In-plane segmentation can be susceptible to shot-specific variations in B0. If this is not taken care of, it can cause image ghosting of the resulting functional time series. Here we tried to minimize the in-plane segmentation related ghosting with multiple parallel strategies: a.) A variable echo-time shift was included for each segment to match the signal and phase of segments in the presence of T2* decay and a spatially inhomogeneous phase (as implemented by Stirnberg et al., (2016)). b.) The IR-loop and the segmentation loop were harmonized to have the same signal across in-plane segments (Stirnberg et al. 2019). c) The phase navigators for phase correction across segments and across odd and even lines were excluded from the EPI module and acquired as a global adjustment at the beginning of the time series (Stirnberg et al. 2017). d.) We used the advanced algorithms of the vendor to implement phase offset correction (OnlinePCCross-CorrAcrossSegmentsEPI) as described by Heid et al. (2000).
