Julius—A Software Framework for Medical Visualization E. Keeve N. Hanssen, T. Jansen*, Z. Krol, M. Lievin, B. von Rymon-Lipinski*, K. Raic, L. Ritter
Ergonomics in Communications 2_3_4 Computer Aided Surgery Surgical Systems Laboratory
Computer aided surgery deals with patient-specific information from Computer Tomography (CT), Magnetic Resonance Imaging (MRI) and other medical scans. One major challenge is to bring the various facets of medical visualization together into one single environment, which is required for seamless integration of pre-operative and intra-operative data. Therefore we develop the medical software framework ‘Julius’.
Cross-links:
It offers easy incorporation of advanced algorithms and techniques of image guided
Computer Aided Surgery
surgery, including visualization, surgical simulation and navigation. The framework architecture is based on three conceptual layers as shown in Fig. 1. Add-Ins File
View
...
JuliusObject Communication System (JOCS)
Julius Software Development Kit (JSDK) Data
Msg
...
Modules
Our software framework is implemented on top of the Qt Library, using functionality to build up a user-friendly graphical user interface and basic object-oriented tools. The default implementation of the hardware-accelerated visualization uses the Visualization Toolkit VTK in combination with the low-level OpenGL application-programming interface. Since the two software libraries on which Julius is build on are public-domain, no royalties have to be rewarded to third-parties. For best portability and scalability Julius is independent of the underlying hardware and operating system. As a result, it runs on both high-end UNIX workstations and low-cost desktop PCs.
Figure 2: The images show a simple medical processing pipeline, including data import, segmentation and mesh generation. The corresponding algorithms are encapsulated in plugins and can be controlled intuitively through the JGUI (CT image data courtesy of R. Kikinis, Harvard Medical School, Boston, MA).
Keywords: rapid application development, medical imaging, real-time image processing and visualization, image guided surgery *Contact:
[email protected];
[email protected]
C++GUI Toolkit (Qt)
Julius Qt Widgets
Julius Visual Layer (JVL)
Figure 1: The three conceptual layers of the software framework. The Julius Software Development Kit (JSDK) builds the core application and controls the medical data and message processing. The Julius Graphical User Interface acts like a front-end to the JSDK and offers easy handling combined with time saving functionality. The Julius Object Communication System (JOCS) provides information exchange schemes and communication interfaces.
Visualization Tollkit (VTK)
Julius Graphical Interface (JGUT)
Julius—A Software Framework for Medical Visualization
Over the last year Julius has become one main part of the research activities of our group. Several project results were successfully integrated as plug-ins into the framework. Examples are image segmentation, registration and navigation techniques together with advanced visualization algorithms. Additional tools, such as the anatomy browser, facilitate Cooperations:
the composition of individual plug-ins to create a typical medical workflow.
Surgical Planning Laboratory, Harvard Medical School, Boston, MA Cranio- and Maxillofacial Surgery, TU München
Figure 3: Screenshot of the Julius front-end. The main view for visualization (center) shows a segmented 3D knee model together with an overlay image of the transversal slice. The slice views (right column) show the corresponding 2D visualization of the volume dataset. The step-card (left) shows a complete hierarchical view of anatomical structures (CT image data courtesy of R. Kikinis, Harvard Medical School, Boston, MA).
With Julius we develop a powerful, intuitive and extendible software framework for computer aided surgery. The modular concept enables easy incorporation of research results from external projects and clinical partners. Application areas range from cranioand maxillofacial surgery to neurosurgery and orthopedics.
Figure 4: Advanced visualization techniques can be implemented with the Julius renderer plug-ins. Different renderers can be combined in one view at run-time. The image shows 3D surface rendering in combination with multiple cut planes (CT image data courtesy of H.-F. Zeilhofer, TU München).
Reference: Keeve, E.; Jansen T.; Krol Z.; Ritter L.; von Rymon-Lipinski B.; Sader R.; Zeilhofer H.-F.; Zerfass P. : Julius—An Extendable Software Framework for Surgical Planning and ImageGuided Navigation, Proceedings Fourth International Conference on Medical Image Computing and Computer-Assisted Intervention MICCAI’01, Utrecht, October 14–17, 2001.
