Showing papers by "Andrea Schenk published in 2002"

Analysis of vasculature for liver surgical planning

Abstract: For liver surgical planning, the structure and morphology of the hepatic vessels and their relationship to tumors are of major interest. To achieve a fast and robust assistance with optimal quantitative and visual information, we present methods for a geometrical and structural analysis of vessel systems. Starting from the raw image data a sequence of image processing steps has to be carried out until a three-dimensional representation of the relevant anatomic and pathologic structures is generated. Based on computed tomography (CT) scans, the following steps are performed. 1) The volume data is preprocessed and the vessels are segmented. 2) The skeleton of the vessels is determined and transformed into a graph enabling a geometrical and structural shape analysis. Using this information the different intrahepatic vessel systems are identified automatically. 3) Based on the structural analysis of the branches of the portal vein, their vascular territories are approximated with different methods. These methods are compared and validated anatomically by means of corrosion casts of human livers. 4) Vessels are visualized with graphics primitives fitted to the skeleton to provide smooth visualizations without aliasing artifacts. The image analysis techniques have been evaluated in the clinical environment and have been used in more than 170 cases so far to plan interventions and transplantations.

HepaVision2 — a software assistant for preoperative planning in living-related liver transplantation and oncologic liver surgery

Abstract: HepaVision2, a user friendly software application for preoperative planning based on CT images in liver surgery is presented. It is intended for both, evaluation of potential donors in living-related liver transplantation and planning of oncologic resections. The planning takes into account the patient’s individual anatomy allowing for fully automatic calculation of individual resection proposals including volumetric analysis. The results are visualized in 3D, thus allowing the surgeon to choose the optimal strategy for each patient. The software was tested in over 50 cases by our clinical partners and our institution. Average time needed per case is below one hour, therefore allowing the use of the software application in clinical routine.

The “Virtual Institute for Computer Assistance in Clinical Radiology” (VICORA): first results of the development of algorithms and applications

Abstract: VICORA was founded in November 2000 as a non-profit institute by six major radiological centers, MeVis, and the two industrial partners Siemens Medical Solutions and MeVis Technology. The mission of VICORA is to develop algorithms and applications for computer assistance in clinical radiology, to evaluate the applications in a clinical environment and to establish them in clinical routine. Initially, VICORA focuses on the development of applications in the areas of vessel analysis, dynamic MRI, and preoperative planning.

Evaluierung von Gefäßanalyse und Volumetrie für die Planung von Leberlebendspenden

Abstract: Vor einer Leberlebendspende ist eine sorgfaltige Untersuchung des potenziellen Spenderorgans, sowie eine detaillierte Planung und Risikoabschatzung des Eingriffes notwendig. In diesem Artikel werden Methoden der Gefasanalyse und Volumetrie vorgestellt, deren Ergebnisse einen wesentlichen Einfluss auf die Spenderauswahl und Planung der Transplantation haben. Zur Evaluierung der Verfahren wurden an der Medizinischen Hochschule Hannover 29 potenzielle Spender praoperativ untersucht und die Resultate der computergestutzten Auswertung mit den intraoperativen Befunden verglichen. Sowohl die Gefasanatomie als auch die Resektatvolumina zeigten eine sehr gute Ubereinstimmung bzw. Korrelation.