title: Liver planning software accurately predicts postoperative liver volume and measures early regeneration.
abstract: BACKGROUND
  Postoperative or remnant liver volume (RLV) after hepatic resection is a critical predictor of perioperative outcomes. This study investigates whether the accuracy of liver surgical planning software for predicting postoperative RLV and assessing early regeneration.
  
  
  METHODS
  Patients eligible for hepatic resection were approached for participation in the study from June 2008 to 2010. All patients underwent cross-sectional imaging (CT or MRI) before and early after resection. Planned remnant liver volume (pRLV) (based on the planned resection on the preoperative scan) and postoperative actual remnant liver volume (aRLV) (determined from early postoperative scan) were measured using Scout Liver software (Pathfinder Therapeutics Inc.). Differences between pRLV and aRLV were analyzed, controlling for timing of postoperative imaging. Measured total liver volume (TLV) was compared with standard equations for calculating volume.
  
  
  RESULTS
  Sixty-six patients were enrolled in the study from June 2008 to June 2010 at 3 treatment centers. Correlation was found between pRLV and aRLV (r = 0.941; p < 0.001), which improved when timing of postoperative imaging was considered (r = 0.953; p < 0.001). Relative volume deviation from pRLV to aRLV stratified cases according to timing of postoperative imaging showed evidence of measurable regeneration beginning 5 days after surgery, with stabilization at 8 days (p < 0.01). For patients at the upper and lower extremes of liver volumes, TLV was poorly estimated using standard equations (up to 50% in some cases).
  
  
  CONCLUSIONS
  Preoperative virtual planning of future liver remnant accurately predicts postoperative volume after hepatic resection. Early postoperative liver regeneration is measureable on imaging beginning at 5 days after surgery. Measuring TLV directly from CT scans rather than calculating based on equations accounts for extremes in TLV.
authors.affiliation: Department of Biomedical Engineering, Vanderbilt University, Nashville, TN; Department of Surgery, Memorial Sloan-Kettering Cancer Center, New York, NY.
authors.forename: Amber L
authors.initials: AL
authors.lastname: Simpson
authors.affiliation: Liver Cancer Center, University of Pittsburgh Medical Center, Pittsburgh, PA.
authors.forename: David A
authors.initials: DA
authors.lastname: Geller
authors.affiliation: Department of Surgery, Center for Hepatobiliary Disease and Abdominal Transplantation, University of California San Diego, San Diego, CA.
authors.forename: Alan W
authors.initials: AW
authors.lastname: Hemming
authors.affiliation: Department of Surgery, Memorial Sloan-Kettering Cancer Center, New York, NY. Electronic address: jarnagiw@mskcc.org.
authors.forename: William R
authors.initials: WR
authors.lastname: Jarnagin
authors.affiliation: Department of Biomedical Engineering, Vanderbilt University, Nashville, TN; Pathfinder Therapeutics Inc., Nashville, TN.
authors.forename: Logan W
authors.initials: LW
authors.lastname: Clements
authors.affiliation: Department of Surgery, Memorial Sloan-Kettering Cancer Center, New York, NY.
authors.forename: Michael I
authors.initials: MI
authors.lastname: D'Angelica
authors.affiliation: Pathfinder Therapeutics Inc., Nashville, TN.
authors.forename: Prashanth
authors.initials: P
authors.lastname: Dumpuri
authors.affiliation: Department of Epidemiology and Biostatistics, Memorial Sloan-Kettering Cancer Center, New York, NY.
authors.forename: Mithat
authors.initials: M
authors.lastname: Gönen
authors.affiliation: Department of Surgery, University of Florida, Gainesville, FL.
authors.forename: Ivan
authors.initials: I
authors.lastname: Zendejas
authors.affiliation: Department of Biomedical Engineering, Vanderbilt University, Nashville, TN.
authors.forename: Michael I
authors.initials: MI
authors.lastname: Miga
authors.affiliation: Pathfinder Therapeutics Inc., Nashville, TN.
authors.forename: James D
authors.initials: JD
authors.lastname: Stefansic
mesh_terms: D000328:Adult; D000368:Aged; D005260:Female; D006498:Hepatectomy / Q000379:methods*; D006801:Humans; D008113:Liver Neoplasms / Q000601:surgery*; D008115:Liver Regeneration; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D012984:Software; D025321:Surgery, Computer-Assisted; D014057:Tomography, X-Ray Computed; D016896:Treatment Outcome