The role of routine IVC/Iliac vein and Infra-popletial venous duplex scans

Introduction.The routine evaluation for lower extremity deep vein thrombosis(DVT) usually involves the femoral/popletial veins with no regard to the more proximal inferior van cava and iliac(IVC/Iliac) veins or the more distal(Infra-popletial) veins.In this study,we attempted to evaluate the role of routine scanning of these segments.Materials and methods.In this study we reviewed 1624 lower extremity venous duplex studies performed between January 2008 and July 2008.All studies included routine evaluation of the IVC/Iliac and infra-popletial vein segments.Methods.For assessment of the IVC/Iliac vein segments,the study population was divided into two groups. The first group included patients in which those vein segments were completely visualized and evaluated.The other group included patients with incomplete visualization.The incidence of DVT and PE was noted.For evaluation of the infra-popletial segments the study population was divided into two groups.The first group included patients with DVTs isolated to the infra-popletial segments.The other group included patients with infra-popletial DVTs with evidence of more proximal thrombi.Results.IVC/Iliac vein segments:These segments were completely evaluated in 1270(78.2%) duplex studies with evidence of IVC/Iliac vein DVTs in 37(2.9%).In 354(21.8%) studies the evaluation was incomplete due to improper visualization of the IVC mostly due to bowel gas.Despite that, evidence of Iliac vein DVT was noted in 18(5.1%) studies.In total,routine scanning of the IVC/Iliac vein segments resulted in the detection of 55(3.38%) additional acute DVTs with evidence of PE in 5 (Incidence :9.1%).Thrombosis was limited to the IVC/Iliac segments in 5(9.1%) studies with evidence of PE in one (Incidence:20%).The rest of the study population had evidence of acute femoral-popletial DVTs in 70(4.3%) studies with evidence of PE in 12 (incidence of 17.1%).(Fisher’s p=0.193) Infra-popletial segments:145 Infra-popletial DVTs were detected, of which50(34.5%) were isolated to the infra-popletial segments with evidence of PE in 3(incidence:6%).The rest of the study population had evidence of acute femoral-popletial DVTs in70(4.3%) studies with evidence of PE in12(incidence of 17.1%).(Fisher’s p=0.094)Conclusion:Routine scanning of the IVC/Iliac veins and infrapopliteal veins resulted in the detection of a significant number of DVTs.