title: Enhanced ultrasound with navigation leads to improved liver lesion identification and needle placement.
abstract: BACKGROUND
  The aim of this study was to evaluate whether enhanced three-dimensional ultrasound (US) could increase the accuracy and efficacy for liver tumor identification and needle placement.
  
  
  METHODS
  In a prospective study, 30 surgeons of various training levels were evaluated for lesion identification success and accuracy of needle placement. All surgeons were evaluated for time (seconds) to identify the liver lesions in an artificial model and placement of needles after review of a 3-phase computed tomography scan of the liver, first using standard B-mode US and then using E-3DUS.
  
  
  RESULTS
  Participants included 10 hepato-pancreatico-biliary surgeons, 5 surgical fellows, 10 postgraduate years 4 and 5 surgical residents, and 5 postgraduate year-3 residents. Liver lesions were correctly identified in 73% of the cases using B-mode US alone and 100% in E-3DUS. The mean time to identification using B-mode was 51.9 s (standard deviation ± 37.1), which was significantly longer than with E-3DUS (time, 17.9 s, standard deviation ± 10.7; P = 0.002). There was significant improvement in time-to-lesion identification using E-3DUS across all training levels (P ≤ 0.002). There was also a significant reduction in time for accurate needle placement across all training levels (mean reduction of 60%, with enhanced accuracy [P = 0.001])
  
  
  CONCLUSIONS
  E-3DUS significantly enhances lesion identification regardless of size and enhances needle accuracy for all surgeons. This adjunctive system should be considered for both training and for all complex liver tumor ablations.
authors.affiliation: Department of Surgery, University of Louisville, Louisville, Kentucky. Electronic address: Robert.Martin@louisville.edu.
authors.forename: Robert C G
authors.initials: RC
authors.lastname: Martin
authors.affiliation: Department of Surgery, University of Louisville, Louisville, Kentucky.
authors.forename: Durham Alan
authors.initials: DA
authors.lastname: North
mesh_terms: D055011:Ablation Techniques / Q000295:instrumentation; D006801:Humans; D021621:Imaging, Three-Dimensional / Q000379:methods*; D008113:Liver Neoplasms / Q000000981:diagnostic imaging* / Q000601:surgery; D008953:Models, Anatomic; D009339:Needles; D011446:Prospective Studies; D013997:Time Factors; D014057:Tomography, X-Ray Computed; D018084:Ultrasonography, Interventional / Q000379:methods*
keywords: Enhanced ultrasound; Intraoperative imaging; Liver ablation with navigation; Three-dimensional ultrasound with navigation; Training requirements