Vascular malformations are abnormal growths consisting of arteries, veins and/or lymphatic vessels that can occur anywhere in the body.  These vessels do not develop in a normal ordered pattern but instead develop in an uncontrolled mesh-up into a growth.   These malformations are usually non-cancerous but can grow and invade the tissues surrounding the malformation.  

Common types of vascular malformations:

  • Venous malformations look like bluish or skin-coloured soft lumps under the skin
  • Arterio-venous malformations are usually more prominent at presentation as they are associated with high blood flow in the affected part. The patient may feel a pulsation or thrill at the site of the Arterio-venous malformation.   
  • Lymphatic-venous malformations tend to involve the superficial lymphatic channels of the skin as well as veins  

These malformations can occur anywhere in the body. Some of the common areas affected include inside the brain, the  head and neck region neck region as well as the upper and lower limbs.  Some patients may also develop malformations in the pelvis as well as in internal organs such as liver and kidneys. Regardless of type and depending on how long the malformation has been growing, they sometimes can be extremely large causing gross enlargement or deformity of the affected part.

Vascular malformations are believed to be congenital in nature.  However there have been no evidence showing a genetic predisposition meaning it is NOT inheritable in nature.  We see patients as young as neonates and into their teenage years.  However, a significant number of patients only notice the malformation or have it diagnosed at a later age (30s to 50s) without any symptoms or signs when they were younger.


Symptoms caused by the malformation depend on their location in the body as it usually grows and invades the surrounding tissue.  A vascular malformation inside the brain can bleed (causing a stroke), cause seizures (fits) due to pressure on brain tissue or press on a nerve in the brain causing nerve deficits.  . Malformations in the face and limbs can present as  a soft lump in the that may be obvious and cosmetically unpleasant . There may also be associated pain with progressive increase in size over time with skin discolouration. They can also undergo repeated bleeding and can invade surrounding body structures, causing pain and loss of limb function.


Diagnosis usually is made after a clinical examination.  An MRI/MRA  may be done to determine the nature of the malformation (arterial predominant vs venous v lymphatic) as well as the degree of surrounding tissue involvement.


  • Surgical excision of the malformation – can recur and grow again if not completely excised and may be disfiguring if it involves large areas of tissue
  • Minimally invasive methods to stop the growth of the malformation. Depending on the size of the malformation, some patients may require a few sessions of such treatment. These methods include:
    • blocking the malformation arteries (embolization) with injected glue or metallic coils
    • injecting the vein/ lymphatic components with scarring solutions (sclerotherapy) or alcohol.