Evalation of deep venous thrombosis in the lower limbs and pelvis. mr venography versus duplex doppler sonography

ABSTRACT

This study was designed to show the comparable diagnostic value of MR venography and color Doppler Sonography in the assessment of deep venous thrombosis [DVT]. Twenty five patients with clinically suspected DVT of the lower limb and pelvis were included in this study. Two Dimensional Time of Flight MR venography and color Doppler sonography were performed to all cases twelve hours before conventional venography. The data were collected prospectively and analyzed in blinded manner. In evaluating DVT in the pelvic region, MR venography was superior to color Doppler sonography, reported 91% sensitivity and 99.4% specificity versus 78% sensitivity and 98% specificity for Doppler sonography. MR venography and color Doppler sonography were 100% sensitive and 100% specific in evaluating DVT in the thigh region. While, MR venography surpassed both techniques in evaluating DVT in the calf veins, with sensitivity and specificity of 87.5% and 99% respectively versus 67% sensitivity and 97% specificity for color Doppler sonography. MR showed more ability to assess the extent of thrombus. MR venography showed 47 collateral vessels, where as only 40 were dedected by contrast enhanced venography. The combined readings of axial and maximum intensity projection MR images was significantly modified the levels of sensitivity and specificity of MR venography. MR venography was more sensitive than color Doppler sonography in evaluating pelvic and calf DVT. Where as both techniques were equivalent in evaluating femoro popliteal DVT. MR venography showed better demonestration of thrombus extension and collaterals