Vascular Anomalies

Vascular Anomalies Program

Vascular anomalies are abnormal blood vessels or lymphatic vessels. Many are present at birth (congenital) or appear soon after, but some are not noticed until later. Vascular anomalies range from small birthmarks on the skin to large clusters of tangled blood vessels or lymph vessels deep in the body. Sometimes a vascular anomaly is a sign of an underlying condition that affects many parts of the body.

Many vascular malformations are caused by a change in 1 or more genes. This is called a mutation or variant. It can lead to abnormalities in blood and lymphatic vessels in any part of the body. Sometimes the gene changes suddenly before or after birth. Other times, the abnormal gene is passed from a parent to a child (inherited).

“It’s so critical that Seattle Children’s has the technology they used for Emma’s surgery for us to have the great outcome we had.”

– Emma’s mom, Donna West. Read Emma's story.

Why choose Seattle Children’s Vascular Anomalies Program?

Our Vascular Anomalies Program is one of the largest and most experienced programs in the United States. Doctors from across the nation send patients to us for the unique services and expertise we provide.

    • We have treated thousands of children with a wide range of vascular anomalies – from common birthmarks to complex syndromes. We see nearly 2,000 children each year, more than any other hospital in our region.
    • Our Vascular Anomalies team brings together experts from more than a dozen different specialties, with focused expertise in vascular anomalies. These include otolaryngologists, head and neck surgeons, dermatologists, plastic surgeons, ophthalmologists, geneticists, interventional radiologists, orthopedic surgeons, neurosurgeons, neurologists, general surgeons, hematologists-oncologists and pediatricians.
    • • To meet your child’s needs, we work closely with experts in physical therapy, pain management, lymphedema therapy, child life and social work.
    • Our physician-scientists help set national standards for the care of young people with vascular anomalies. We provide the most advanced treatments in our region.
    • A correct diagnosis is the first step toward improving your child's condition. We have the expertise to accurately diagnose your child’s tumor or malformation. If tests are needed to confirm it, we have a broad range of options, such as genetic testing and imaging studies. We counsel families about treatment options and work with you to decide what is best for your child.
    • Our physician-scientists have created a gene panel to test patients’ tissue and body fluids for the genetic changes known to cause vascular anomalies. We can test DNA in tissue sent to us from doctors across the nation. No other children’s hospital has a gene panel certified for clinical use with vascular malformations. This certification means doctors can make treatment decisions based on the results.
    • The gene panel helps us identify the exact genetic cause of a vascular malformation in some children. With such a precise diagnosis, a child’s treatment options may expand to include drugs that target the overactive biological pathway causing the malformation. These targeted therapies may be newly developed or already approved for other diseases.
    • Our genetic testing expertise helps us create new therapies that we offer in research studies called clinical trials.
    • Learn more about vascular anomalies research at Seattle Children’s.
    • 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.
    • Our specialty is treating children’s disease while helping them grow up to be healthy and productive. U.S. News & World Report consistently ranks Seattle Children’s as the top children’s hospital in the Northwest and among the nation’s best.
    • 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 plan your child’s treatment based on years of experience plus the newest research on what works best – and most safely – for children.
    • At Seattle Children's, we work with many 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.

Conditions We Treat

Vascular anomalies

In our Vascular Anomalies program, we see children with many conditions.

Please contact us if you have concerns about any condition, even if it is not listed here.

  • Capillaries are the body's smallest tubes (vessels) that carry blood. Angiokeratomas are wide-open capillaries near the surface of the skin. They can look like fine dark lines and be thicker near the nose.  

  • Arteriovenous (are-TEAR-ee-oh-venus) malformations (AVMs) are tangles of arteries and veins. Their exact cause is unknown, but they seem to develop early in pregnancy. They may look like a swollen, dark spot when your baby is born. AVMs change slowly over time. As your child grows, AVMs can hurt, swell or bleed. They can limit your child's ability to move and may cause other serious health problems. Read more.

  • These flat, discolored marks on the skin have irregular borders. How they look varies depending on a child’s skin color. Most birthmarks slowly clear up by themselves and are gone by the time your child is 18 months old. Those on the back of the neck may stay for years. Other names for birthmarks include macular stains, stork bites, salmon patches or angel kisses.

    Your child should see a healthcare provider who is familiar with birthmarks to make sure the mark is not a capillary malformation, hemangioma or other condition that needs care. Read more.

  • Capillary malformations are flat, discolored patches on your child's skin. They happen because wide-open blood vessels in the patch of skin increase blood flow through the area. They are often called port wine stains because on some skin colors they look like a splash of purple or dark red (port) wine. On darker skin, the patches may look dark brown or maroon. Read more.

  • Curtis marmorata telangiectatica (tel-ANJ-ee-ec-ta-ti-ca) congenita (CMTC) is a rare condition that mainly affects the blood vessels of the skin. At birth or soon after, a fishnet-looking pattern appears on the skin. The blotchy pattern may be widespread or only affect skin on part of the body, such as the legs.

    About half of children with CMTC have other problems. These include:

    • Clusters of extra blood vessels
    • Asymmetry (mismatch of the right and left sides of the body)
    • Pressure in the eye (glaucoma)
    • Delayed development
  • A fibro-adipose vascular anomaly (FAVA) is fatty, fibrous tissue that has grown into a muscle. FAVAs can hurt a lot, causing pain in muscles or nerves. The muscle where the FAVA is located may not work normally. The blood and lymphatic vessels around the FAVA may also be abnormal. A FAVA may be diagnosed at any age, but most often is seen in older children, teens or young adults. 

  • Glomuvenous malformations are made up of abnormal blood vessels and glomus body cells. Glomus bodies help the body regulate temperature by moving blood to or away from the skin surface. They often look like discolored marks or bumps in the skin. Some also involve the underlying muscle or fat. Glomuvenous malformations are often passed from parents to children (inherited). They have been linked to a mutation in the "glomulin" gene.

  • A hemangioma (hee-man-gee-OH-ma) is a cluster of extra blood vessels in or under the skin. Other vascular anomalies are often mistaken for hemangiomas. Hemangiomas often fade over time. Some do not need treatment. Others can cause problems with vision, breathing or feeding. We do not know what causes them.

    A congenital hemangioma is present at birth and grows as a child grows. It is not cancer (benign). There are 2 types: rapidly involuting congenital hemangiomas (RICH) and noninvoluting congenital hemangiomas (NICH).  Involuting means shrinking and fading. RICHs shrink without treatment. NICHs do not shrink. 

    An infantile hemangioma appears within 2 months of birth. It keeps growing for the first few months after it appears and then begins to slowly fade. Our doctors have identified a biomarker to confirm diagnosis of an infantile hemangioma and track if treatment is working. We were among the first in the region to use the medicine propranolol to treat infantile hemangiomas. This has greatly reduced the need for surgery. 

    Read more.

  • Children with hereditary hemorrhagic telangiectasia (HHT), which is an inherited condition, lack the very small tubes (capillaries) that connect an artery and a vein. Without capillaries, blood in an artery flows under high pressure directly into a vein. This can cause the vein to burst and bleed. Seattle Children’s is among the few centers in the United States that can do genetic testing for HHT. We can identify HHT early, test other family members for the condition and advise you about the chance of passing it on in a future pregnancy. Hereditary hemorrhagic telangiectasia is pronounced heh-RED-i-ter-ee hem-or-RAJ-ik teh-lan-jee-ek-TAY-zhuh. Read more.

  • Lymphatic malformations (LMs) affect the tubes (lymphatic vessels) that carry lymph fluid throughout the body. They happen when there is a problem in how these tubes form. As a result, fluids build up in the body's tissues and lymphatic vessels. When the buildup is close to the skin, you can easily see a lump. Most often, LMs are in the head or neck, but they may be anywhere in the body. LMs sometimes erode the underlying bone. This is called Gorham-Stout disease. Read more.

  • Lymphedema happens when the thick body fluid called lymph builds up because of a problem with the lymph vessels or lymph nodes. This causes swelling, most often in your child’s arm or leg. In some children, this happens because the lymph vessels did not form properly before birth. Other times, lymphedema happens because part of the lymph system is removed or damaged. Our certified lymphedema therapists can help ease your child’s swelling. Read more.

  • Pyogenic granulomas are common, harmless growths of blood vessels on the skin. Often we do not know why they happen. They bleed easily, so most often it is best to remove them. Read more (PDF).

  • These rare, noncancerous (benign) tumors are made up of blood vessels. They mostly happen in babies and young children. Kaposiform hemangioendothelioma (KHE) tumors are fast-growing. If the tumor traps and destroys platelets in the blood, it can lead to fatal bleeding. This is called Kasabach-Merritt phenomenon and is mainly treated with steroids and chemotherapy.

  • Venous malformations (VMs) are clusters of extra veins that are full of blood but are not used by the body. VMs are present at birth (congenital), but sometimes cannot be seen until later. Most VMs are painless, dark-colored masses below the skin. They grow slowly as your child grows. As your child gets closer to the pre-teen years, a VM may begin to cause pain and swell. Read more.

Vascular anomaly syndromes

  • Children with blue rubber bleb nevus syndrome (BRBNS) have multiple venous malformations (VMs) on their skin and inside their body, most often related to the bowel.

    The skin VMs appear at birth or in early childhood. They look lumpy, dark and spongy. They may be dark blue, red, purple-red or black in color. Most do not cause problems or harm nearby tissue. Some may be painful or tender to the touch. They rarely bleed unless hit or scratched.

  • Children with this rare disorder may have fatty growths; birthmarks on the skin; and abnormalities affecting the arms, legs, spine, kidneys and blood or lymph vessels. CLOVES is part of a group of syndromes (PROS) caused by changes in the PIK3CA gene. CLOVES stands for:

    • Congenital
    • Lipomatous
    • Overgrowth
    • Vascular malformations
    • Epidermal nevi
    • Scoliosis/skeletal/spinal anomalies
  • Cobb syndrome is a rare disorder that causes clusters of abnormally formed blood vessels in the spine and skin. In the spine, they may be venous malformations or arteriovenous malformations (AVMs). In the skin, the abnormal blood vessels are present at birth (congenital) and may include capillary malformations (port wine stains) or hemangiomas.

  • Klippel-Trénaunay syndrome (KTS) is a rare disorder that is present at birth (congenital). Children with KTS have 1 or more of these signs:

    • A capillary malformation (port wine stain) covering at least 1 arm or leg
    • Swelling or malformation in veins
    • An arm or leg that is larger than the other

    Children with KTS also may have a wide range of other bone and skin problems. Read more.

  • Children with this rare condition have large infantile hemangiomas (clusters of extra blood vessels) on the skin of their lower back and diaper area (perineum). At birth, they may have defects of their urinary tract, genitals, spinal cord, bones, anus or kidneys. LUMBAR stands for:

    • Lower body infantile hemangioma
    • Urogenital defects/ulceration
    • Myelopathy (nerve injury of the spinal cord)
    • Bony deformities
    • Anorectal malformations/arterial anomalies
    • Renal (kidney) anomalies
  • Maffucci's syndrome is a rare genetic disorder. It causes benign (not cancer) overgrowths of cartilage, bone deformities and abnormal blood vessels.

    Most often, blood vessel tumors appear at birth or in early childhood, and may grow over time. Before puberty, children develop nodules on fingers, toes, arms or legs. Children also may have legs of different lengths, side-to-side curve in the spine (scoliosis) and bones that break easily.

  • A child with this condition is born with a large number of abnormal blood vessels. Children have:

    • Capillary malformations: Clusters of small, wide-open blood vessels at the surface of the skin. They usually appear as flat, dark blotches. They are present at birth, although their color may change over time. They usually grow with the child. They are not cancer.
    • AVMs: An AVM happens when the capillaries are missing. Without capillaries, blood flows directly into veins too quickly at high pressure. This can make the blood vessels swell under the skin. They may also burst or bleed.
    • Overgrowth: Abnormal growth of the bones, muscles and tissues in the affected area.
  • PHACE syndrome is a rare disorder that affects different areas of the body. PHACE stands for:

    • Posterior fossa: abnormalities of the brain, especially the cerebellum
    • Hemangioma: a large cluster of extra blood vessels on the face, scalp or neck
    • Arterial lesion: abnormalities of the blood vessels
    • Cardiac defects related to the heart or blood vessels that connect to it, such as narrowing (coarctation) of the aorta
    • Eye abnormalities

    Patients with PHACE may only have some of these problems. How severe it is may vary greatly from child to child.    

  • PIK3CA-related overgrowth spectrum (PROS) is a group of rare overgrowth disorders caused by changes in the PIK3CA gene. These mutations can lead to the overgrowth of various tissues throughout the body, as well as abnormal lymph vessels or blood vessels. CLOVES and Klippel-Trénaunay syndrome are 2 of the more common PROS conditions.

  • This very rare syndrome causes abnormal growth of the bones, skin and head. Symptoms may include:

    • Increased size of a limb, organ or bone
    • Mismatch of right and left limbs (asymmetry)
    • Raised, rough skin
    • Deep lines and overgrowth of soft tissue on the soles of the feet
    • Patches of overgrown blood or lymphatic vessels
    • Local overgrowth of fat (lipomas) or undergrowth of fat
    • Tumors, most often noncancerous (benign)
    • Blood clots deep in the veins (deep venous thromboses or DVT)
  • Children with Sturge-Weber syndrome (SWS) have abnormal blood vessels in their face, brain or both areas. Most children have a birthmark or capillary malformation (port wine stain) on their face at birth. SWS is caused by a change in the GNAQ gene. It is present at birth. Abnormal blood vessels in the brain often cause seizures, vision problems or developmental delays. Read more.

Services We Offer

We offer a wide range of treatments to meet your child’s needs:

  • Many vascular malformations are caused by changes in genes involved in a biological pathway called PI3K/AKT. Our researchers are testing drugs that target this pathway. The goal is to calm down overactive cell growth. Some drugs are newly developed. Others are already approved to treat other conditions. Check our current research studies (clinical trials).

  • Our doctors were the first to use medical-grade Super Glue to make it safer and easier to remove vascular anomalies in a single surgery. This replaces repeated painful injections or multiple surgeries. Guided by real-time imaging, an interventional radiologist places the needle in exactly the right spot. This assures that only the abnormal vessels are injected with glue.

    The glue hardens the malformation without harming the tissue around it. Using a low-dose CT (computed tomography) scan, we make a 3-D image to guide surgeons during the delicate surgery. Surgeons remove the malformation, with glue inside.

    We offer this option to children with malformations in many parts of the body. Read how:

  • We use facial nerve mapping to greatly reduce the risk of nerve injury and scarring when removing vascular malformations in the face. Before surgery, neurophysiologists use small electric pulses to stimulate facial nerve branches and map their exact location. During the procedure, real-time feedback on nerve activity helps guide surgeons. The technique means shorter surgery time, with smaller cuts and near-zero risk of nerve injury.

  • Laser therapy uses light energy to target and destroy extra blood vessels. The type of laser used depends on the type of vascular anomaly. We treat smaller growths in the clinic after using cream to numb your child’s skin. Children with larger lesions often need to be treated in the operating room under general anesthesia. We will talk with you to decide the best choice for your child.

    Outpatient laser surgery is done at our Seattle hospital campus, Bellevue Clinic and Surgery Center and North Clinic in Everett. We do most laser treatments that need general anesthesia at Bellevue Clinic and Surgery Center. Some are done at the Seattle hospital campus.

  • Our certified lymphedema therapists are experienced working with children. They will create a custom treatment plan for your child using complete decongestive therapy (CDT). There are 4 parts to CDT: skin care, gentle massage to improve flow of lymph, compression therapy and exercise. Read more.

  • Seattle Children’s doctors were among the first in the region to use propranolol to treat infantile hemangiomas. This blood pressure medicine is now standard first-line therapy. It can reduce the need for surgery and make needed surgeries less extensive. We study how well this medicine works to shrink tumors and improve how we use it.

    We use other medicines like sirolimus, aspirin and anticlotting drugs to reduce symptoms.

  • Sclerotherapy (SCLAIR-oh-THAIR-uh-pee) blocks unneeded vessels. This treatment can ease pain, reduce the size of a malformation and improve how the skin looks.

    First, an interventional radiologist uses ultrasound guidance to pinpoint the abnormal vessels. Then a doctor injects a solution into the malformation to make it shrink over time. The affected vessel will form scar tissue. Over time, your child’s body will absorb the scar tissue.

    Some children need a series of injections to make their malformation small enough to reduce pain and prevent problems in the affected area. Sometimes the vessel enlarges again, and we need to repeat the procedure. Sometimes sclerotherapy is combined with medicine, embolization or surgery.

    Read more about sclerotherapy (PDF).

  • Your child’s doctors may suggest surgery to remove or reduce the size of a vascular anomaly if:

    • The growth may affect your child’s breathing, eyesight or movement.
    • It causes symptoms such as pain or bleeding.
    • It puts your child at risk of complications like blood clots.

    Surgery may not be an option for some growths because of their size or location. Complete removal may not be possible if the growth is widespread. Some children need multiple surgeries, spread out over a period of time. Your child may have surgery as well as other types of treatment.

Scheduling an Appointment With the Vascular Anomalies Program

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