A Comparison of Real-Time Compression Ultrasonography with Impedance Plethysmography for the Diagnosis of Deep-Vein Thrombosis in Symptomatic Outpatients

It is now generally accepted that objective tests are mandatory in order to make the diagnosis of clinically suspected acute deep-vein thrombosis of the leg 1 – 3 . Currently, impedance plethysmography performed serially over a one-week period (to detect propagating thrombi in calf veins and nonocclusive thrombi) is considered the method of choice for the diagnosis of deep-vein thrombosis in symptomatic patients. This conclusion is based on several large clinical follow-up studies in which anticoagulant therapy was safely withheld from patients with repeatedly normal impedance plethysmograms 4 – 8 . In addition, an abnormal result proved to have a high degree of clinical . . .