Reviewed by Brian R. Robinson, MD
A Congenital Vascular Malformation (CVM) is a type of birthmark or congenital growth composed of blood vessels. There are three different types of malformations and they are named according to which type of vessel predominates: capillaries, veins, or lymphatic vessels. CVM of the vein, for example, is called venous malformation.
CVMs occur as a result of abnormal blood vessel formation during embryonic life. Vascular malformations occur in less than 1% of newborns. Because there are so many types of CVMs, it is difficult to determine how many are of the venous type.
CVMs are not necessarily apparent at birth. They do not have a rapid growth phase and enlarge proportionately with the growth of the child. They never regress spontaneously and may become more apparent later in life.
CVM lesions involving the eyes, respiratory tract, and extremities may cause aesthetic and/or functional problems for the patient, and in turn may require treatment.