Triplex US in the diagnosis of asymptomatic deep venous thrombosis.
OBJECTIVE
To evaluate the accuracy of triplex ultrasound (TUS) compared with venography as a screening test for deep venous thrombosis (DVT), and to evaluate interobserver variation in the interpretation of the venographic studies.


METHODS
A total of 133 postoperative hip fracture patients, asymptomatic of DVT, were prospectively examined with TUS and venography. All venograms were reviewed blindly and in case of disagreement a consensus was arrived at.


RESULTS
The incidence of DVT was 20%, with isolated calf vein thrombi in 63% of the cases. There were 7 false-negative and one false-positive result/s at TUS, with a sensitivity of 74%, specificity of 99% and accuracy of 97%. The kappa values ranged from 0.58 to 0.82. The false-negative results were all caused by missed calf vein thrombi in technically inadequate examinations. At sonography 2% of vein segments were noninterpretable, compared to 29% at venography.


CONCLUSIONS
Venous US is less sensitive as a test for DVT in this study of asymptomatic patients than in earlier studies on symptomatic patients. Still, sonographic screening of high-risk patients would be both effective and cost effective. Fresh thrombi may cause a false-negative compression test.
Mantoni
M
M
Department of Radiology/Ultrasound, Gentofte Hospital, Hellerup, Denmark.
Strandberg
C
C
Neergaard
K
K
Sloth
C
C
Jørgensen
P S
PS
Thamsen
H
H
Tørholm
C
C
Paaske
B P
BP
Rasmussen
S W
SW
Christensen
S W
SW
Wille-Jørgensen
P
P
D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D015588:Observer Variation; D010690:Phlebography; D011446:Prospective Studies; D012680:Sensitivity and Specificity; D016037:Single-Blind Method; D013924:Thrombophlebitis / Q000000981:diagnostic imaging*; D014463:Ultrasonography