Using PINS pulses to saturate inflow effects from slice gaps in functional MRI

In this work, we demonstrate the use of PINS pulses to mitigate unwanted inflow effects in 2D multi-slice sequences. A PINS pulse was played prior to slice-selective excitation to saturate the magnetization within all slice gaps. Bloch simulation and flow-phantom experiments show inflow effects can be removed completely. Functional scans using twice-refocused spin echo suggest that inflow effects may have noticeable contributions to SE-BOLD fMRI response. This PINS implementation allows us to further understand fMRI signal dynamics by modulating the inflow effect.