load_ismrmrd_raw#

deepinv.utils.load_ismrmrd_raw(filename, ifft_slice_dim=False)[source]#

Load ISMRMRD hdf5 raw Cartesian multi-coil MRI data.

Saves the acquired lines of an ISMRMRD .h5 dataset onto a Cartesian k-space grid of zeros as (1, 2, N, D, H, W) where N = num coils, D = slice/depth and (H, W) = 2D plane.

The D dim is detected automatically for 2D vs 3D:

  • 3D acquisition: loads the entire 3D k-space, with D = readout and (H, W) = (partition, phase-encode).

  • 2D slice-based acquisition: loads the first slice only, with D = 1 (singleton) and (H, W) = (phase-encode, readout).

Code derived from ISMRMRD and examples.

The dataset requirers ismrmrd: pip install ismrmrd

Only the first average, contrast, phase, repetition and set is kept. Noise scans are dropped.

Note

Readout oversampling is removed by default, since scanners oversample the (fully-sampled) readout (typically 2x) to avoid frequency-encode aliasing, which doubles the readout FOV and is redundant for reconstruction.

Parameters:

  • filename (str) – path to the ISMRMRD .h5 file.

  • ifft_slice_dim (bool) – if True, inverse FFT the slice/depth axis D so it is returned in image space, ready to index slices. Note for 2D it is ignored.

Returns:

real tensor of shape (1, 2, N, D, H, W), where N = num coils.

Return type:

Tensor