Deep vein thrombosis CT

Editors-in-Chief: C. Michael Gibson, M.S., M.D. Associate Editor-In-Chief: Ujjwal Rastogi, MBBS [mailto:urastogi@perfuse.org]

Overview
More than 90% of all Pulmonary Embolism arise from thrombi within the large deep veins of the legs, typically the popliteal vein and the larger veins above it. Since Pulmonary embolism and deep vein thrombosis are different spectrum of the same disease, CT venography of the pelvis and lower extremities is often incorporated into the CT angiography PE protocol to identify or exclude concurrent deep venous thrombosis.

A study had showen that CTPA positively diagnosed acute PE, in 14% to 44% patient having non-diagnostic V/Q scan and with normal lower extremity ultrasound imaging. Another randomized control trial involving seventy patients with clinically suspected pulmonary embolism, showed that, compared to sonography, CT venography in addition to CT pulmonary angiography is a relatively accurate method for evaluation of femoropopliteal venous thrombosis.