e-Learning

Virtual MRI

Virtual Magnetic Resonance Imager

A realistic simulation of a MRI was developed. For the user it should be possible to change all relevant setting of the virtual scanner and to adapt them to the expected pathology. Students and doctors in training are the target group.

Screenshot of the Virtual MRI

At the moment the pulse sequence classes SR, IR, SE, TSE, FLASH and FISP are implemented. By a plugin mechanism this list can be easily extended. Parameters, like TR, TE, TI, flip-angle or echo train length, can be adjusted. The choice of matrix size, FOV, slice-thickness and number of acquisitions affect the signal-to-noise ratio of the images. In a first step, the simulation calculates the signal intensity in the k-space. Aliasing- and motion-artifacts are simulated by modifying the k-space data. In a last step, a 2D-fouriertransform of the k-space data is performed. Window and center of the resulting images can be changed. The simulation time can be optionally delayed till the real measuring time. The algorithms of the simulation are based on parameter-images of the three physical basic items T1, T2 and proton density. They are calculated once from a patient examination with suitable pulse sequences. To work out pathologies a small graphic tool is included. The graphical user interface is oriented on a real MR scanner. The software is implemented in pure Java under the GPL license.

On a 500 MHz PC the software calculates an image in 5 to 20 seconds, depending on the pulse sequence and the degree of the desired artifacts.

An interactive simulation of a real world examination is possible on a standard PC. The users can study the operation of a costly and not everywhere available equipment on their desktop.

RSNA 2002

The current version of the simulation was presented at the RSNA 2002, 88th Scientific Assembly and Annual Meeting, Chicago, IL, USA. During the meeting a lecture was given. The presentation was given the RSNA infoRAD award cum laude.

Picture of the booth at the RSNA 2002  infoRAD

Project Team

Concept:
Thomas Hacklaender, MD, PhD (hacklaender@iftm.de)

Programming:
Christian Schalla
Andreas Truemper
Thomas Hacklaender, MD, PhD

Localization:
English version, Heinrich Mertens, PhD
Estonian version, Katri Hackländer, MD

Documentation:
English version, Heinrich Mertens, PhD

References

1. Schalla C, Trümper A: Entwicklung eines virtuellen klinischen Kernspintomographen. Diplomarbeit 1999. Interner Bericht der Universität Dortmund, Fachbereich Informatik.
   
   
2. Hackländer T, Schalla C, Trümper A, Mertens H, Hiltner J: Virtueller Kernspintomograph. 81. Deutscher Röntgenkongreß, Wiesbaden. RoFo Fortschr Geb Röntgenstr Neuen Bildgeb Verfahr 172 (2000) S135.
   
   
3. Hacklaender T, Schalla C, Truemper A, Mertens H, Hiltner J, Cramer BM: A Virtual MR Scanner for Education. RSNA 2002, 88th Scientific Assembly and Annual Meeting, Chicago, USA. Radiology 225 (P) (2002) 757.
   
   
4. Hackländer T, Mertens H, Cramer BM: Computersimulation eines klinischen Magnetresonanztomographen für Ausbildungszwecke. RoFo Fortschr Geb Röntgenstr Neuen Bildgeb Verfahr 176 (2004) 1151-1156
   
   
5. Hackländer T, Mertens H: Virtual MRI: A PC based simulation of a clinical MR scanner. Acad Radiol 12,1 (2005) 85-96