Venous thromboembolism is not a rare disorder.The imaging methods mostly used nowadays to diagnose thrombosis and to determine the age of thrombus include ultrasonography,CT,magnetic resonance imaging,venography and nuclear medicine.Accurate determination of the age of thrombus is of great clinical value in guiding the clinical management,in evaluating the therapeutic results and in predicting the prognosis.This paper aims to make a comprehensive review of the above mentioned imaging examinations.

ObjectiveTo investigate the anatomical distribution of acute deep venous thrombosis (DVT) of the lower extremity,and compare different therapeutic methods including anticoagulation alone,thrombolysis through dorsal vein and interventional therapy.MethodsThe clinical data,venography and therapies of 204 acute DVT patients were retrospectively studied According to the distribution,DVT were classified into three types including peripheral,central and mixed types.According to the difference of the therapeutic method,each type of DVT was divided into three groups,Group A (37 patients) anticoagulation alone:Group B(55 patients) thrombolysis through dorsal vein:and Group C( 112 patients) interventional therapy.The results of different kind of treatment method in each type of DVT were evaluated before the patients were discharged and the Chi-square test was used for statistical analysis.Results There were 132 patients with DVT in the left lower extremity,62 in right lower extremity,and 10 in both extremities.The complication of pulmonary embolism (PE) occurred in 4,5 and 2 cases respectively,and the morbidity was 3.0％,8.1％ and 20.0％ ( x2 = 6.494,P = 0.039 ) respectively.There was significant statistical difference among them.There were 23 cases of peripheral type of DVT,48 central type and 133 mixed type.The complication of PE were observed in 2,5 and 4 cases respectively in each type.The morbidity was 8.7％,10.4％ and 3.0％ respectively ( x2 = 4.350,P = 0.114 ).There were no statistical significance among them.In the 23 cases of peripheral type DVTs,2 of 5 in group A and 11 of 18 in group B had excellent therapeutic response.In the 48 cases of central type of DVTs,1 of 10 in group A,2 of 5 in in group B and 26 of 33 in group C had excellent therapeutic response.There were statistically significant differences among groups A,B and C ( x2 = 16.157,P =0.000).In the 133 cases of mixed type DVTs,1 of 22 in group A,10 of 32 in group B and 65 of 79 in group C had excellent therapeutic response.There were statistically significant differences among group A,B and C ( 1,10,65 cases,x2 = 53.993,P =0.000).ConclusionsThe incidence of acute DVT involving the left lower extremity was higher than that involving the right one,and the majority of cases was of the mixed type.The treatment of choice for the central and mixed types was interventional therapy.Analysis of anatomical distribution of deep venous thrombosis can guide treatment planning.