title: Accuracy of preoperative automatic measurement of the liver volume by CT-scan combined to a 3D virtual surgical planning software (3DVSP).
abstract: BACKGROUND
  Liver volumetry is a critical component of safe hepatic surgery, in order to minimize the risk of postoperative liver failure. Liver volumes can be calculated routinely using the time-consuming gold standard method of manual volumetry. The current work sought to evaluate an alternative automatic technique based on a novel 3D virtual planning software, and to compare it to the manual technique.
  
  
  METHODS
  A prospective study of patients undergoing liver resection was conducted. Every patient had a pre and 2-day postoperative CT-scan. For each patient, total, remnant and resected volumes were calculated manually and automatically. Planes of resection were verified by a hepatobiliary surgeon and compared with postoperative volumes. Paired t-tests and correlation coefficients were calculated.
  
  
  RESULTS
  A major hepatectomy was carried out in 36/43 patients. The automatic TLV (1,759 mL) and the manual TLV (1,832 mL) were significantly different (p < 0.001), but extremely highly correlated (r = 0.989). The percentages of preoperative RLV (manual 58.5%, automatic 58.9%) were similar, with an excellent correlation of 0.917. The preoperative RLV were matched with the 2-day postoperative RLV showing a significant difference (p = 0.0301). The resected volumes using both techniques (871 and 832 mL) were compared with the resected specimen volume (670 mL), showing a significant difference (p < 0.001) but a high degree of correlation (r = 0.874).
  
  
  CONCLUSIONS
  The 3D virtual surgical planning software is accurate and reliable in determining the total liver and future remnant liver volumes. This technique demonstrates a good correlation with the manual technique. Future work will be required to confirm these findings and to evaluate the clinical value of the three-dimensional planning platform.
authors.affiliation: HPB Surgery & Liver Transplantation Unit, CHUM St-Luc, University of Montreal, 1058 Saint-Denis, Room 6303B, Montreal, QC, H2X 3J4, Canada.
authors.forename: André
authors.initials: A
authors.lastname: Bégin
authors.forename: Guillaume
authors.initials: G
authors.lastname: Martel
authors.forename: Réal
authors.initials: R
authors.lastname: Lapointe
authors.forename: Assia
authors.initials: A
authors.lastname: Belblidia
authors.forename: Luigi
authors.initials: L
authors.lastname: Lepanto
authors.forename: Luc
authors.initials: L
authors.lastname: Soler
authors.forename: Didier
authors.initials: D
authors.lastname: Mutter
authors.forename: Jacques
authors.initials: J
authors.lastname: Marescaux
authors.forename: Franck
authors.initials: F
authors.lastname: Vandenbroucke-Menu
mesh_terms: D000328:Adult; D000368:Aged; D005260:Female; D005500:Follow-Up Studies; D006498:Hepatectomy / Q000379:methods*; D006801:Humans; D021621:Imaging, Three-Dimensional / Q000379:methods*; D008099:Liver / Q000000981:diagnostic imaging* / Q000601:surgery; D008113:Liver Neoplasms / Q000000981:diagnostic imaging / Q000556:secondary / Q000601:surgery; D008297:Male; D008875:Middle Aged; D057234:Preoperative Period; D011446:Prospective Studies; D015203:Reproducibility of Results; D012984:Software; D025321:Surgery, Computer-Assisted / Q000379:methods*; D014057:Tomography, X-Ray Computed / Q000379:methods*; D014584:User-Computer Interface; D055815:Young Adult