Vascular Malformations | The Children's Hospital of Philadelphia

Plastic and Reconstructive Surgery

Vascular Malformations

Capillary vascular malformations (port wine stains)

Capillary vascular malformations look like irregular patches of pink or purple skin that can occur anywhere on the head, body and extremities. They occur in 3 out of every 1,000 births, and the pink color is due to dilated capillary vessels in the dermis layer of the skin.


Commonly called port wine stains, capillary vascular malformations are present at birth and do not go away. They grow proportionately with the child, and although they do not spread out to cover unaffected skin, they can darken and thicken as the vessels slowly dilate when patients reach adulthood.

Capillary vascular malformations that are located on the upper third of the face may also involve the eye and the central nervous system (Sturge-Weber syndrome). Periodic evaluation by an ophthalmologist beginning in infancy is recommended because of the risk of glaucoma. Patients with central nervous system involvement can have seizures, and your pediatrician may order a brain MRI scan to monitor for potential complications.

Capillary vascular malformations may also be accompanied by deeper abnormal vessels such as veins and lymphatics (see Klippel-Trenaunay syndrome), or arteries and veins (see Parkes-Weber syndrome).

Treatment approach

The treatment of choice for capillary vascular malformations is the pulsed yellow dye laser. The laser light is absorbed by the blood inside the vessels, which causes them to heat up rapidly and burst. The treatment causes temporary bruising and then gradual lightening of the pink or purple color. Your doctor will decide whether the treatments can be done in the office using a local anesthetic cream, or if it may be desirable to perform the treatments under a brief general anesthetic in the operating room.

Before undergoing laser treatments, patients should understand that multiple laser treatments are necessary to achieve the best results, and that the laser cannot completely remove the color. The lasers currently available cannot penetrate deeply enough to reach all the vessels; therefore treatment is discontinued once improvement is no longer visible. Different parts of the body may respond differently to the laser. The laser tends to be less effective when used closer to the hands and feet, so laser treatment of the face and neck is generally more successful than that of the extremities.

Laser treatment of head and neck capillary vascular malformations is usually covered by insurance, but treatment elsewhere on the body may not be. We recommend consulting your insurance company to request preauthorization for laser treatment and determine the likelihood of coverage.


Spider angiomas

Spider angiomas are caused by small arteries that travel to the surface of the skin and branch out, resembling a small red spider with tiny legs. Over time, the central feeding artery may dilate, recruiting additional branches and resulting in a slowly enlarging red spot. Spider angiomas can occur anywhere, but they are most noticeable when they appear on the face.  


Pulsed yellow dye laser treatment is usually curative, most often as a single office treatment. Most insurance companies consider this to be a cosmetic condition; consult your insurance company to find out if it covers laser treatment for spider angiomas.


Venous malformations

Venous malformations are dilated veins or abnormal clusters of dilated veins that can occur in utero. In some patients there is a hereditary component, while other patients have no family history of venous malformations. As patients grow, these abnormal veins can slowly dilate, causing visible distortion of the overlying skin as the veins swell with blood. Gravity usually plays a major role in slow enlargement of the veins, and elevation of the involved body part usually results in a decrease in size as the veins empty. Blunt trauma can cause the rupture of these weak dilated vessels, resulting in hematomas.


Patients with venous malformations are particularly susceptible to clots, as the blood flow is very sluggish in the affected veins. Your doctor may request a variety of blood tests (PT, PTT, fibrinogen, and D-dimer) to check the severity of a clotting condition and monitor for potential complications. Patients with localized clots in their abnormal vessels may have prolonged clotting times, measured by protime (PT) and partial thromboplastin time (PTT); reduced amounts of clotting chemicals such as fibrinogen; and increased amounts of a clotting breakdown product known as D-dimer. If your child’s blood test results are abnormal, consultation with hematology is usually recommended.

Treatment approach

Conservative treatment of vascular malformations consists of the use of compression garments. Non-steroidal anti-inflammatory medication can reduce the pain caused by clotted vessels and help to decrease the tendency of the blood to clot.

An MRI scan, and sometimes an MR vein scan, will help to confirm the size and extent of the abnormal veins. Depending upon the type of venous malformation, patients may greatly benefit from sclerotherapy, a technique that most commonly involves injection of sodium sotradecyl sulfate into the veins. This chemical creates a foam that leads to clotting and internal scarring of the veins.

In rare circumstances, a combination of ligation (tying off the abnormal vein where it connects with normal veins) and sclerotherapy is performed. More recently, endovascular laser coagulation (using heat generated by a laser fiber to damage the inside of the abnormal vein) has become available for large, dilated, relatively straight veins.

When the venous malformation includes very superficial veins in the skin or just below the skin, sclerotherapy with a weak alcohol (polidocanol) can be used as another treatment option. Polidocanol is commonly used for cosmetic spider veins and small cosmetic varicose veins in adults.

Surgical debulking of venous malformations may be performed when there is a well-demarcated cluster of dilated veins, or residual soft tissue bulk after sclerotherapy has obliterated the bulk of the abnormal veins.


Arteriovenous malformations


Arteriovenous malformations (AVM) are high-flow vessel abnormalities characterized by dilated arteries that connect directly with draining veins without any capillaries in between. The skin overlying an AVM is usually warmer than the rest of the body, pulsatile, and sometimes even has a detectable vibration (also called a thrill) due to the turbulent high blood flow.

A stethoscope may detect a low rumble (also called a bruit) with each heartbeat. AVMs can cause significant enlargement of the involved area, resulting in soft tissue distortion and bony overgrowth. Growth hormones may result in significant enlargement of the AVM during puberty.

An MRI scan combined with an MRA scan can help to determine the extent and pattern of the abnormal vessels, which impacts possible treatment options. An MRI scan demonstrates the location and extent of an arteriovenous malformation. An MRA scan shows both normal arteries and the abnormal arteries that feed the AVM.

An arteriogram will offer precise anatomic detail as well as a possible opportunity for treatment. In some cases genetic testing is indicated.

Treatment approach

Treatment may consist of the following:

  • Conservative observation. In many cases small or asymptomatic AVMs can be followed without requiring treatment.
  • Palliative or sometimes curative embolization (selective, intentional clotting of the feeding arterial branches combined with injection of the draining veins). This is done with catheters and injection of clotting chemicals or metallic coils by an interventional radiologist. Sometimes blockage of the feeding arteries and the draining veins will cure an AVM. More often, the benefit is temporary, as new arteries will usually begin to feed the AVM
  • Radical surgical removal (sometimes combined with pre-surgical embolization). Surgery aims to cure the AVM by complete removal. These challenging cases may require blood transfusions because of the risk for significant intraoperative bleeding. Intentional blockage of the feeding arteries by interventional radiology is often done the day before surgery to decrease the bleeding risk

Surgical removal with the intention of curing the malformation may warrant complex soft tissue reconstruction. 


Lymphatic malformations

Lymphatics are similar to veins, except they carry water (lymph) instead of blood. They are also part of the immune system. Lymphatic malformations affect only the lymph vessels, and result in water-filled cysts that range in size from microscopic to macrocysts the size of small water balloons.


Veins and lymphatics travel together, and often blood leaks into the dilated lymphatics. This can result in blood blisters and bloody crusts (angiokeratomas) on the surface of the skin which connect to deeper lymphatics below. When the skin blisters and crusts rupture, leakage of bloody lymph may give the appearance of significant bleeding. The drainage is mostly bloody water that doesn’t clot like normal blood, which can be a nuisance for parents and patients.

Lymphatic malformations can also put patients at higher risk for infections. Infections (such as cellulitis) require antibiotic therapy. If oral antibiotics are not sufficient, patients must be admitted to the hospital for intravenous antibiotics.

Lymphatic malformations of the neck region were historically called cystic hygromas. They often contain a combination of micro and macrocysts. When present in newborns, these malformations can cause significant airway problems.

Lymphatic malformations of the lower extremities may be apparent at birth or may not appear until later in life as gravity begins to take effect and water accumulates in the tissues. Puberty may also play a role in the onset of edema. Various names have been given to these lymphatic malformations of the lower extremities, including lymphedema praecox, Meige’s syndrome and Milroy’s disease. A dominant hereditary component may be present due to mutations in genes that control blood vessel growth factors.

Treatment approach

Because lymphatic cysts may drain and shrink spontaneously, conservative observation is a reasonable treatment option when the airway is not involved, but it is not predictable.

Sclerotherapy is the most common treatment for large macrocysts. Therapy may require several consecutive days of injection and catheter drainage combined with intubation to protect the airway. Patients undergoing sclerotherapy for large macrocysts will be monitored in an intensive care unit setting.

Lymphatic malformations comprised of mostly microcysts don’t respond as well to sclerotherapy, and sometimes surgical debulking is useful to decrease the soft tissue fullness. However, lymphatic malformations are associated with repeated bouts of inflammation, which can make dissection difficult. Injury to facial nerves during surgical resection is also a significant concern. Careful nerve monitoring and the use of nerve stimulators to identify important nerves during the operation are used to decrease this risk.

The carbon dioxide laser and a KTP laser are sometimes useful for superficial skin lymphatic cysts and angiokeratomas. The treatments are not curative, but they may result in significant improvement, especially for problematic areas that tend to bleed.

For lymphatic malformations of the lower extremities, surgical treatment tends to be suboptimal, and a lifetime of compression stockings and compression pumps may provide the best long-term results.

Lymph node transfers, which are effective for acquired lymphedema after lymph node dissections for cancer surgery, are not expected to be useful in hereditary lymphedema and congenital lymphatic malformations because of the lack of normal lymphatics.


Pyogenic granulomas (lobular capillary hemangiomas)

Pyogenic granulomas are small clusters of blood vessels covered by a thin, fragile layer of skin. They are thought to be caused by minor skin trauma that stimulates blood vessel growth, and if the skin breaks down (ulcerates), bleeding can be surprisingly profuse. Although these are really a type of hemangioma, and they are actually neither infected (pyogenic) nor granulomas, the name has stuck because of long term use.

Treatment approach

Treatment of pyogenic granulomas may consist of cauterization or pulsed dye laser, but biopsy followed by cauterization or laser coagulation provides a specimen for pathology to confirm the diagnosis. Excision and suture closure is another option. In rare cases, large recurrent pyogenic granulomas may benefit from combination therapy that includes beta blocker therapy directed by CHOP’s Division of Dermatology.




Patients with a condition called tuberous sclerosis may develop small red bumps on their face, especially on the nose and cheeks.

This condition was formerly called adenoma sebaceum because the bumps were thought to be composed of oil glands, but they are actually made of blood vessels and connective tissue. They are now properly called angiofibromas. Although the bumps are benign, they can enlarge slowly and cause significant textural changes to the skin.

Treatment approach

Carbon dioxide (CO2) laser therapy is a very effective way to vaporize these skin lesions. Patients and their parents should understand that the treatment is not curative and it is not possible to make the skin completely smooth. However, improvement may be dramatic, and the laser treatments can be repeated for recurrent angiofibromas.

The pulsed yellow dye laser may help to lighten the reddish pigmentation, but it does not flatten the bumps. For this reason, the CO2 laser treatment tends to be preferred by patients. 



Glomus bodies are a normal part of the skin circulation that help regulate body temperature by constricting blood flow to the skin to preserve body heat, or relaxing to increase skin circulation to release body heat. Abnormal collections of glomus cells, called glomangiomas or glomus cell tumors, are benign clusters of bluish-purple nodules that are often painful and sensitive to pressure.


Glomangiomas are benign but can be annoying, and patients may develop clusters in any part of the body. They may have a dominant inheritance pattern.

Treatment approach

Laser treatment is not usually effective in the treatment of glomangiomas because of the depth of involvement in the skin, and surgical excision is usually recommended for symptomatic lesions. Sclerotherapy may also be of some use, although each blue nodule must be individually injected, which can be tedious and painful.



Hemangiomas are among the most common vascular birthmarks in infants and children. They are the most common benign (non-cancerous) tumor of the skin. Hemangiomas may be present at birth (faint red mark) or appear in the first months after birth. A hemangioma is also known as a port wine stain, strawberry hemangioma and salmon patch.

Children with hemangiomas are treated by a multidisciplinary team including specialists from CHOP’s Divisions of Dermatology, Plastic Surgery, Oculoplastic Surgery and Interventional Radiology. To learn more about the treatment options offered, visit the Infantile Hemangioma Program.



Blood vessel abnormalities may accompany a variety of genetic or inherited syndromes. Patients that present with vascular malformations will receive multidisciplinary care to ensure coordinated treatment for all of their symptoms. Below are examples of some of the combinations and syndromes commonly associated with vascular malformations that we treat through the Divisions of Plastic Surgery and Interventional Radiology, with additional collaboration from Orthopedic Surgery, Hematology and Otolaryngology when indicated.

Venolymphatic malformations

Venolymphatic malformations refer to vascular malformations that affect both veins and lymph vessels. When both veins and lymphatics are abnormal, the malformation may result in lymphatic cysts that contain blood, or varicose and tortuous veins with associated lymphedema. Abnormal dermal lymphatics with associated blood often result in dark purple crusts called angiokeratomas.


As described above, patients may benefit from a combination of laser, sclerotherapy, and surgical debulking. Compression garments are often useful to control reoccurrence after treatment.


Klippel-Trenaunay syndrome 

Patients with Klippel-Trenaunay syndrome, also called Klippel-Trenaunay-Weber syndrome or KT syndrome, commonly have a patchy capillary vascular malformation on the skin surface (port wine stain) as well as an underlying venolymphatic malformation, with hypertrophy of the involved region.


This condition is usually noted at birth, and leg involvement can result in a leg that is longer and larger in circumference than the normal side. There may also be a large lateral varicose vein.

Patients may have involvement that extends up the leg to involve the buttock and retroperitoneum, which can result in rectal or genital bleeding. The trunk and upper extremities can also be involved, and hand involvement can lead to overgrowth of the fingers.

Evaluation & diagnosis
An MRI scan will demonstrate the extent and depth of involvement of the vascular malformation, and it will also confirm the presence or absence of normal draining veins in addition to the dilated varicose veins. This becomes important if patients are candidates for sclerotherapy or endovascular laser coagulation, as they must have a separate normal venous system to maintain circulatory flow from the leg.

Treatment approach
Compression garments are the mainstay of treatment to control progressive dilation of the abnormal veins and lymphatics and progressive swelling and overgrowth of the involved areas, as most patients are not candidates for aggressive debulking surgery. Non-steroidal anti-inflammatory medication may be useful for pain associated with intravascular clotting. Extensive involvement places patients at risk for localized intravascular coagulation and possible pulmonary emboli, and a series of clotting tests (PT, PTT, fibrinogen, d-dimer) may determine whether or not a referral to hematology is warranted to weigh the risks and benefits of systemic anticoagulation.


Parkes-Weber syndrome 

Parkes-Weber syndrome resembles Klippel-Trenaunay syndrome in that it is associated with a combination of abnormal vessels characterized by a patchy capillary vascular malformation (port wine stain) on the surface. Unlike KT syndrome, there is an underlying arteriovenous malformation. This means there is a high blood flow, high blood pressure malformation that may result in more significant overgrowth, a warmer skin temperature, and in severe cases, abnormal bleeding or high output heart failure.


Some cases have a genetic basis and a dominant inheritance pattern. In addition to an MRI and MRA scan, patients may warrant evaluation by our genetics division. Painful AVMs may warrant palliative embolization or surgical excision.


CLOVES syndrome

CLOVES is an abbreviation for a collection of anatomic abnormalities that may include congenital lipomatous overgrowth, vascular malformations, epidermal nevi, and spinal abnormalities. What is most striking are the extensive soft tissue masses of the trunk composed of excess fat and abnormal blood vessels, usually dilated veins and lymphatics. Patients may also exhibit epidermal moles and spinal or skeletal abnormalities. CLOVES syndrome is very rare and the cause is unknown.


Treatment approach
Patients may benefit from sclerotherapy or aggressive debulking. The operations are long and tedious, and blood transfusion is common, but patients may derive significant benefit. In most patients, palliative improvement is the goal rather than complete cure, as these malformations are generally too extensive for complete removal.


Proteus syndrome

Proteus syndrome is a genetic disorder that results in skin and soft tissue overgrowth, abnormal bone development and vascular malformations. Because of the many deformities characterized by asymmetric overgrowth of the extremities and soft tissue masses, the syndrome is named after the Greek god Proteus, who could change his shape. It is believed that the Elephant Man, Joseph Merrick, actually had Proteus syndrome rather than neurofibromatosis. Additional physical characteristics include thickened, wrinkled skin on the soles of the feet and skull abnormalities.


Treatment approach
Because the soft tissue contour abnormalities may be due to excess fatty overgrowth and/or vascular malformations, patients with Proteus syndrome may be candidates for sclerotherapy.

Patients with Proteus syndrome are monitored for possible tumors of the ovaries, testicles, and parotid salivary gland, as well as meningiomas. Evaluation by a hand surgeon is indicated for those with overgrowth of the upper extremity and fingers.


Hereditary hemorrhagic telangiectasia (Osler-Weber-Rendu syndrome)

Also known as Osler-Weber-Rendu syndrome, hereditary hemorrhagic telangiectasia is a dominant hereditary condition characterized by the formation of abnormal vessels on the skin, mucous membranes, brain, lungs, liver and intestines. Significant and repeated episodes of bleeding may require treatment.


When the condition affects the nasal and oral cavity, otolaryngology is usually involved in treatment for endoscopy and cauterization. Cutaneous telangiectasias (spider veins) can respond to pulsed yellow dye laser therapy offered by dermatology or plastic surgery. When the intestines are involved, general surgery may be involved if bowel resection is indicated.

In some cases the interventional radiologist may be called to inject clotting chemicals into feeding vessels to control bleeding, especially in areas that may be challenging to approach surgically.


Blue rubber bleb nevus syndrome

Blue rubber bleb nevus syndrome (BRBNS) is a hereditary form of venous malformations characterized by small clusters of dilated veins that occur predominantly in the skin and gastrointestinal tract. Treatment of problematic cutaneous and subcutaneous dilated veins may include sclerotherapy or direct surgical excision. Significant gastrointestinal bleeding that causes anemia is most effectively treated by bowel resection. 

Reviewed by: David W. Low, MD
March 2013


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