Holger Bourquain

Fraunhofer Institute for Medical Image Computing MEVIS, Bremen, Bremen, Germany

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Publications (46)46.46 Total impact

  • [Show abstract] [Hide abstract]
    ABSTRACT: The implementation of intraoperative navigation in liver surgery is handicapped by intraoperative organ shift, tissue deformation, the absence of external landmarks, and anatomical differences in the vascular tree. To investigate the impact of surgical manipulation on the liver surface and intrahepatic structures, we conducted a prospective clinical trial. Eleven consecutive patients [4 female and 7 male, median age = 67 years (range = 54-80)] with malignant liver disease [colorectal metastasis (n = 9) and hepatocellular cancer (n = 2)] underwent hepatic resection. Pre- and intraoperatively, all patients were studied by CT-based 3D imaging and assessed for the potential value of computer-assisted planning. The degree of liver deformation was demonstrated by comparing pre- and intraoperative imaging. Intraoperative CT imaging was successful in all patients. We found significant deformation of the liver. The deformation of the segmental structures is reflected by the observed variation of the displacements. There is no rigid alignment of the pre- and intraoperative organ positions due to overall deflection of the liver. Locally, a rigid alignment of the anatomical structure can be achieved with less than 0.5 cm discrepancy relative to a segmental unit of the liver. Changes in total liver volume range from -13 to +24%, with an average absolute difference of 7%. These findings are fundamental for further development and optimization of intraoperative navigation in liver surgery. In particular, these data will play an important role in developing automation of intraoperative continuous registration. This automation compensates for liver shift during surgery and permits real-time 3D visualization of navigation imaging.
    World Journal of Surgery 04/2010; 34(8):1887-93. · 2.23 Impact Factor
  • Fraunhofer MEVIS. 01/2010;
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    ABSTRACT: Virtual imaging procedures have only rarely been analyzed in pediatric populations. We evaluated the role of CT-based virtual surgery planning in pediatric patients experiencing hepatic vascular malformations (HVM). We analyzed 12 children with complex hepatic vascular malformations. All of the children received multislice CT scans with contrast medium followed by virtual 3-dimensional reconstructions using the software assistants MeVis LiverAnalyzer and MeVis LiverExplorer. The impact on treatment planning and the correspondence to clinical findings was assessed. Highest accuracies of virtual data were found in cases of intrahepatic portocaval shunt and persistent ductus venosus. Here, virtual data revealed congenital vascular conditions, which were not always seen using standard imaging diagnostics. In some patients with portalvenous thrombosis, virtual imaging provided important contributions to determining the feasibility of different shunt procedures. However, in some patients experiencing portalvenous thrombosis or liver diffuse hemangioma, virtual methods were not as accurate as standard diagnostic procedures. Nevertheless, these tools facilitated simultaneous and continuous illustrations of the different vascular systems. Virtual imaging and planning procedures had an important impact on treatment strategies and outcomes in children with HVM. Their use as standard diagnostic tools in selected cases of HVM should be considered.
    Journal of pediatric gastroenterology and nutrition 10/2009; 50(1):67-73. · 2.18 Impact Factor
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    ABSTRACT: Although the consequences of partial venous outflow interruption have attracted only limited attention in liver surgery, maximal preservation of liver function after hepatic resection requires preservation of circulation in the remnant liver, especially hepatic vein drainage. Data from 30 patients undergoing 3-dimensional imaging were analyzed to clarify the relationship between the area of the ventral right anterior section (RAS) and that drained by regional hepatic vein tributaries. The feasibility of our preliminary technique of right hemihepatectomy preserving the ventral RAS also was evaluated. The median estimated volume of the ventral RAS was 230 mL (range, 88-391). The average ratio of this estimated volume of the ventral RAS to total estimated liver volume was 18.0 +/- 4.9%. The median volume of the territory served by middle hepatic vein (MHV) tributaries draining the ventral RAS, expressed as a percentage of the whole volume of the ventral RAS, was 82.5%. Findings in fusion images of portal and hepatic vein territories demonstrated an area of MHV tributaries comparable with the ventral RAS area in 73.3% of all cases. As for the results of right hemihepatectomy with the ventral RAS preserved, no tumor was exposed on transection surfaces, and no recurrence took place within the preserved ventral RAS of the remnant liver. Procedures considering the importance of regional venous drainage offer the possibility of reducing the extent of surgery without loss of effectiveness.
    Surgery 08/2009; 147(3):450-8. · 3.37 Impact Factor
  • J Harms, H Bourquain, A Schenk, T Kahn, J Fangmann
    Zeitschrift Fur Gastroenterologie - Z GASTROENTEROL. 01/2009; 47(06).
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    ABSTRACT: Computational support in intervention planning promises to support the subjective interpretation of data with reproducible measurements. Moreover, it is possible to develop and apply models that provide additional information which is not directly visible in the data. Based on computertomography multi-slice images of the liver, the planning software developed by MeVis Research offers tools to evaluate different interventional strategies preoperatively. In identifying patient individual risks, an optimized interventional plan is developed. In radiofrequency ablation of liver tumors, the treatment success highly depends on an effective placement of the radiofrequency applicators into the tumor to achieve sufficient coagulative necrosis. Beside tumor size and shape, the cooling effects of surrounding vessels are taken into account for a numerical estimation of the accessible thermal destruction. Based on this information, an optimized positioning can be obtained. In case of the surgical resection, removing the tumor together with a safety margin from the liver, requires transsection of local vascular structures that are supplying or draining a dedicated liver region. The identification and quantitative assessment of these regions, which are functionally endangered, guides the preoperative evaluation of surgical strategies. Subsequently proper visualizations of the planning data help to identify critical structures, and allow for a better control of the intraoperative situation. The planning data are matched with images from intraoperative ultrasound, and the aligned data are displayed in the operating theatre on monitors, which are placed directly the table. Moreover, an intraoperative adaption of the surgical planning is addressed: In oncologic liver surgery, additional tumors that were not visible in the preoperative images are often found during the intervention. With such findings, the resection strategy must be updated or completely revised. The planning software allows for an automated adaption of the surgical planning. The aim is to provide surgeons with an efficient tool for the quantitative assessment of planning, which is integrated in the workflow of oncologic liver interventions. To provide a meaningful procedural support of the surgical workflow, the cognitive needs of the surgeons have to be taken into account.
    12/2008: pages 114-117;
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    ABSTRACT: The ability to acquire and store radiological images digitally has made this data available to mathematical and scientific methods. With the step from subjective interpretation to reproducible measurements and knowledge, it is also possible to develop and apply models that give additional information which is not directly visible in the data. In this context, it is important to know the characteristics and limitations of each model. Four characteristics assure the clinical relevance of models for computer-assisted diagnosis and therapy: ability of patient individual adaptation, treatment of errors and uncertainty, dynamic behavior, and in-depth evaluation. We demonstrate the development and clinical application of a model in the context of liver surgery. Here, a model for intrahepatic vascular structures is combined with individual, but in the degree of vascular details limited anatomical information from radiological images. As a result, the model allows for a dedicated risk analysis and preoperative planning of oncologic resections as well as for living donor liver transplantations. The clinical relevance of the method was approved in several evaluation studies of our medical partners and more than 2900 complex surgical cases have been analyzed since 2002.
    Proc SPIE 04/2008;
  • Pneumologie 01/2008; 62.
  • Rofo-fortschritte Auf Dem Gebiet Der Rontgenstrahlen Und Der Bildgebenden Verfahren - ROFO-FORTSCHR RONTGENSTRAHL. 01/2008; 180.
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    ABSTRACT: Multiple imaging approaches are currently used for diagnosis and surgery planning of hepatobiliary tumors and living donor liver transplantations. Conventional imaging studies remain insufficient to demonstrate the individual anatomy. Refinements in CT technology with the introduction of “multidetector-row” CT scanners and implementation of mathematical methods on computerized digital data enabled CT based 3D- visualizations. This renders preoperative surgery planning more reliable and reproducible. Since the application in oncological liver surgery has been studied previously, our interest focussed on pancreatic- and biliary tract tumors including preoperative work-up in living donor liver transplantation. A total of 29 patients were assessed. CT based 3D- display provided accurate preoperative visualization and computerized risk analyses for safety margins of pancreatic- and biliary- tract tumors. In living related liver transplantation the 3D- procedure may help to recognize vascular variants and to define the splitting line. The results may have major impact on patient selection and in our opinion allow better planning of the appropriate surgical approach.
    12/2007: pages 512-515;
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    ABSTRACT: Complex, highly variable, anatomic relationships in the portal hilum complicate the surgical management at hilar cholangiocarcinoma. Preoperative three-dimensional (3D) imaging to stage the tumor and define anatomy may help in planning for curative resection. Between 2003 and 2006, 20 consecutive patients with hilar cholangiocarcinoma underwent preoperative multidetector row computed tomography (MDCT) cholangiography; 3D images of the portal vein, hepatic artery, and bile ducts were created and viewed simultaneously. Longitudinal tumor extension was evaluated by direct cholangiography and 3D cholangiography, and contiguous spread by 2D computed tomography (CT). Of 20 patients, 15 underwent surgical resection. Liver resection was planned based on 3D imaging that allowed visualization of the relationship between the tumor and the umbilical portion of the left portal vein, or the bifurcation of the anterior and posterior branch of the right portal vein. Preoperative and operative findings were compared. All patients tolerated 3D CT without serious complication. The accuracy rates of longitudinal tumor extension, using the Bismuth-Corlette classification system, were 85% (11/13) and 87% (13/15) with direct cholangiography and 3D cholangiography, respectively. The sensitivity, specificity, and accuracy rates were 100%, 80%, and 87% for portal invasion and 75%, 91%, and 87% for hepatic arterial invasion. The number of bile duct orifices in the cut end of the hilar plate was estimated correctly in 13 of 15 patients. There were no operative deaths. Potentially curative resection was achieved in 14 of 15 patients. 3D images provide accurate information about the relationship between hilar cholangiocarcinoma and adjacent vessels. This technique is a powerful new tool for improving the proportion of potentially curative resection.
    Surgery 12/2007; 142(5):666-75. · 3.37 Impact Factor
  • Journal of the American College of Surgeons 11/2007; 205(4):626-7. · 4.50 Impact Factor
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    ABSTRACT: Recent developments in image-based computer assistance provide an improved visualisation of the intrahepatic vascular branching system in a virtual three-dimensional model of the liver, allowing a quantitative assessment of any vascular territory. The advantages of computer-assisted resection planning refer to a better preoperative assessment of functional resectability in areas at risk for either devascularisation or impaired drainage. In selected cases, this information may have a considerable influence on operative planning, especially with regard to the extent of resection or the need for vascular reconstruction. Due to the great anatomical variability of the intrahepatic branching patterns of the right liver lobe, this seems to be particularly important in extended left hepatectomies or in repeat hepatectomy when intrahepatic vascular anatomy may be altered. The development of navigation techniques to ensure the accurate application of the preoperative planned resection line is under investigation but not available yet.
    Zeitschrift für Gastroenterologie 10/2007; 45(9):965-70. · 1.41 Impact Factor
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    ABSTRACT: A major concern in adult-to-adult living donor liver transplantation is the selection of graft type; that is, is it is better to use the right lobe with or without the middle hepatic vein (MHV)? This choice has a considerable impact on donor safety, vascular reconstruction and graft function in the recipient. To facilitate making an appropriate choice, on the basis of a preliminary study (n = 17), we herein propose a graft selection algorithm using three parameters: graft-to-recipient body weight ratio (GRWR), percentage remnant liver volume (%RLV) and estimated congestion ratio (ECR). The algorithm was evaluated with 50 consecutive cases with respect to postoperative liver function of donors and recipients and survival of recipients. Postoperative recovery was comparable between the two groups (p = NS). The overall cumulative 18-month survival rate was 86.7% for the 'with MHV graft group', and 76.1% for the gwithout MHV graft grouph (p = NS). For 41 cases (82%), graft types were chosen according to the algorithm, whereas the remaining 9 cases (18%) needed detailed discussion of donor, recipient and operative factors. In conclusion, we constructed a graft selection algorithm based on congestion volume, which will contribute to objective graft-type selection in adult-to-adult LDLT.
    American Journal of Transplantation 08/2007; 7(7):1788-96. · 6.19 Impact Factor
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    ABSTRACT: Accurate knowledge of partial anatomy is essential in hepatic surgery but is difficult to acquire. We describe the potential impact of a new technique for constructing three-dimensional virtual images of the portal vein, hepatic artery, and bile ducts and present a representative case. An 80-year-old man was suspected of having papillary cholangiocarcinoma arising in S8 of the liver and extending to the hepatic hilum intraluminaly. Right hemihepatectomy with bile duct resection was planned. However, it was uncertain whether duct-to-duct biliary reconstruction would be possible based on the appearance of the confluence of the right and left hepatic ducts on cholangiogram and conventional computed tomograph. Virtual three-dimensional images of the liver were constructed and revealed vascular and biliary anatomy. They showed that the upper margin of bile duct excision would be 19 mm from the umbilical point of the left portal vein, and that the site of the left branch of the caudate lobe bile duct could be preserved. Based on this information, we performed a sphincter-preserving biliary operation safely without complications. Planning complex biliary surgery may be improved by the use of virtual three-dimensional images of the liver. This approach is especially useful in candidates for postoperative regional chemotherapy.
    Journal of Gastrointestinal Surgery 06/2007; 11(5):666-70. · 2.36 Impact Factor
  • Rofo-fortschritte Auf Dem Gebiet Der Rontgenstrahlen Und Der Bildgebenden Verfahren - ROFO-FORTSCHR RONTGENSTRAHL. 01/2007; 179.
  • Zeitschrift Fur Gastroenterologie - Z GASTROENTEROL. 01/2007; 45(9):965-970.
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    K J Oldhafer, H Bourquain, G A Stavrou
    Zentralblatt für Chirurgie 05/2006; 131(2):W22-33; W34-5. · 0.69 Impact Factor
  • Christoph Wald, Holger Bourquain
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    ABSTRACT: The combination of modern scanner technology with advanced image postprocessing allows for high-fidelity three-dimensional imaging of pertinent patient anatomy. Currently available solutions provide not only precise qualitative but also advanced quantitative imaging, resulting in precise estimates of whole or partial organ or tumor volumes. Simulations of open surgical or percutaneous interventions are an important application of advanced image analysis. Image postprocessing may be performed locally or remotely using readily available Internet connectivity. Results can be offered to the treating physician in a very realistic format and can be made available in an interactive fashion, such as in the operating room. Clinically appropriate use of this powerful technology can alter the surgical approach to individual patients’ problems, help with preoperative feasibility and risk assessment, and ultimately may result in shorter and safer procedures.
    Journal of Gastrointestinal Surgery 03/2006; 10(2):161-5. · 2.36 Impact Factor
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    ABSTRACT: Preoperative risk assessment for image based surgery planning often re- quires considerable technical and personnel resources especially for certain comple x interventions, such as live rs urgery .T he purpose of the project SIMPL wa st oe stablish ar emote service for specialized tasks in medical image analysis and the visualization of results. In this context we developed aw eb-based system to support the service pro- cess. Requirements included an adaption to the existing clinical infrastructure, time constraints, and quality management support. The software design is based on ap ro- cess modelling concept and modern web technologies are used for an implementation that fulfills the demands regarding security and independence of special software. The prototypical system has been tested during the SIMPL project with international clin- ical partners and is no wu sed in optimized form on ar egular basis.
    Informatik 2006 - Informatik für Menschen, Band 1, Beiträge der 36. Jahrestagung der Gesellschaft für Informatik e.V. (GI), 2.-6. Oktober 2006 in Dresden; 01/2006

Publication Stats

393 Citations
46.46 Total Impact Points

Institutions

  • 2008–2010
    • Fraunhofer Institute for Medical Image Computing MEVIS
      Bremen, Bremen, Germany
  • 2009
    • University of Tuebingen
      • Department of Paediatric Surgery
      Tübingen, Baden-Württemberg, Germany
  • 2007–2009
    • Yokohama City University
      Yokohama, Kanagawa, Japan
    • University of Duisburg-Essen
      Essen, North Rhine-Westphalia, Germany
  • 2006
    • Deutsche Gesellschaft für Allgemein- und Viszeralchirurgie
      Celle, Lower Saxony, Germany
    • Lahey Hospital and Medical Center
      • Department of Radiology
      Burlington, MA, United States
  • 2005
    • MeVis Medical Solutions AG
      Bremen, Bremen, Germany
    • University of Leipzig
      Leipzig, Saxony, Germany
    • Universitätsklinikum Tübingen
      Tübingen, Baden-Württemberg, Germany
  • 2004
    • Universität Bremen
      Bremen, Bremen, Germany
  • 2003
    • Philipps-Universität Marburg
      • Klinik für Strahlendiagnostik (Marburg)
      Marburg an der Lahn, Hesse, Germany