Patent ID: 11874355
Assignee: SIEMENS HEALTHCARE LIMITED
Field: Measurement (Instruments)
Classification: CPC G | IPC G

Claim 0:
1. A method for determining parameter values in image points of an examination object in a magnetic resonance (MR) system by a magnetic resonance fingerprinting (MRF) technique, the method comprising:
loading a number of comparison signal waveforms, which are each assigned to predetermined values of the parameters to be determined, wherein the comparison signal waveforms are established using predetermined recording parameters, and the predetermined recording parameters comprise:
a number of signal measurements,
recording parameters that characterize a radio frequency (RF) pulse to be applied for a respective signal measurement, and
repetition times that specify a respective time interval between excitations of consecutive signal measurements;

acquiring at least one image point time series of the examination object with the aid of an MRF recording method in such a manner that the acquired image point time series are comparable with the loaded comparison signal waveforms;
carrying out a signal comparison of at least one section of the respective signal waveform of the acquired one image point time series with a corresponding section of loaded comparison signal waveforms to establish similarity values between the acquired image point time series and the respective comparison signal waveforms;
determining the values of the parameters to be determined on the basis of the n most similar comparison signal waveforms determined, wherein n is a predetermined natural number; and
storing and/or outputting the values of the parameters to be determined for the respective image point,
wherein, during reading out of signals for creation of the image point time series, readout gradients, which are used for spatial encoding of the signals read out, are switched in at least one readout gradient direction, and
wherein after an ending of the reading out of the signals, compensation gradients, which lead the zero moment of the readout gradient to the value zero, are switched in the at least one readout gradient direction.