Arno Krüger

Interactive visualization for neck-dissection planning

In this paper, we present visualization techniques for neck dissection planning. These interventions are carried out to remove lymph node metastasis in the neck region. 3d visualization is intended to explore and to quantify anatomic and pathologic structures and thus support decisions concerning the surgical strategy. For this purpose we developed and combined visualization and interaction techniques such as cutaway views, silhouettes and colorcoded distances. In addition, a standardized procedure for processing and visualization of the patient data is presented.

Sinus Endoscopy - Application of Advanced GPU Volume Rendering for Virtual Endoscopy

For difficult cases in endoscopic sinus surgery, a careful planning of the intervention is necessary. Due to the reduced field of view during the intervention, the surgeons have less information about the surrounding structures in the working area compared to open surgery. Virtual endoscopy enables the visualization of the operating field and additional information, such as risk structures (e.g., optical nerve and skull base) and target structures to be removed (e.g., mucosal swelling). The Sinus Endoscopy system provides the functional range of a virtual endoscopic system with special focus on a realistic representation. Furthermore, by using direct volume rendering, we avoid time-consuming segmentation steps for the use of individual patient datasets. However, the image quality of the endoscopic view can be adjusted in a way that a standard computer with a modern standard graphics card achieves interactive frame rates with low CPU utilization. Thereby, characteristics of the endoscopic view are systematically used for the optimization of the volume rendering speed. The system design was based on a careful analysis of the endoscopic sinus surgery and the resulting needs for computer support. As a small standalone application it can be instantly used for surgical planning and patient education. First results of a clinical evaluation with ENT surgeons were employed to fine-tune the user interface, in particular to reduce the number of controls by using appropriate default values wherever possible. The system was used for preoperative planning in 102 cases, provides useful information for intervention planning (e.g., anatomic variations of the Rec. Frontalis), and closely resembles the intraoperative situation.

Advanced GPU Volume Rendering for Virtual Endoscopy

For difficult cases in endoscopic sinus surgery, a careful planning of the intervention is necessary. Virtual endoscopy enables the visualization of the operating field and additional information, such as risk structures and target structures to be removed. The Sinus Endoscopy system provides the functional range of a virtual endoscopic system with special focus on a realistic representation. Furthermore, by using direct volume rendering, we avoid time-consuming segmentation steps for the use of individual patient datasets. However, the image quality of the endoscopic view can be adjusted in a way that a standard computer with a modern standard graphics card achieves interactive frame rates with low CPU utilization. Thereby, characteristics of the endoscopic view are systematically used for the optimization of the volume rendering speed. As a small standalone application it can be instantly used for surgical planning and patient education. The system was used for preoperative planning in 102 cases, provides useful information for intervention planning (e.g., anatomic variations of the Rec. Frontalis), and closely resembles the intraoperative situation.

Haptische Interaktion zur Planung von Nasennebenhöhlen-Operationen

Moderne Operationstechniken im Bereich der Nasennebenhohlen bringen Vorteile fur den Patienten, jedoch auch neue Herausforderungen fur den Operateur mit sich. Durch die endoskopischen Verfahren ist die Navigation und Orientierung wahrend des Eingriffs erschwert und setzt eine besonders grundliche Planung voraus. Bei Problemfallen ist die Nutzung von 2d-Schichtbildern, die traditionell Verwendung finden, schwieriger. Vor allem bei Rezidivoperationen fehlen oft zur Orientierung wichtige anatomische Landmarken. In diesem Paper wird ein System vorgestellt, das mit Hilfe virtueller Endoskopie eine patientenindividuelle Planung von endoskopischen Nasennebenhohlen-Eingriffen unterstutzt. Dabei wird besonderer Wert auf die Interaktion mit der 3d-Darstellung und eine intuitive Nutzerfuhrung gelegt.