Simple approach to improve time series fMRI stability: STAbility-weighted Rf-coil Combination (STARC)

Advanced EPI -especially at high resolutions- is often limited with signal instabilities arising from a variety of unwanted artifacts. These include: GRAPPA ghosts interference, Nyquist ghosts, phase offset interference patterns, and fat rings. The sources of these artifacts are all somewhat locally confined and are differently pronounced in different elements of multi coil arrays. Here we propose a simple approach of stability-weighted RF-coil combination (STARC) that reduces the likelihood of those artifacts. It increases tSNR and fMRI sensitivity up to 50% without a loss in quantifiability.