TITLE:
Correcting the Variations of BOLD Signal Due to Susceptibility Gradients and Its Application
AUTHORS:
Lifang Zhao, Lianjun Zhang, Gang Liu
KEYWORDS:
BOLD Signal, Susceptibility Gradients, FMRI, Percentage Signal Change
JOURNAL NAME:
Journal of Computer and Communications,
Vol.7 No.11,
November
5,
2019
ABSTRACT: Blood oxygenation level dependence signal (BOLD) for functional magnetic resonance imaging (FMRI), is the use of blood magnetization depending on the oxygenation state of hemoglobin. Susceptibility gradient can shift and skew k-space trajectories and it leads to echo time shift and BOLD sensitivity change. FMRI can be used to detect the signal, the change of the susceptibility gradient of the signal and the distortion of k space trajectory, resulting in echo time shift and BOLD sensitivity change. Using the percentage signal change (PSC) and calibration function, it can be applied to many different fields, such as age-related research. In this paper, the performance of BOLD signal change correction based on sensitivity gradient was verified by real data group calculation, and methods of further improving the calculation speed were analyzed. This paper also analyzed the performance of correcting the variations of BOLD Signal due to susceptibility gradients with real data set, and identified the computational issues that need to be improved for further research.