title: Contrast-enhanced intraoperative ultrasound improves detection of liver metastases during surgery for primary colorectal cancer.
abstract: BACKGROUND
  Computed tomography (CT) is the most common staging investigation in colorectal cancer (CRC). Up to 25% of patients are found to have previously undetected hepatic lesions when intraoperative ultrasound (IOUS) of the liver is used during CRC resection. We aimed to assess the ability of IOUS to detect additional liver lesions/metastases at primary colorectal resection, and to evaluate whether contrast-enhanced IOUS (CE-IOUS) improves the detection and characterization of hepatic lesions.
  
  
  METHODS
  We performed a single-centre, prospective pilot study. At CRC resection, patients underwent IOUS of the liver. Contrast-enhanced IOUS of the liver was undertaken using i.v. sulphur hexafluoride micro-bubbles (SonoVue, 4.8 ml). Findings of CT, non-enhanced IOUS and CE-IOUS were compared. Changes in staging or management were noted. Additional lesions were corroborated with iron oxide magnetic resonance imaging (MRI).
  
  
  RESULTS
  Among 21 patients, IOUS demonstrated additional lesions in seven (33%). Contrast altered the diagnosis of non-enhanced IOUS in four (20%) and changed the management strategy in three (14%) patients. Thus, IOUS in combination with the contrast agent altered the intraoperative or postoperative management plan in four patients.
  
  
  CONCLUSIONS
  In the first study of its kind, early results suggest that the ability of IOUS to detect additional metastases is improved by CE-IOUS, and that this may impact on surgical staging and management.
authors.affiliation: Department of Hepato-Pancreato-Biliary Surgery, Bristol Royal Infirmary, Bristol, UK.
authors.forename: Ankur J
authors.initials: AJ
authors.lastname: Shah
authors.forename: Mark
authors.initials: M
authors.lastname: Callaway
authors.forename: Michael G
authors.initials: MG
authors.lastname: Thomas
authors.forename: Meg D
authors.initials: MD
authors.lastname: Finch-Jones
mesh_terms: D000230:Adenocarcinoma / Q000473:pathology / Q000556:secondary / Q000601:surgery*; D000328:Adult; D000369:Aged, 80 and over; D003110:Colonic Neoplasms / Q000473:pathology / Q000601:surgery*; D003287:Contrast Media; D005260:Female; D006801:Humans; D007430:Intraoperative Care; D008113:Liver Neoplasms / Q000000981:diagnostic imaging* / Q000556:secondary*; D008297:Male; D008875:Middle Aged; D010865:Pilot Projects; D011446:Prospective Studies; D012004:Rectal Neoplasms / Q000473:pathology / Q000601:surgery*; D013459:Sulfur Hexafluoride; D014463:Ultrasonography
chemical_list: D003287:Contrast Media; D013459:Sulfur Hexafluoride