Christina Triantafyllou1,2, Jonathan R. Polimeni2, Mattijs Elschot2,3, Lawrence L. Wald2,4
1A.A. Martinos Imaging Center, McGovern Institute for Brain Research, MIT, Cambridge, MA, USA; 2A.A. Martinos Center for Biomedical Imaging, Department of Radiology, MGH, Charlestown, MA, USA; 3Department of Biomedical Engineering, Eindhoven University of Technology, Eindhoven, Netherlands; 4Harvard-MIT Division of Health Sciences and Technology, MIT, Cambridge, MA, USA
The physiological noise in both spin echo and gradient echo EPI sequences as a function of (thermal) image SNR (SNR0) is investigated by modulating the spatial resolution, receive coil, and field strength. Our findings demonstrate that physiological noise in both sequences exhibit similar properties and the relationship between time-course SNR (tSNR) and SNR0 is well described by the same model. The largest gains in tSNR as a function of voxel size occurred at the highest spatial resolution. At coarser spatial resolutions, both field strengths and sequences showed asymptotic behavior, with higher field strengths nearing the asymptote at smaller voxel volumes.