title: Laparoscopic ultrasonography versus intra-operative cholangiogram for the detection of common bile duct stones during laparoscopic cholecystectomy: a meta-analysis of diagnostic accuracy.
abstract: BACKGROUND
  Routine intra-operative cholangiography (IOC) during laparoscopic cholecystectomy is often not performed because of increased operative time, radiation, and failure rate. Laparoscopic ultrasound (LUS) is a less invasive alternative but studies comparing it to IOC have been of small sample size. This study aims to assess the diagnostic accuracy of LUS in detecting common bile duct (CBD) stones compared to IOC.
  
  
  METHODS
  This meta-analysis was executed and reported in accordance with the Preferred Reporting Items for Systematic Reviews and Meta- Analyses (PRISMA) statement. 11 comparative studies (1994-2013) reporting on 12 patient groups were included. A bivariate model for diagnostic meta-analysis was used to attain overall pooled sensitivity and specificity for IOC and LUS, and their relationship assessed using a hierarchical summary receiver operating characteristic model with meta-regression.
  
  
  RESULTS
  IOC had a pooled sensitivity of 0.87 (95% CI 0.77-0.93) and a pooled specificity of 0.99 (95% CI 0.98-0.99) with no significant heterogeneity. The diagnostic Odds Ratio (OR) was 442 (95% CI 196-997) and pooled weighted Area Under the Curve (AUC) was 0.99 (95% CI: 0.98-1.0). LUS had a pooled sensitivity of 0.87 (95% CI 0.80-0.92) and a specificity of 1.00 (95% CI 0.99-1.00). Heterogeneity was significant for specificity results. The diagnostic Odds Ratio (OR) was 1171 (95% CI 372-3689) and the pooled, weighted AUC was 1 (95% CI: 0.99-1). Meta-regression did not identify factors that significantly predict diagnostic accuracy.
  
  
  CONCLUSIONS
  LUS is a potentially useful imaging modality to confirm the absence of CBD stones without needing to cannulate the biliary system.
authors.affiliation: Minimal Access Unit, The Christie NHS Foundation Trust, Wilmslow Road, Manchester M20 4BX, UK. Electronic address: omer.aziz@christie.nhs.uk.
authors.forename: Omer
authors.initials: O
authors.lastname: Aziz
authors.affiliation: Department of Surgery and Cancer, Imperial College London, 10th Floor QEQM Building, St. Mary's Hospital, London W2 1NY, UK.
authors.forename: Hutan
authors.initials: H
authors.lastname: Ashrafian
authors.affiliation: Department of Surgery and Cancer, Imperial College London, 10th Floor QEQM Building, St. Mary's Hospital, London W2 1NY, UK.
authors.forename: Catherine
authors.initials: C
authors.lastname: Jones
authors.affiliation: Department of Surgery and Cancer, Imperial College London, 10th Floor QEQM Building, St. Mary's Hospital, London W2 1NY, UK.
authors.forename: Leanne
authors.initials: L
authors.lastname: Harling
authors.affiliation: Department of Surgery and Cancer, Imperial College London, 10th Floor QEQM Building, St. Mary's Hospital, London W2 1NY, UK.
authors.forename: Sacheen
authors.initials: S
authors.lastname: Kumar
authors.affiliation: Department of Surgery and Cancer, Imperial College London, 10th Floor QEQM Building, St. Mary's Hospital, London W2 1NY, UK.
authors.forename: George
authors.initials: G
authors.lastname: Garas
authors.affiliation: Department of General Surgery, Lister Hospital, Coreys Mill Lane, Stevenage, Hertfordshire SG1 4AB, UK.
authors.forename: Thomas
authors.initials: T
authors.lastname: Holme
authors.affiliation: Department of Surgery and Cancer, Imperial College London, 10th Floor QEQM Building, St. Mary's Hospital, London W2 1NY, UK.
authors.forename: Ara
authors.initials: A
authors.lastname: Darzi
authors.affiliation: Department of Hepatobiliary Surgery, Hammersmith Hospital, Du Cane Road, London W12 0HS, UK.
authors.forename: Emmanouil
authors.initials: E
authors.lastname: Zacharakis
authors.affiliation: Department of Surgery and Cancer, Imperial College London, 10th Floor QEQM Building, St. Mary's Hospital, London W2 1NY, UK.
authors.forename: Thanos
authors.initials: T
authors.lastname: Athanasiou
mesh_terms: D002758:Cholangiography; D017081:Cholecystectomy, Laparoscopic; D042883:Choledocholithiasis / Q000000981:diagnostic imaging* / Q000601:surgery; D006801:Humans; D007432:Intraoperative Period; D010535:Laparoscopy; D014463:Ultrasonography
keywords: Common bile duct stones; Intra-operative cholangiogram; Laparoscopic cholecystectomy; Laparoscopic ultrasound