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Perhaps some more info might be helpful...

These images were acquired with a gradient echo sequence, FOV 19.2 cm, 64 x 64 matrix with 3 mm slices (no gap), to match my echo planar images (EPI). The TR = 775 ms, TE = 10 ms. I've turned off gradwarp and fermi filtering (i.e., nograd = 1, nofermi =1), and set the image reconstruction to match the acquisition resolution (i.e., rhrcxres = 64, rhrcyres = 64). 

Importantly (or so I'm lead to believe), while these images were acquired on an 8 channel headcoil, they represent the data from only a single coil (i.e., saveinter = 1). But it doesn't make a difference, the image reconstructed from the eight coils also has the black horizontal stripes. In fact, nothing I've tried makes any difference to these stripes; leave gradwarp on, fermi filtering on, change the matrix size to 128 x 128, field of view to 24 cm ...

Which makes me think they are either a product of the gradient echo sequence our radiographer has used, in which case I need a new sequence (any helpers?). Or, they are due to some unforeseen variable such as "silent" partial Fourier or dropping k-space?

Any hints greatly appreciated,

Rich