists, geneticists and interventional radiologists.
    • Our team helps set national standards for the care of young people with vascular anomalies. We provide the most advanced treatments in our region.
  • Team approach for complete care
    • We schedule visits so your child sees all the specialists they need in as few days as possible. In some cases, we can consult via video phone calls with doctors or patients.
    • Your child’s team will work together – and with you – to make a treatment plan that fits your child’s unique needs. Combining our skills helps make sure your child gets the very best care.
    • As long as needed, our team keeps a watch on your child’s condition. We are always here to answer your questions and connect you to community resources.
  • We treat your whole child
    • Children do not react to illness, injury, pain and medicine in the same way as adults. They need – and deserve – care designed just for them. Our experts focus on how treatments today affect growing bodies in the future. We provide the best and safest treatment for your child, based on our years of experience and the newest research.
    • At Seattle Children's, we work with children and families from around the Northwest and beyond. Whether you live nearby or far away, we can help with financial counseling, schooling, housing, transportation, interpreter services and spiritual care. Read about our services for patients and families.

Symptoms of Capillary Malformations

A capillary malformation begins as a flat, discolored area of skin, caused by increased blood flow.

As your child gets older, the blood vessels in a capillary malformation may become bigger, making the patch darker or thicker.

In adults, the malformations often get bumpy areas. Sometimes, the bumpy areas bleed if they are scratched.

Diagnosing Capillary Malformations

Most often, an experienced doctor can diagnose your child by checking their skin carefully. It is best to see a healthcare provider who is experienced with capillary malformations and other vascular anomalies. The provider can decide if your child needs treatment. This is important because capillary malformations on the upper face can be a sign of blood vessel problems in the brain.

Your child may have imaging studies to confirm the diagnosis and rule out underlying conditions, such as:

Treating Capillary Malformations

Your child’s capillary malformation may not need treatment. We watch for changes and, if needed, recommend laser treatment.

  • Laser treatment

    Laser therapy uses light energy to quickly destroy the extra blood vessels. The most common laser used for capillary malformations is the pulse dye laser. Most patients say the laser feels like a brief sting (like an elastic band snapping against the skin).

    Sometimes, we use a cream to numb your child’s skin first. If the malformation affects a large area, we may need to treat your child while they are completely asleep (under general anesthesia) in the operating room.

    We do laser surgery while your child is awake (outpatient) at our Seattle hospital campus, Bellevue Clinic and Surgery Center and North Clinic in Everett. We do laser treatments that need general anesthesia (inpatient) at our Bellevue center or Seattle hospital campus.

    Most children need several treatments. If the skin becomes thickened and bumpy (nodular), surgery or a different type of laser may improve the appearance. A nodule is a growth under the skin.

Contact Us

If you have questions about a consultation or second opinion, email us or call 206-987-4606. If you would like an appointment, ask your child’s primary care provider to refer you.

Providers, see how to refer a patient

Related Links

Paying for Care

Learn about paying for care at Seattle Children’s, such as insurance coverage, billing and financial assistance.

For Healthcare Professionals