.. DO NOT EDIT. .. THIS FILE WAS AUTOMATICALLY GENERATED BY SPHINX-GALLERY. .. TO MAKE CHANGES, EDIT THE SOURCE PYTHON FILE: .. "generated/gallery/10-gradient-echo/gre_stack_of_spirals3D_sequence.py" .. LINE NUMBERS ARE GIVEN BELOW. .. only:: html .. note:: :class: sphx-glr-download-link-note :ref:`Go to the end ` to download the full example code. .. rst-class:: sphx-glr-example-title .. _sphx_glr_generated_gallery_10-gradient-echo_gre_stack_of_spirals3D_sequence.py: =================================== 3D stack-of-spirals gradient echo =================================== A slab-selective spoiled excitation is followed by one spiral interleaf with Cartesian partition encoding. Gradient and RF spoiling suppress residual transverse coherence between repetitions. TR, flip angle, and TE determine contrast. Stack-of-spirals SPGR supports rapid 3D structural and dynamic imaging. .. GENERATED FROM PYTHON SOURCE LINES 12-32 .. GENERATED FROM PYTHON SOURCE LINES 33-37 Sixteen interleaves ------------------- Sixteen interleaves at every partition. .. GENERATED FROM PYTHON SOURCE LINES 37-45 .. code-block:: Python import pypulseqpp as pp from pypulseqpp.sequences import gre_stack_of_spirals3D_sequence baseline = gre_stack_of_spirals3D_sequence(n=96, n_z=8, n_shots=16, tr=None, n_dummy=0) print(f"{baseline.num_blocks} blocks, {baseline.duration()[0]:.2f} s") .. rst-class:: sphx-glr-script-out .. code-block:: none 512 blocks, 0.91 s .. GENERATED FROM PYTHON SOURCE LINES 46-48 Sequence diagram ---------------- .. GENERATED FROM PYTHON SOURCE LINES 48-51 .. code-block:: Python baseline.paper_plot() .. image-sg:: /generated/gallery/10-gradient-echo/images/sphx_glr_gre_stack_of_spirals3D_sequence_001.png :alt: gre stack of spirals3D sequence :srcset: /generated/gallery/10-gradient-echo/images/sphx_glr_gre_stack_of_spirals3D_sequence_001.png :class: sphx-glr-single-img .. GENERATED FROM PYTHON SOURCE LINES 52-56 Sampling order -------------- The interleaves of every partition, over the three k-space axes. .. GENERATED FROM PYTHON SOURCE LINES 56-59 .. code-block:: Python pp.plot.plot_kspace(baseline, color_by="shot") .. image-sg:: /generated/gallery/10-gradient-echo/images/sphx_glr_gre_stack_of_spirals3D_sequence_002.png :alt: gre stack of spirals3D sequence :srcset: /generated/gallery/10-gradient-echo/images/sphx_glr_gre_stack_of_spirals3D_sequence_002.png :class: sphx-glr-single-img .. GENERATED FROM PYTHON SOURCE LINES 60-65 Fewer interleaves ----------------- Halving the interleaf count halves the number of repetitions and doubles the spiral pitch. The resulting peripheral sampling is below the Nyquist rate. .. GENERATED FROM PYTHON SOURCE LINES 65-79 .. code-block:: Python alternative = gre_stack_of_spirals3D_sequence( n=96, n_z=8, n_shots=8, tr=None, n_dummy=0 ) .. rst-class:: sphx-glr-script-out .. code-block:: none blocks duration (s) acquisitions 16 interleaves 512 0.91 128 8 interleaves 256 0.61 64 .. GENERATED FROM PYTHON SOURCE LINES 80-82 .. code-block:: Python pp.plot.plot_kspace(alternative, color_by="shot") .. image-sg:: /generated/gallery/10-gradient-echo/images/sphx_glr_gre_stack_of_spirals3D_sequence_003.png :alt: gre stack of spirals3D sequence :srcset: /generated/gallery/10-gradient-echo/images/sphx_glr_gre_stack_of_spirals3D_sequence_003.png :class: sphx-glr-single-img .. rst-class:: sphx-glr-timing **Total running time of the script:** (0 minutes 3.200 seconds) .. _sphx_glr_download_generated_gallery_10-gradient-echo_gre_stack_of_spirals3D_sequence.py: .. only:: html .. container:: sphx-glr-footer sphx-glr-footer-example .. container:: sphx-glr-download sphx-glr-download-jupyter :download:`Download Jupyter notebook: gre_stack_of_spirals3D_sequence.ipynb ` .. container:: sphx-glr-download sphx-glr-download-python :download:`Download Python source code: gre_stack_of_spirals3D_sequence.py ` .. container:: sphx-glr-download sphx-glr-download-zip :download:`Download zipped: gre_stack_of_spirals3D_sequence.zip ` .. only:: html .. rst-class:: sphx-glr-signature `Gallery generated by Sphinx-Gallery `_