Christoph Zöllner^{1}, Sophia Kronthaler^{1}, Stefan Ruschke^{1}, Jürgen Rahmer^{2}, Johannes M. Peeters^{3}, Holger Eggers^{2}, Peter Börnert^{2}, Rickmer F. Braren^{1}, and Dimitrios C. Karampinos^{1}

^{1}Department of Diagnostic and Interventional Radiology, Technical University of Munich, München, Germany, ^{2}Philips Research Laboratory, Hamburg, Germany, ^{3}Philips Healthcare, Best, Netherlands

Stack-of-stars-type radial k-space trajectories employing golden-angle ordering have been becoming popular for either free breathing or navigator-gated volumetric T1-weighted imaging of the abdomen and heart. Most methods for compensating radial k-space trajectory errors induced by eddy currents and system delays are based either on the acquisition of calibration lines with opposite polarity or on the processing of approximately anti‐parallel spokes from the actual radial acquisition. This work shows that a trajectory correction based on a gradient system impulse response function improves image quality in high-resolution gated golden-angle radial Dixon imaging.

$$$k_0=\underset{k_0^*}{arg\,min}\left\Vert\frac{\partial\left|\mathfrak{F}\left(p^+e^{-i{\pi}{k_0^*m}}\right)\right|}{\partial{k}}-\frac{\partial\left|\mathfrak{F}\left(p^-e^{+i\pi{k_0^*m}}\right)\right|}{\partial{k}}\right\Vert_2$$$

where p± denote the complex 1D image space profiles measured with opposite readout gradient polarity and $$$\mathfrak{F}$$$ is the discrete Fourier transform function

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