title: Evaluation of deep vein thrombosis with multidetector row CT after orthopedic arthroplasty: a prospective study for comparison with Doppler sonography.
abstract: OBJECTIVE
  This prospective study evaluated the ability of indirect 16-row multidetector CT venography, in comparison with Doppler sonography, to detect deep vein thrombosis after total hip or knee replacement.
  
  
  METHODS
  Sixty-two patients had undergone orthopedic replacement surgery on a total of 30 hip joints and 54 knee joints. The CT venography (scan delay time: 180 seconds; slice thickness/increment: 2/1.5 mm) and Doppler sonography were performed 8 to 40 days after surgery. We measured the z-axis length of the beam hardening artifact that degraded the image quality so that the presence of deep vein thrombosis couldn't be evaluated on the axial CT images. The incidence and location of deep vein thrombosis was analyzed. The diagnostic performance of the CT venograms was evaluated and compared with that of Doppler sonography as a standard of reference.
  
  
  RESULTS
  The z-axis length (mean +/- standard deviation) of the beam hardening artifact was 4.5 +/- 0.8 cm in the arthroplastic knees and 3.9 +/- 2.9 cm in the arthroplastic hips. Deep vein thrombosis (DVT) was found in the popliteal or calf veins on Doppler sonography in 30 (48%) of the 62 patients. The CT venography has a sensitivity, specificity, positive predictive value, negative predictive value and accuracy of 90%, 97%, 96%, 91% and 94%, respectively.
  
  
  CONCLUSIONS
  The ability of CT venography to detect DVT was comparable to that of Doppler sonography despite of beam hardening artifact. Therefore, CT venography is feasible to use as an alternative modality for evaluating post-arthroplasty patients.
authors.affiliation: Department of Radiology, Inha University, College of Medicine, Incheon, Korea.
authors.forename: Sung Su
authors.initials: SS
authors.lastname: Byun
authors.forename: Jeong Ho
authors.initials: JH
authors.lastname: Kim
authors.forename: Youn Jeong
authors.initials: YJ
authors.lastname: Kim
authors.forename: Yong Sun
authors.initials: YS
authors.lastname: Jeon
authors.forename: Yong Sun
authors.initials: YS
authors.lastname: Chun
authors.forename: Chul Hi
authors.initials: CH
authors.lastname: Park
authors.forename: Won Hong
authors.initials: WH
authors.lastname: Kim
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D019644:Arthroplasty, Replacement, Hip; D019645:Arthroplasty, Replacement, Knee; D016477:Artifacts; D005260:Female; D006801:Humans; D007866:Leg / Q000098:blood supply*; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D011446:Prospective Studies; D012680:Sensitivity and Specificity; D014057:Tomography, X-Ray Computed / Q000379:methods*; D014463:Ultrasonography; D020246:Venous Thrombosis / Q000000981:diagnostic imaging* / Q000209:etiology