Cluster Computing:

IMMERSIVE VISUALIZATION HELPS RESEARCHERS UNDERSTAND DATA

A large-scale immersive display system is helping university and industry researchers at the University of Hull in the U.K. gain deeper understanding of highly complex data. The ability to view and manipulate three-dimensional models and simulations in an immersive, volumetric space is enhancing communications and improving collaboration among research teams. And, in the recent project described below, the system helped the staff at an area medical center demonstrate how 3D visualization can improve the planning and administration of radiation treatment for cancer patients.

The Facility

Funded by the Strategic Research Investment Funding (SRIF) initiative of the Higher Education Funding Council for England (HEFCE), the Hull Immersive Visualization Environment (HIVE) Centre provides state-of-the-art equipment, expertise and technologies for work with visualization, human interaction, and high-performance computing. Staffed by teams with specialization in advanced visualization and related fields, the HIVE Centre assists researchers developing applications across a broad range of scientific study. The facility includes a 72 CPU high-performance computing cluster, Visualization Auditorium, Visualization Technology Laboratory and a Research Laboratory. The centerpiece of the facility, the Visualization Auditorium, features a PowerWall from Fakespace Systems, which was purchased through Antycip SA, a value-added reseller based in Oxfordshire, UK. This is a three-by-five meter (10-ft x 16-ft) flat wall solution that enables viewing of large-scale stereoscopic models and simulations.

Immersive Visualization

When viewed with special active shutter glasses, applications running on the PowerWall appear in three-dimensional space. The auditorium is designed to support group immersive interaction. It seats up to 40 people for multimedia presentations that include stereo visualization. The auditorium stage has a motion-tracking system, so that the viewpoint of the system provides realistic motion parallax. As the primary "user" in a simulation changes position, the viewpoint of the application on the PowerWall changes, enhancing the immersive experience.

Ongoing work at the HIVE Centre includes: biomedical simulation and visualization, scientific visualization in chemistry and geography, archeological visualization, immersive visualization for diagnosis and treatment in medicine, sports performance assessment, and virtual prototyping and design optimization in engineering.

Radiotherapy Treatment of Cancer

In a recent collaboration with a regional medical organization, researchers created a simulation of an actual radiotherapy unit of a local hospital (Princes Royal Hospital, Hull). The simulation was intended to illustrate how planning in 3D benefits state-of-the-art radiation treatment, by improving the way radiation treatments are targeted to follow tumor geometry and avoid undue exposure of, close lying, healthy organs.

The hospital uses a Linear Accelerator to deliver x-ray beams that allow customized radiation treatment to each patient using a technique known as Intensity Modulated Radiotherapy (IMRT). This technique is state of the art and has only been adopted by a handful of hospitals in the world so far. The x-ray beam of the accelerator is shaped to conform to the shape of tumor using a computer controlled multi-leaf collimator, which is a special kind of shutter system that shapes the radiation beam. Furthermore, the intensity of a beam is customized so that the superposition of several such beams, applied from different directions, creates the most ideal dose distribution for each patient. The researchers programmed a geometrically accurate computer model of the accelerator for use in the simulation. The simulator loads treatment plan information and the Computerized Tomography (CT) scan data of an actual patient’s tumor to create a virtual environment simulation for a patient’s course of treatment. Using the Fakespace PowerWall, all of this data is displayed in realistic 3D imagery, providing an immersive view of the tumor and the radiation beams (which are normally invisible) used to treat the cancer.

The initial aim of this research project was simply as a demonstration for the general public to provide a better understanding of how radiation therapy works. Hospital personnel were so impressed by the virtual environment simulations that work is now underway to further develop the simulation as a tool for training radiotherapists. Furthermore a study is being planned to determine the benefits of immersive visualization for creating and reviewing radiation treatment plans.