B0 eddy currents are a subtle but important source of artifact in spiral MRI. As the gradient amplitude changes, B0 eddy currents produce time dependent B0 field shifts on the order of hundreds of hertz (see figure 1) and, consequently, time dependent phase shifts in the measured data. Previously, it has been shown that B0 eddy currents cause artifacts in 3D projection reconstruction sequences¹ and blurriness in combined spiral-in/out images². This work demonstrates the importance of accounting for B0 eddy currents in all spiral sequences.Sagittal spiral-out MPRAGE data and axial spiral-in/out TSE data were acquired in a healthy volunteer. The method of Brodsky et al.¹ was used to measure the phase produced by B0 eddy currents during the spiral acquisitions. Data were corrected by applying the conjugate of the measured B0 eddy current induced phase to the spiral imaging data. All data were processed and reconstructed in GPI³ using standard gridding reconstruction. The measured B0 eddy current induced phase was gridded to yield maps of the B0 phase distribution over k-space. The instantaneous slew rate and resultant measured f0 shift due to B0 eddy currents are shown in figure 1 for a single spiral interleave. As expected, the B0 eddy currents depend upon the rate at which the gradient amplitude is changing. Figure 2 shows gridded B0 eddy current phase maps. The B0 eddy currents produce a roughly linear phase across k-space in the axial case, and a non-linear distribution of B0 eddy current phase in the sagittal case. The resultant image artifacts from the B0 eddy currents are highlighted in figure 3. The linear B0 eddy current phase across k-space, in the axial case, causes opposite shifts in image space for the spiral-in and spiral-out portions of the acquisition and, consequently, blurriness in the combined spiral-in/out TSE image. The non-linear distribution of B0 eddy current phase in the sagittal case instead produces signal pileups and voids somewhat reminiscent of chemical shift artifacts. The artifacts are favorably improved in both cases by correcting for the B0 eddy current phase.This work has demonstrated that B0 eddy currents can produce substantial artifacts in any spiral acquisition. These artifacts can be subtle in nature and difficult to distinguish from blurring, k-space trajectory errors, and chemical shift. It should be noted that the results shown here are for a single scanner. The size and distribution of B0 eddy currents are expected to vary from scanner to scanner. Nevertheless, these effects should be taken into consideration for any high resolution spiral imaging.