Speaker
Description
Up today, hybrid nuclear medicine image systems basically integrate two techniques: X-ray based or MRI for anatomic images and PET for the functional ones [1]. These systems need instrumentation susceptible to interfere with the MRI signal during the photon-charges conversion process in the photomultiplier or other similar detector techniques.
We propose a hybrid system whose main characteristic is that the gamma image is obtained directly by MRI [2,3] (patent pending).
The detector is based on a radiosensitive gel whose absorbed radiation produces polymerization changes. These changes are linearly dependent on T2 relaxation time [4] among other MRI parameters.
In this work, the features of the gamma detector gel are explored as hybrid image technique by GEANT4 Monte Carlo simulations, as well as the radiation process and statistical noise on radiation MRI images.
It is presented the preliminary designs using two different collimators, comparing the limits and optimal conditions of sensibility as a function of the absorbed dose and SNR in the MRI.
Finally, an experimental prototype for one-dimensional images is tested proving the viability of the previous simulations.
[1] Andrew B. Rosenkrantz, Kent Friedman, Hersh Chandarana, et al. Current Status of Hybrid PET/MRI in Oncologic
Imaging American Journal of Roentgenology. 2016;206: pp 162-172.
[2] L. Agulles-Pedrós and A. Abril One dimensional spatial resolution optimization on a hybrid low field MRI-gamma
detector AIP Conference Proceedings (2016) 1753, 080020;
[3] A. Abril and L. Agulles-Pedrós 2D dose distribution images of a hybrid low field MRI-γ detector AIP Conference
Proceedings (2016) 1753, 080012;
[4] C Baldock. Topical review: Polymer gel dosimetry, The Journal of Physics Medical Biology, 2010 Feb 11th; 55(5):
R1–R63.
