A PROSPECTIVE FOLLOW-UP-STUDY OF ACUTE DEEP VENOUS THROMBOSIS USING COLOR DUPLEX ULTRASOUND, PHLEBOGRAPHY AND VENOUS OCCLUSION PLETHYSMOGRAPHY

Objective. To study the extent of deep venous thrombosis (DVT) and thr ombus regression over time and to compare the results obtained with di fferent diagnostic techniques. Experimental design. A prospective foll ow-up study with repeated examinations during a 6-month period. Settin g. Patients studied at clinical vascular laboratories. Patients. Forty patients hospitalised for acute DVT. Thirty-six of these completed th e follow-up period. Measures. The diagnosis of DVT was confirmed with phlebographic and/or ultrasonographic techniques. The patient were the n re-examined with colour duplex ultrasound and venous occlusion pleth ysmography after one week, 3 months and 6 months and with phlebography after 1 week and 6 months. The extent of DVT and number of occluded s egments were determined with phlebographic and ultrasonographic techni ques. Venous occlusion plethysmography was used to evaluate the functi onal degree of outflow obstruction. Results. Colour duplex scanning at 3 months' and 6 months' follow-up showed that 55% and 74% of initiall y occlusive thrombi, respectively, were recanalised, with thrombus res olution occurring faster and more completely in those initially limite d to popliteal and/or calf level. Discrepancies between phlebography a nd duplex scanning were found in 6% (26/441) of venous segments invest igated by both methods, primarily concerning flow in the veins below t he knee. Conclusions. In comparison with phlebography, colour duplex s canning is an accurate method for evaluation and follow-up of patients with DVT. The non-invasive nature of colour duplex scanning makes thi s method extremely suitable for repeated studies and thus a potentiall y very valuable tool for both clinical and research studies of circula tory changes involved in acute and chronic DVT.