A classification of congenital vascular defects was developed at the Seventh Meeting of the International Workshop on Vascular Malformations in Hamburg in 1988. This was based on the classifications of Malan et al and Degni et al.


Classification is by:

(1) type of defect

(2) form and subform


Types of defects:

(1) predominantly arterial

(2) predominantly venous

(3) predominantly lymphatic

(4) predominantly arteriovenous shunting or fistulae

(5) combined or mixed vascular defects



(A) truncular = embryonal dysplasia of differentiated vascular trunks

(A1) aplasia or obstructive (for Types 1 to 3) - aplasia, hypoplasia or stenosis

(A2) dilatation (for Types 1 to 3) - ectasia, as aneurysm (dolichomegaarteria), phlebectasia or lymphangiectasia

(A3) deep (for Type 4) - with or without aneurysms

(A4) superficial (for Type 4)

(A5) arterial and venous (for Type 5) - without arteriovenous shunt

(A6) hemolymphatic (for Type 5) - with or without arteriovenous shunt

(B) extratruncular = remnants of primitive capillary networks

(B1) infiltrating - diffuse, with or without arteriovenous shunts

(B2) limited - localized, with or without arteriovenous shunts (without - cavernous spaces)


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