Fast Calculation of T-2 Relaxation Time in Magnetic Resonance Imaging

0507187 - ÚPT 2020 RIV GB eng C - Conference Paper (international conference)
Mikulka, J. - Dvořák, Pavel
Fast Calculation of T-2 Relaxation Time in Magnetic Resonance Imaging.
PIERS 2014 Guangzhou Proceedings. Cambridge: The Electromagnetics Academy, 2014, s. 2331-2335. ISBN 978-1-934142-28-8.
[Progress in Electromagnetics Research Symposium (PIERS). Guangzhou (CN), 25.08.2014-28.08.2014]
R&D Projects: GA ČR GAP102/12/1104
Institutional support: RVO:68081731
Keywords : magnetic resonance imaging * T-2 relaxation
OECD category: Electrical and electronic engineering

The main parameters displayed by means of magnetic resonance include, for example, relaxation times T-1 and T-2 or diffusion parameters. This paper presents the computation of relaxation time T-2 measured indirectly with the Spin Echo method. The sensing coil of the tomograph provides a signal in which the important factor is the location of the peaks from individual measurements. These points must be interleaved with an exponential function. The relaxation time T-2 can be directly determined from the exponential shape. The described process has to be repeated for each pixel of the sensed tissue, and this requirement makes the processing of larger images very demanding in terms of both the actual computation and the time needed for the entire operation. More concretely, if we assume the common resolution of 256x256, 20 slices, and five measurements with different times TE, it is necessary to reconstruct 1.3.106 exponential functions in total, which requires the processing of more than 6MB of data. At present, such computation lasts approximately 3 minutes if performed by means of a regular PC. The author discusses various approaches to the parallelization of the given problem. In the described context, the time required for the processing of the applied three-dimensional image was shortened to 300 ms thanks to simple interpolation approach. The final section of the paper comprises a detailed comparison of the computation times characterizing both the sequential and the parallel solutions.
Permanent Link: http://hdl.handle.net/11104/0298387