ERCIM News is a quarterly publication from the European Research Consortium for Informatics and Mathematics. The theme of the latest issue is "Grids: The Next Generation." It contains 32 papers, all available online, covering the following aspects of grid computing: infrastructure, architecture, middleware, programming, applications and new projects. One of the most interesting applications is "Virtual Vascular Surgery on the Grid." The University of Amsterdam recently demonstrated a virtual bypass operation involving grid services for storage, large-scale simulation and visualization. The whole process used computers and visualization services in the Netherlands, Poland, Spain and Austria. Read more on this fascinating development.
Here is the introduction to the paper itself.
Medical simulations and visualizations typically require computational power not usually available in a hospital. The University of Amsterdam recently demonstrated Virtual Vascular Surgery (a virtual bypass operation), where large-scale simulation and visualization capabilities were offered as services on the Grid.
And here is the description of the problem and the solution found by the researchers.
Arteriosclerosis is a widespread disease that manifests particularly in developed countries. Treatment often involves surgery, such as the placement of bypasses that lead the blood around clogged arteries to restore normal blood flow. A surgeon plans these interventions on the basis of 3D images obtained from MRI or CT scans. Apart from considerations such as accessibility, the attainable improvement in the blood flow will determine what type of treatment is appropriate. Improvements in the support for planning these procedures are expected to improve their success rate.
We have developed a prototype grid-based system for virtual vascular surgery, which may be used during pre-operative planning or as a valuable tool in the training of novice vascular surgeons. The prototype uses advanced distributed simulations and visualizations to support vascular surgeons in making pre-operative decisions.
The hedge [of hawthorns] formed a type of suite of chapels disappearing under the wall of their flowers heaped as on an altar; under them, the sun placed on the ground a grid of light, as if it had come through a glass window; their fragrance was as smooth and as clearly defined in its form as if I had stood before the Virgin’s altar, and the flowers, so ornamented, each distractedly held its dazzling bouquet of stamens, fine and shining ribs of flamboyant style like those which in the church line the ramp of the rood-screen or the mullions of stained-glass windows and which bloomed into the white flesh of strawberry blossoms.
—Marcel Proust (1871–1922)
The figure below shows the different steps from this distributed image-based blood-flow simulation and visualization on the grid (Credit: Peter Sloot and Alfons Hoekstra, University of Amsterdam).
From top left to bottom right: A patient is scanned in Leiden, The Netherlands; this results in a raw image stored in a Storage Element on the Grid (eg Poznan, Poland); this is segmented, filtered and cropped, using a Grid service; a bypass is added; a computational mesh is generated (on the local machine) and given to the parallel flow solver, running on Compute Elements in the Grid (Amsterdam and Spain); the resulting flow fields are displayed on the local machine using visualization services offered by the Grid Visualization Kernel (Linz, Austria).
Of course, managing sensitive medical information on the web requires strict data security. So a special middleware layer was developed in what is called the CrossGrid project.
The CrossGrid project is oriented towards compute- and data-intensive applications characterized by the interaction with a person in the loop. The CrossGrid pan-European distributed testbed shares resources across sixteen European sites. One key component of Crossgrid is the Migrating Desktop (MD) grid portal. The MD produces a transparent user work environment, permitting the user to access grid resources from remote computers. Users can run applications, manage data files, and store personal settings independently of the location or the terminal type.
The paper offers more details about the process which will be demonstrated in real time during the upcoming European Grid Conference in Amsterdam, February 2005 (EGC2005).
For more information, here is a link to other medical applications of the CrossGrid project.
Sources: Peter Sloot and Alfons Hoekstra, University of Amsterdam, for ERCIM News No. 59, October 2004
Related stories can be found in the following categories.
Grid Computing
Medicine
Virtual Reality
Vision and Visualization.