Vascular malformations are a rare condition that occur from maldevelopment of blood vessels. They may consist of veins, lymphatics, arteries, capillaries or connections between any of these vessels.

They can occur anywhere on the body and are very variable in behavior depending on which type of blood vessels they originate from and where they are located. It needs to be determined if the malformation is of venous, arterial, capillary, lymphatic or mixed origin. It then needs be determined if the lesion has high flow blood or low flow blood. Malformations may also consist of abnormal vessel dilatations, spongy type lesions or cystic type lesions.

The cystic lesions may be large or small cavities and may consist of single or few cysts to numerous tiny cysts (microcystic lesions); the latter which can be difficult to treat completely. One needs to assess symptoms and how dangerous they are - i.e. whether they are pressing on a vital organ or could compromise a vital organ and what their risk of growth, bleeding or clotting is. Although a more conservative management was traditionally employed for malformations unless they were life or limb threatening ,there is a shift in thinking to be more aggressive in treatment and try to ‘cure’ them.