Extended Compression Ultrasound Performed by Emergency Physicians: A Modified Compression Ultrasound Examination to Detect Superficial and Deep Lower Limb Thromboses in the Emergency Department

Compression ultrasound (CUS) is being used by an increasing number of emergency physicians for patients with suspected symptomatic deep venous thrombosis (DVT). Both the two-point and three-point CUS examinations are used with excellent sensitivity to rule out DVT. This technique has some limitations: distal DVTs are difficult to detect, and therefore a second examination is required about 1 week later to look for proximal progression of thrombosis. Furthermore, the superficial veins of the lower limbs are not routinely visualized when CUS examination is performed in the emergency department. Superficial vein thrombosis is common and has long been considered as a benign disease, however, this concept has been challenged. Superficial vein thrombosis can extend into the deep vein system and cause either DVT or pulmonary embolism.At our institutions, we have developed a modified CUS examination for the lower limbs, which we have called extended CUS, because it explores both the proximal deep veins and superficial veins.In this article, we describe this examination technique.