Q: What is a congenital vascular malformation?
A: Congenital vascular malformation,often referred to as "CVM" among clinicians, is an inborn defect resulting from the arrest of normal development of the vascular structure, and/or failure of orderly resorption of the embryologic primitive vascular element and subsequent persistence of the immature anomalous vascular structure. In other words, when this primitive vascular structure, which is essential for the rapid development of embryonal life, should fail to continue to develop normally and/ or remains even after birth following failure of the normal resorption of this embryonal vascular structure (which is no longer needed after birth), this anomalous vascular structure/embryonal remnant jeopardizes normal life after birth. Therefore, depending upon the stage of the embryologic morphogenesis at which the arrays stop, various types of vascular malformation can occur. Hence, "vascular malformation" seems to be enough to define this inborn abnormality without further addition of "congenital," because all vascular malformations are the result of an inborn error, after all.
Q: Is a congenital vascular malformation the same or different from a vascular anomaly?
A: Vascular malformation is one of two major categories belonging to vascular anomalies, together with vascular tumors. Vascular malformation is a pure inborn error which is obvious at the time of birth, since it started during embryonal development. Its clinical manifestations, however, are extremely variable depending upon the type of malformation (e.g., arterial, venous, AV shunting, mixed and lymphatic) and also on the location and degree of the involvement of the surrounding soft tissue, muscle, bone and skin, and may stay dormant for years. Therefore, all the vascular malformations should present at birth, by definition. Conversely, vascular tumor, often referred to as neonatal or infantile hemangioma, is a truly tumorous neovascular growth which develops in the post-natal period, generally within a few days to a few weeks after birth.
Q: How do you treat lymphatic malformation?
A: Lymphatic malformation is one of the most common forms of congenital vascular malformation (CVM). There are two different types of lymphatic malformation: truncular and extratruncular. The truncular form also is known as primary lymphedema, which reflects its clinical status, and the extratruncular form as cystic/cavernous lymphangioma.
The treatment principle for the truncular form of lymphatic malformation (e.g., aplasia or hypoplasia of the lymphatic system) is complete decongestive therapy, alone or in combination with sequential intermittent pneumatic compression. The clinical management of the truncular form of lymphatic malformation is, therefore, the same as for chronic lymphedema, except for the surgical aspect of treatment. However, whenever you encounter the truncal form of lymphatic malformation as primary lymphedema (e.g., Klippel-Trenaunay Syndrome), be careful not to overlook the possible involvement of the extratruncal form of lymphatic malformation and other types of congenital vascular malformation (such as venous malformation) as additional components affecting the same limbs.
Basic knowledge of lymphatic malformation, in general, especially the relationship between the truncal and extratruncal forms, is essential in order to handle the truncal form of lymphatic malformation safely as primary lymphedema.
The treatment principle of the extratruncal form of lymphatic malformation is different than that of the truncal form, but similar to those for other extratruncal forms of congenital vascular malformation. Sclerotherapy with ethanol and/or OK-432 (Picibanil) has proven to be quite useful, especially for cystic lesions. The conservative approach has to be adopted as the general principle of therapy, not only for the truncal form of lymphatic malformation, but also for the extratruncal form, that is, unless it seriously affects the quality of life or is life-threatening (e.g., proximity of the extratruncal lesion to the airway).
Although CVM specialists have been occupied with other serious CVMs– as venous malformation or arteriovenous malformation –neglecting relatively benign lymphatic malformation for decades, lymphatic malformation has been actively pursued lately in order to implement new concepts of genetic manipulation to correct defective genes of neolymphangiogenesis as a future treatment/prevention strategy of the truncal form of lymphatic malformation, as well.
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