Underassessment of lower extremity deep venous thrombosis using color flow Doppler compared to compression sonography.

The aim of this paper is to compare the accuracy of color Doppler to compression sonography in the diagnosis of lower extremity deep vein thrombosis. Longitudinal color flow imaging was performed in 60 lower extremities in patients with clinically suspected deep venous thrombosis (DVT). The study was then repeated by a blinded examiner using transverse compression sonography. The results were then correlated. Thirty-five examinations were negative by both color flow and compression methods. Twenty thrombi were diagnosed on compression sonography, while only 13 were diagnosed by the color flow method. Thirty-five percent of thrombi were missed using color flow imaging alone. We conclude that compression sonography should remain an integral part of the assessment of lower extremity DVT, as a significant number of thrombi might be overlooked using longitudinal color flow imaging alone. This is especially true in non-occlusive thrombi that are adherent to the vessel wall.