Vascular malformation has received large attention in the recent years as it was found that the new-born are having this very frequently. So, the clinical features are studied along-with the other pathological subtypes to manipulate the root cause of the disease that seems ordinary but have a great impact on the bodies.
Low magnification micrograph of an arteriovenous malformation in the brain

Image: “Low magnification micrograph of an arteriovenous malformation in the brain” by Nephron. License: CC BY-SA 3.0

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Abnormalities occurring in children and adults are referred to as vascular malformations. Abnormal development of lymph vessels, blood vessels, arteries and veins leads to disturbance within the normal function of that particular area of body through inflammation, pain or bleeding causing that area to appear as a mass or cosmetic blemish.

At the time of birth, the presence of malformation is regarded as true vascular malformation which develops proportionally as the child grows but it neither develops rapidly during childhood nor disappears. They may become visible later in life as the flow of blood increases through abnormal associations between veins and arteries. Poorly developed lymphatic channels or veins can accumulate fluid and blood which may also leads to vascular malformations. They may disturb the normal functions of neck and head along with other areas of body causing cosmetic deformities.


Vascular malformations – abnormal clusters of blood vessels

During fetal development, abnormal clusters of blood vessels are formed which we term as vascular malformations. It is idiopathic and affects both male and female equallyAt the time of birth, lesion is always present. It might not be visible until days or even years after the birth of child but these lesions usually develops as the child grows. Sometimes they grow quite rapidly but typically they grow steadily and gradually during infancy. They are only be diminished when they are treated.


Capillary malformations

port-wine stain

Image: “port-wine stain” by UnKnown. License: CC BY-SA 3.0

A sharply defined flat vascular blemish of the skin is termed as capillary malformation usually known as a port-wine stain. It may appear as speckles forming little islands of color or may cover a huge surface area. They are commonly seen on head and neck but can be present at any part of the body. It is considered as idiopathic but it is assumed that it may arise due to abnormal development of minute blood vessels of skin during the embro phase of life.

The capillary malformations presence is not linked to medications or drugs taken throughout pregnancy or the experience of environment during that time. The number of blood vessels in capillary malformations is normal but the thickness of affected blood vessels is quite outsized causing an increase in flow of blood. As the vessels are quite close to the surface, the increased flow of blood causes the skin to appear pink to purple.

During the growth of the child, the affected blood vessels will persist to increase and thicken leading to a darkened lesion. Eventually, the clusters of minute, dilated venules give a lumpy impact to the skin. The growth rate of lesion may vary from person to person and can be delayed up to the age of 60.

Sturge-Weber syndrome CT

Image: “CT (without contrast) of the brain of a 20 month old child with Sturge-Weber syndrome demonstrating prominent subcortical white matter calcification.” by Frank Gaillard. License: CC BY-SA 3.0

Capillary malformations occurring on the upper eyelid and forehead can be related with lesions of the eye and brain (Sturge-Weber syndrome). Capillary malformations occurring in skin above spine can be linked with Cobb syndrome, which involves the meninges of spine. Capillary malformations within this particular area can be linked with spine’s other abnormalities which can be diagnosed through MRI. Capillary malformations situated in nose, forehead and upper lip can be linked with brain’s vascular abnormalities and should also be diagnosed.

Lymphatic malformations

Lymphatic malformation

Image: “Lymphangioma (Cystic Hygroma).” by Vardhan Kothapalli. License: Free Art License

Sponge-like collections of clear fluid within abnormal spaces and channels are called as lymphatic malformations. Compilation of surplus fluid from the tissues and its carrying into venous system by the help of minute vessels is the main job of lymphatic system. Lymphatic malformation causes a slow transfer of excess fluid thus leading to dilation and accumulation of vessels causing inflammation of affected area or may cause excessive enlargement of bones and soft tissues.

These lesions are usually seen in axilla and neck but can occur at any part of body. In a number of areas the dilated lymphatic vessels be likely to appear tiny than other areas. Lesions can be deep or superficial, and diffuse or localized. They gradually increase in size but may develop rapidly sometimes. Trauma or infection can result in abrupt but transitory enlargement.

Lymphatic malformation is idiopathic but it is assumed that it may occur due to abnormal development of lymphatics during development of fetus and is not affected by drugs or environmental exposure during pregnancy.

Venous malformations

Abnormally dilated or developed veins either deep or superficial forms venous malformations. They are the most general form of asymptomatic vascular lesion. They are naturally present at the time of birth but are rarely seen until weeks or years even till adulthood.

Venous malformation develops gradually and steadily into enlarged veins. However, infection, surgery, hormonal changes or trauma linked with puberty, menopause or pregnancy may result in swift enlargement. Lesions can be present in the mucous membrane or in any organ counting, bowel, brain, spleen or liver.

It is also considered idiopathic but is thought that decrease in smooth muscle’s cell in vein can be a vital cause of it. However, exposure to drugs and environmental factors during pregnancy has no impact although alterations within the genes responsible for smooth muscle and endothelial cell communication has been found.

Arteriovenous malformations (AVM)

aterial venous malformation of the left kidney

Image: “An aterial venous malformation of the left kidney and a simple cyst of the right kidney” by James Heilman, MD. License: CC BY-SA 3.0

Intervening capillary bed lack can cause direct associations among arteries and veins that leads to localized or diffuse vascular lesions resulting in an arteriovenous malformation. Localized lesions are likely to be seen on neck and head, often emerge as vascular light stains at birth and usually do not expand until adolescence or early childhood.

Lesions are often seen on abdomen, chest or limb, which may not be noticeable until later in childhood for they expand with time. Lesions are noticeable in inner organs, which may be localized or diffused. They may include organs such as the liver, bowel, brain or in lungs. Lesions happening in the brain are common arteriovenous malformation. They are originally silent and their symptoms depending upon their rapid enlargement.

Idiopathic is the specific reason of all arteriovenous malformations; but they are considered due to irregular development of the usual arterial-capillary-venous associations during early stage of developing life.

Genetic abnormalities are linked with arteriovenous malformations such as Rasa.1 mutations and PTEN mutations. The PTEN gene is concerned in typical vascular enlargement. A alteration in PTEN would cause abnormal angiogenesis which explains the occurrence of AVMs.

Exposure of drugs and environmental factors during pregnancy is not associated with arteriovenous malformations.

Combined vascular malformations

Two or more kinds of vessel abnormalities are defined as a combined vascular malformation. They are four kinds of lesions (venous, capillary, arteriovenous or lymphatic) and can be combined.

Joint malformations are typically accompanied by overdevelopment of tissues (fat, muscle and skin) and bones. While patients may experience some additional skinny abnormalities and particular growth undergrowth.

The majority of combined malformations engage limbs, but other parts of body can also be involved. It is considered idiopathic but it is assumed that abnormal development of various blood vessels directs in adefined anatomical area during early phase of life can be a cause of combined malformations.

Clinical Features

Vascular malformation tends to be clinically inactive until the mentioned affair occurs. Its diagnosis generally is found at the time of the first attack or hemorrhage. People with vascular malformation have a previous history of headaches. The headaches afterward may catch the form of archetypal migraine. If attacks have occurred one must be careful about seizure history. Seizures are partial, simple or secondarily generalized.

Investigations and Diagnosis

Vascular malformations are probably inclined by hormonal changes taking place during pregnancy and puberty and can also occur as a result of accumulation of blood or fluid in abnormally developed lymphatic channels or veins. Usually, there at birth of child and develop correlatively with the effected child, vascular malformations neither develops rapidly in childhood nor disappears.

Vascular malformations can become visible afterward in life as the stream of blood increases within abnormal associations among veins and arteries. Malformations deep within the body can be diagnosed through use of MRI.


Hemangiomas is different from true malformations in fact that most of the vascular malformations need treatment. Although each vascular malformations cannot be totally eradicated, recent treatment techniques help in improvement of  the look of the patient and simplify the symptoms of pain, inflammation and bleeding. Numerous adults and children having vascular malformations gain high level of performance and achievement at college, school and indifferent sports.

As true vascular malformations are exceptional and intricate, best possible outcomes are achieved in their treatment and diagnosis at specialized centers. Each patient with a vascular malformation is exclusive and needs the interest of specific training, experience and skills of professionals in this area and their way to the highly developed apparatus and resources.

Treatment selection for vascular malformations

The cerebro-vascular pediatric team and the multidisciplinary team gives the most modern and highly developed treatment for all sort of vascular malformations which are cautiously slated for right problem, location, age and symptom of patient. These treatment modalities hold:


The “glues” or particles are used to close the abnormally developed blood vessels.  This invasive method is called as embolization. Even though this method can seal the abnormality in few patients, in some other patients the malformation is needed to be eradicated surgically or with a radio surgery in which particular type of radiations are used. In such cases, embolization former to each of these technique can minimize the malformation and assist in minimizing the risk of flow of blood if surgical abolition is necessary.

Laser treatment

It has a great impact for treating venous malformations that are superficial or the deep lesion having superficial component. Physicians must use their extensive knowledge in navigating the therapeutic variety that is exclusive to every patient. The lasers used are competent for efficiently decreasing the bluish streaking of the inside layer of the skin and lips and the mouth.

A cooling device is used jointly with laser so that the skin is feasible and safe to cure the vascular malformation through the intact skin. Recently, laser treatment approach is often shared with sclerotherapy as well as surgery for an useful treatment of composite venous malformations.



Image: “Sclerotherapy” by BruceBlaus. License: CC BY-SA 4.0

This therapy is frequently employed in treating vascular malformations as well as lymphatic malformations. A body is injected into the anomalous vessel via skin. The body can be among one of few that are competent to infuriate the vessel that leads towards creation of a blood lump and this blood lump will successfully discontinue the stream of blood via the vessel and the soreness of the internal wall will obliterate the vessel.


Surgical elimination of a vascular malformation is phased or it will work probably in single operation. Recently, physicians have perfected a treatment in which the lesion is initially cured with sclerotherapy and later within 48 hours, malformation is surgically eliminated.

In count to sclerotherapy, thereby a reduced risk of rigorous blood wastage during surgery. This method lowers the amount of treatments required, since the vicinity that endures sclerotherapy is being eliminated. The outcome of this joint treatment has been tremendous and we competent to eradicate injury that were formerly considered untreatable.

Additionally, experience shows large malformations cured with sclerotherapy, evading bulky disfiguration marks, than ordinary surgery. In accordance, microcystic (small cysts) lesions, reappearance after surgery are generally high and several procedures are typically necessary. The exercise of sclerotherapy with technique known as gravity technique has transformed the treatment.

Only surgery can be a choice alone after embolization for vascular malformations. The combination is chosen; embolization is pursued 48 hours later of nidus by surgical resection. However, if the condition is widespread it is significant to operate only sufficient tissue to prevent reappearance, but evade disfigurement.

High-yield Notes of Vascular Malformation & Tumors for USMLE

Vascular Tumors (Hemangiomas) Vascular Malformations
Presence at birth Not present at birth but appear postnatally There are errors of morphogenesis and are presumed to occur during intrauterine life → Most present at birth
Natural history Phases:

  1. Proliferating: Grow rapidly during first year
  2. Involuting: Slow during childhood over 2–6 years.
  3. Involuted: By the age of 10 years
Proportionate growth; can expand
Cellular Endothelial hyperplasia Normal endothelial turnover
Skeletal changes
  • Occasional mass effect on adjacent bone
  • Rare hypertrophy
  • Slow-flow: Distortion, hypertrophy, or hyperplasia
  • Fast-flow: Destruction, distortion, or hypertrophy

Vascular tumors

Hemangioma of Infancy (Strawberry Hemangioma) Most common tumor of infancy with  F : M ratio (3:1)

Clinical features

  • Description:
    • Soft bright red (more violaceous when deeper), sharply demarcated, raised lesions
    • Appearing in first 2 months → rapidly expanding → then involuting by  age 5–9 years
  • Distribution:
    • Lesions are usually solitary and localized or extend over an entire region
    • Head & neck 50 %/trunk 25 %. Face, trunk, legs, oral mucous membrane

Special presentations: deep hemangioma (formerly cavernous cemangioma)

  • Consist of dilated vascular spaces with thin-walled endothelial cells
  • Presentation as soft blue, compressible masses up to a few centimeters in size
  • Cavernous hemangiomas may appear on the skin, viscera, deep tissues, mucosa  If it involves the larynx it can cause obstruction
  • Less likely to regress spontaneously than capillary hemangiomas
  • Cavernous hemangiomas of brain & viscera are associated with von Hippei-Lindau disease


  • No intervention is the best: because spontaneous resolution gives the best cosmetic results
  • Treatment is indicated if hemangioma 1) Ulcerate  2) Obstruct vital structures 3) If life threatening as hear failure
    • Surgical: 1) Continuous wave or pulsed dye laser 2) Cryosurgery
    • Medical: 1) Intralesional and systemic high-dose glucocorticoids 2) Interferon α (IFN-α) 3) Propanolol
Pyogenic Granuloma
  • Very common solitary eroded vascular nodule that bleeds spontaneously or after minor trauma
  • Appears as bright red, dusky red, violaceous, or brown-black papule with a collar of hyperplastic epidermis at the base

Vascular malformations

Capillary malformation (CM)

Port-Wine Stain (Nevus flammeus) Clinical features

  • Irregularly shaped, red or violaceous, macular CM that is present at birth and never disappears spontaneously
  • Tends to increase in to size of the child → becomes raised & nodular causing significant disfigurement.
  • Distribution: 
    • Most commonly involve the face in the distribution of the trigeminal nerve, usually the superior & middle branches
    • Mucosal involvement of conjunctiva & mouth may occur

Syndromic CM

  • Sturge-Weber syndrome (SWS) is the association of Port-Wine Stain in the trigeminal distribution with:
    • Eye: Vascular malformations in the eye and
    • Brain: Leptomeninges & superficial calcifications of the brain
  • Klippel-Trénaunay-Weber syndromeMay have an associated PWS overlying the deeper vascular malformation of soft tissue & bone
Spidar Angioma (Spider Nevus)
  • Consist of a bright red central papule (dilated central arteriole)  surrounded by telangiectatic network of dilated capillaries
  • Associated with hyperestrogenic states, such as pregnancy, in patients receiving estrogen therapy, e.g., oral contraceptives, or in those with hepatocellular disease
  • May regress spontaneously
Cherry Angioma (Cherry Hemangiomas) Senile Hemangiomas
  • Appears during third or fourth decade of life
  • Do not regress spontaneously because their number often increases with age
  • Always cutaneous and not found on the mucosa or deep tissues
  • Description: Sharply circumscribed areas of congested capillaries & post-capillary venules in papillary dermis

Popular Exam Questions

The correct answers can be found below the references.

1. A 3 months old infant has soft bright red, sharply demarcated, raised lesions over the head and neck. Hemangioma of infancy was diagnosed. The best next step in management of the infant is what?

  1. No intervention, as it will involute by  the age of 5 years
  2. Laser treatment
  3. Sclerotherapy
  4. Surgical removal

2. Sturge-Weber syndrome (SWS) is the association of Port-Wine Stain in the trigeminal distribution with what?

  1. Intraventricular hemorrhage
  2. Cavernous hemangiomas of brain   
  3. Vascular malformations in the eye   
  4. Vascular malformation of soft tissue & bone

3. Vascular tumors (hemangiomas) are characterized by its presence…

  1. …in post-natal infant.
  2. …in intrauterine life.
  3. …at birth.
  4. …in adulthood.
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