COLOR DOPPLER FLOW IMAGING ULTRASONOGRAPHY VERSUS VENOGRAPHY AS SCREENING METHOD FOR ASYMPTOMATIC POSTOPERATIVE DEEP VENOUS THROMBOSIS

Objective: To evaluate colour Doppler flow imaging ultrasonography (CD FI), compared with venography, as a screening method for postoperative deep venous thrombosis (DVT) in a clinical trial on thromboprophylaxi s. Methods: Patients undergoing major abdominal or thoracic surgery we re prospectively screened for DVT by CDFI. Patients were examined preo peratively, and on postoperative days 1, 3, 7, 14, 21, and 28. When th e CDFI was positive venography was performed. Bilateral venography was performed on day 28 in all patients. The study group comprised 82 pat ients who underwent CDFI and venography on the same day: four because of suspected DVT (positive CDFI), and 78 on day 28 according to protoc ol, Results: DVT was detected by venography in seven patients, in thre e of whom CDFI was positive. CDFI was falsely positive in one case. Th ere were two popliteal and five calf DVTs, of which CDFI detected one and two, respectively. The sensitivity of CDFI was 43%, the specificit y 99%. The PVpos for CDFI was 75%, and the PVneg 96%, Conclusion: Due to low sensitivity, CDFI cannot stand alone as a screening method for asymptomatic postoperative DVT.