title: Appropriate indications for venous duplex ultrasonographic examinations.
abstract: BACKGROUND
  Because of the rapid growth in requests for lower extremity venous duplex ultrasonographic examinations, we have evaluated test results to determine the appropriate indications for testing and whether there is overuse of this technique.
  
  
  METHODS
  We reviewed the records of all patients who had duplex ultrasonogram during an 18-month period to rule out deep vein thrombosis (DVT). Test outcome was evaluated with data on the age, gender, outpatient or inpatient status, duration of symptoms, physical findings, and risk factors of the patients.
  
  
  RESULTS
  We reviewed 3474 examinations; 1265 outpatients and 1231 inpatients were evaluated to rule out DVT, and 978 patients were evaluated to rule out a source of pulmonary embolism. More outpatients were female, and they tended to be younger; outpatients also had more acute femoropopliteal DVT. The presence of sudden onset of unilateral swelling was a strong predictor of acute DVT in all three groups: 52% of such patients were found to have DVT. Mild unilateral symptoms with a coexistent risk factor was associated with a 10% to 20% prevalence of acute DVT. Chronic unilateral swelling was associated with acute DVT only with a coexistent risk factor and only in 1% of such patients. Bilateral swelling was only associated with acute DVT in the inpatient population, with 17% of studies having positive results. If calf tenderness was the only symptom with no associated risk factors, seven (1.6%) of 415 patients had acute DVT and six of these were tibioperoneal. No patients with cellulitis or isolated joint pain had acute DVT. With clinically suspected pulmonary embolism in patients without associated symptoms or risk factors, 7 (1.5%) of 447 studies showed tibioperoneal disease with no acute femoropopliteal disease.
  
  
  CONCLUSIONS
  The physical examination and clinical history of the patient remain important indicators of the presence (or absence) of lower extremity DVT and can guide the appropriate use of duplex ultrasonography for the diagnosis.
authors.affiliation: Department of Surgery, William Beaumont Hospital, Royal Oak, Mich. 48073, USA.
authors.forename: J L
authors.initials: JL
authors.lastname: Glover
authors.forename: P J
authors.initials: PJ
authors.lastname: Bendick
mesh_terms: D000367:Age Factors; D004487:Edema / Q000000981:diagnostic imaging; D005260:Female; D006801:Humans; D007297:Inpatients; D007866:Leg / Q000098:blood supply / Q000000981:diagnostic imaging; D008297:Male; D010045:Outpatients; D015995:Prevalence; D012307:Risk Factors; D013927:Thrombosis / Q000000981:diagnostic imaging* / Q000453:epidemiology; D018616:Ultrasonography, Doppler, Duplex; D014680:Veins / Q000000981:diagnostic imaging*