Jp. Garino et al., DEEP VENOUS THROMBOSIS AFTER TOTAL JOINT ARTHROPLASTY - THE ROLE OF COMPRESSION ULTRASONOGRAPHY AND THE IMPORTANCE OF THE EXPERIENCE OF THETECHNICIAN, Journal of bone and joint surgery. American volume, 78A(9), 1996, pp. 1359-1365
We evaluated the influence of the expertise of the technician on the a
ccuracy of compression ultrasonography as a screening test to;detect p
ostoperative deep venous thrombosis in patients who had had primary or
revision arthroplasty of the hip or the knee, The study was performed
in two phases on two groups of patients who were evaluated with both
compression ultrasonography and conventional venography. All of the pa
tients received prophylaxis for deep venous thrombosis, In the first p
hase of the study, adequate venograms and ultrasonograms were made for
126 extremities (121 patients), Venography demonstrated seven thrombi
in the proximal veins, Only three ultrasonograms were considered posi
tive. Ultrasonography had a sensitivity of 0 per cent because none of
the seven proximal thrombi identified with venography were detected wi
th ultrasonography, Three ultrasonograms were false-positive (that is,
the ultrasonogram was positive and the venogram was negative), so the
specificity was 97 per cent, The accuracy of compression ultrasonogra
phy was 92 per cent, Both tests were performed on a second group of ei
ghty-seven extremities (eighty-four patients), Proximal clots were det
ected with venography in five extremities, The ultrasonogram was posit
ive for seven extremities, including the five in which a clot had been
identified with venography, There were no false-negative and two fals
e-positive results. In this phase of the study, ultrasonography had a
sensitivity of 100 per cent, a specificity of 98 per cent, and an accu
racy of 98 per cent, The only difference that was identified between t
he two groups of patients was the experience of the ultrasonography te
chnician, It appears that the reliability of compression ultrasonograp
hy is directly dependent on the experience of the technician.