title: A retrospective study of the value of indirect CT venography: a British perspective.
abstract: OBJECTIVE
  The aim of this study was to establish the value of indirect CT venography (CTV) in clinical practice within the UK.
  
  
  METHODS
  804 combined CT pulmonary angiogram and CTV studies were retrospectively reviewed. CTV was performed 180 s after the injection of contrast using an incremental technique with a 5-mm collimation and a 5-cm interspace between images extending from the iliac crests to the tibial plateaus.
  
  
  RESULTS
  12.9% of studies had isolated pulmonary emboli (PE), 3.0% had both a PE and deep vein thrombosis (DVT) and 1.1% had an isolated DVT. The proportion of positive cases diagnosed by CTV alone was 6.6%.
  
  
  CONCLUSIONS
  In a UK-based practice, the incidence and the proportion of isolated DVT diagnosed by CTV are lower than expected from published data. An analysis of possible causes for this is made within the paper.
authors: Department of Radiology, Leeds Teaching Hospital NHS Trust, Leeds, UK.
authors: S
authors: S
authors: Slater
authors: D
authors: D
authors: Oswal
authors: B
authors: B
authors: Bhartia
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015331:Cohort Studies; D005260:Female; D006801:Humans; D007297:Inpatients / Q000706:statistics & numerical data; D008297:Male; D008875:Middle Aged; D010045:Outpatients / Q000706:statistics & numerical data; D010690:Phlebography / Q000009:adverse effects / Q000379:methods* / Q000706:statistics & numerical data; D011655:Pulmonary Embolism / Q000000981:diagnostic imaging*; D011829:Radiation Dosage; D011857:Radiographic Image Interpretation, Computer-Assisted; D012189:Retrospective Studies; D012680:Sensitivity and Specificity; D014057:Tomography, X-Ray Computed / Q000009:adverse effects / Q000379:methods* / Q000706:statistics & numerical data; D006113:United Kingdom; D020246:Venous Thrombosis / Q000000981:diagnostic imaging*; D055815:Young Adult