Abstract:Objective:To discuss the clinical value of D-dimer(DD) testing in diagnosis of patients with deep vein thrombosis(DVT) of the lower extremity. Methods:An analysis retrospectively was made on the changes of DD testing in 106 cases of DVT at different periods after onset and different clinical stages of DVT, and DD testing in 99 patients with primary deep venous insufficiency(PDVI) as control group. Results:DD was higher in the acute stage of DVT, and gradually decreased with time in chronic DVT, and was negative in the patients with PDVI; the positive rate was up to 85.7% in the distal DVT. Conclusions:The DD testing can be used as one of the methods for diagnosis, prediction and prognosis of acute DVT，especially for diagnosis of distal DVT.