title: Is bilateral ultrasound scanning of the legs necessary for patients with unilateral symptoms of deep vein thrombosis?
abstract: OBJECTIVE
  The purpose of this study was to determine the necessity of bilateral lower-extremity venous duplex ultrasound scanning in patients with unilateral symptoms of deep vein thrombosis (DVT).
  
  
  METHODS
  A retrospective review of 1080 bilateral venous duplex scans was performed. Patients were randomly selected from a total of 7922 studied between May 1998 and May 2000. Data on patient age, sex, comorbidity, and the reason for ultrasound scan were compiled. Forty percent (435/1080) of patients presented with unilateral symptoms of lower-extremity DVT. This group was further analyzed according to their status as inpatients or outpatients.
  
  
  RESULTS
  DVT was diagnosed in 26.9% (117/435) of the patients. Of the inpatients found to have DVT, the thrombus was confined to the symptomatic leg in 23.8% (38/159), thrombus was present just in the asymptomatic leg in 8/159 (5.0%), and thrombus was found in both legs in 8/159 (5.0%). In the outpatient group, thrombus was confined to the symptomatic leg in 21.0% (58/276) and found in both legs in 1.8% (5/276). None of the 276 outpatients had DVT isolated in the asymptomatic leg.
  
  
  CONCLUSIONS
  Routine bilateral lower-extremity venous duplex studies are not necessary in outpatients presenting with unilateral symptoms. In many outpatients, a single-limb study will suffice. If a patient is found to have a DVT on the symptomatic side, then we believe that a bilateral study is indicated. We do believe that routine bilateral scanning of inpatients remains justified. This algorithm may save technician time and increase vascular laboratory efficiency.
authors.affiliation: Division of Vascular Surgery, Northwestern University, Chicago, Illinois 60611, USA.
authors.forename: N D
authors.initials: ND
authors.lastname: Garcia
authors.forename: M D
authors.initials: MD
authors.lastname: Morasch
authors.forename: J L
authors.initials: JL
authors.lastname: Ebaugh
authors.forename: S
authors.initials: S
authors.lastname: Shah
authors.forename: D
authors.initials: D
authors.lastname: Blackburn
authors.forename: P
authors.initials: P
authors.lastname: Astleford
authors.forename: J S
authors.initials: JS
authors.lastname: Matsumura
authors.forename: J S
authors.initials: JS
authors.lastname: Yao
authors.forename: W H
authors.initials: WH
authors.lastname: Pearce
mesh_terms: D000465:Algorithms; D005260:Female; D005268:Femoral Vein / Q000000981:diagnostic imaging; D006801:Humans; D008297:Male; D008875:Middle Aged; D011152:Popliteal Vein / Q000000981:diagnostic imaging; D012189:Retrospective Studies; D018616:Ultrasonography, Doppler, Duplex; D020246:Venous Thrombosis / Q000000981:diagnostic imaging* / Q000453:epidemiology