| 摘要 |
A fast, efficient, qualitatively high-grade shim is enabled in a magnetic resonance apparatus and a method to set shim parameters of a magnetic resonance apparatus, to prepare the implementation of a magnetic resonance examination of a patient with an imaging medical magnetic resonance apparatus having a displaceable patient bed, wherein an examination region of the patient that is to be examined is larger than an imaging region of the magnetic resonance apparatus. Field inhomogeneities are measured while the examination region is moved through the imaging region by a continuous displacement of the patient bed with the patient positioned thereon. Information representing field inhomogeneities (B0 map) is acquired at multiple positions of the patient bed from respective magnetic resonance signals received at these positions. Information representing field inhomogeneities is acquired by excitation of multiple respective slices before the readout of the echo of the first of these slices, with one echo train composed of multiple echoes being generated per excitation signal. Shim parameters of the magnetic resonance apparatus are adjusted dependent on the measured information. A magnetic resonance examination of the examination region is implemented with the apparatus shimmed according to the shim parameters.
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