EVALUATION OF THE PULMONARY EMBOLISM AND DEEP VEIN THROMBOSIS USING MD-CT AFTER TOTAL KNEE ARTHROPLASTY

Abstract

Combined multi-detector row CT (MD-CT) pulmonary angiography (CTPA) and lower extremity venography (CTV) is an effective method for detection of pulmonary embolism (PE) and deep vein thrombosis (DVT). However, the usefulness of this method after total knee arthroplasty (TKA) has not been reported. The aim of this study is to evaluate our screening program in the management of thromboembolism.

Over a 1.5-year period, 30 patients with primary TKA were examined using an MD-CT (Lightspeed ultra 16.GE) before and 7th day after operation. 25 seconds after intravenous administration of 320ml of contrast material, CTPA was performed with 1.25-mm collimation and CTV from the iliac crest to the ankles was done with 0.625-mm collimation 165 seconds after contrastmaterial injection. The mean age of the patients was 72.2 (53–80). Twenty patients had osteoarthritis, nine had rheumatoid arthritis and one osteonecrosis. All patients were received 4 weeks of warfarin therapy and prophylaxis.

PE was observed in A1+2, A3, A6, A9, A10 area. PE was most frequently detected in A10 area of pulmonary artery (6/30). While, DVT was detected in only popliteal vein (6/30). The incidence of PE was 30% (9/30)and DVT 20% (6/30). Both PE and DVT were observed in 3 patients, the incidence was 10% (3/30).

Combined CTPA and CTV is a safe and accurate diagnotic method for detecting PE and DVT after TKA, and the ability to directly visualize emboli of this system is effective as therapeutic tool.