The degree of organisation of an intravenous thrombus is important for
therapeutic interventions and the postthrombotic damage. Changes in e
chogenicity have already been described in B-mode sonography. We inves
tigated 7 thrombosis in the jugular vein looking for intra-thrombotic
vessels that occur during the organisation. In 3 thrombosis arterial v
essels were found from the 12th to the 17th day. Such arterial vessels
appeared only in a short range of time and only in circum-script area
s of the thrombus. The intra-vitam documentation of arterial vessels i
n an organisating intravenous thrombus may give information about the
mechanism of thrombogenesis and about the degree of organisation.