Retrospective Study
Copyright ©The Author(s) 2015. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Gastroenterol. Sep 14, 2015; 21(34): 9982-9992
Published online Sep 14, 2015. doi: 10.3748/wjg.v21.i34.9982
Novel 3-dimensional virtual hepatectomy simulation combined with real-time deformation
Yukio Oshiro, Hiroaki Yano, Jun Mitani, Sangtae Kim, Jaejeong Kim, Kiyoshi Fukunaga, Nobuhiro Ohkohchi
Yukio Oshiro, Hiroaki Yano, Jun Mitani, Sangtae Kim, Jaejeong Kim, Kiyoshi Fukunaga, Nobuhiro Ohkohchi, Department of Surgery, Division of Gastroenterological and Hepatobiliary Surgery and Organ Transplantation, Faculty of Medicine, University of Tsukuba, Tsukuba 305-8575, Japan
Hiroaki Yano, Jun Mitani, Department of Computer Science, Graduate School of System Information Engineering, University of Tsukuba, Tsukuba 305-8575, Japan
Sangtae Kim, Jaejeong Kim, School of Informatics, College of Media Arts Science and Technology, Faculty of Library Information and Media Science, University of Tsukuba, Tsukuba 305-8575, Japan
Author contributions: All of the authors made substantial contributions to the acquisition, analysis, and interpretation of data and participated in writing the paper; Ohkohchi N gave final approval to the version to be published; all of the authors have read and approved the final version to be published.
Institutional review board statement: This study was approved by a research ethics committee at University of Tsukuba Hospital.
Informed consent statement: This study was conducted in accordance with the patients’ informed consent.
Conflict-of-interest statement: All authors indicated no potential conflicts of interest.
Data sharing statement: The corresponding author had full access to all the data in the study and takes responsibility for the integrity of the data and the accuracy of the data analysis.
Open-Access: This article is an open-access article which was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: http://creativecommons.org/licenses/by-nc/4.0/
Correspondence to: Nobuhiro Ohkohchi, MD, PhD, Department of Surgery, Division of Gastroenterological and Hepatobiliary Surgery and Organ Transplantation, Faculty of Medicine, University of Tsukuba, 1-1-1 Tennodai, Tsukuba 305-8575, Japan. nokochi3@md.tsukuba.ac.jp
Telephone: +81-29-8533221 Fax: +81-29-8533222
Received: March 11, 2015
Peer-review started: March 13, 2015
First decision: April 13, 2015
Revised: May 7, 2015
Accepted: July 3, 2015
Article in press: July 3, 2015
Published online: September 14, 2015
Processing time: 186 Days and 21.9 Hours
Abstract

AIM: To develop a novel 3-dimensional (3D) virtual hepatectomy simulation software, Liversim, to visualize the real-time deformation of the liver.

METHODS: We developed a novel real-time virtual hepatectomy simulation software program called Liversim. The software provides 4 basic functions: viewing 3D models from arbitrary directions, changing the colors and opacities of the models, deforming the models based on user interaction, and incising the liver parenchyma and intrahepatic vessels based on user operations. From April 2010 through 2013, 99 patients underwent virtual hepatectomies that used the conventional software program SYNAPSE VINCENT preoperatively. Between April 2012 and October 2013, 11 patients received virtual hepatectomies using the novel software program Liversim; these hepatectomies were performed both preoperatively and at the same that the actual hepatectomy was performed in an operating room. The perioperative outcomes were analyzed between the patients for whom SYNAPSE VINCENT was used and those for whom Liversim was used. Furthermore, medical students and surgical residents were asked to complete questionnaires regarding the new software.

RESULTS: There were no obvious discrepancies (i.e., the emergence of branches in the portal vein or hepatic vein or the depth and direction of the resection line) between our simulation and the actual surgery during the resection process. The median operating time was 304 min (range, 110 to 846) in the VINCENT group and 397 min (range, 232 to 497) in the Liversim group (P = 0.30). The median amount of intraoperative bleeding was 510 mL (range, 18 to 5120) in the VINCENT group and 470 mL (range, 130 to 1600) in the Liversim group (P = 0.44). The median postoperative stay was 12 d (range, 6 to 100) in the VINCENT group and 13 d (range, 9 to 21) in the Liversim group (P = 0.36). There were no significant differences in the preoperative outcomes between the two groups. Liversim was not found to be clinically inferior to SYNAPSE VINCENT. Both students and surgical residents reported that the Liversim image was almost the same as the actual hepatectomy.

CONCLUSION: Virtual hepatectomy with real-time deformation of the liver using Liversim is useful for the safe performance of hepatectomies and for surgical education.

Keywords: Liver; Surgery; Simulation; Virtual hepatectomy; Real-time deformation; Surgical education

Core tip: We aimed to develop a novel 3D virtual hepatectomy simulation software, Liversim, to visualize the real-time deformation of the liver. Eleven patients received virtual hepatectomies using Liversim; these virtual hepatectomies were performed both preoperatively and during actual surgery. The perioperative outcomes of the hepatectomies using Liversim were analyzed. There were no obvious discrepancies during the resection process between our simulation and the actual surgery. There were no significant differences in perioperative outcomes between the conventional 3D simulation software and the Liversim. Virtual hepatectomy with real-time liver deformation using Liversim is useful for the safe performance of hepatectomies.