Off-Resonance Correction for Vessel-Selective Pseudo-Continuous Arterial Spin Labeling Imaging

A magnetic resonance imaging (MRI) method for effecting MR imaging based upon arterial spin labeling (ASL), said MRI method comprising:

• placing an object into an MRI gantry including a static magnetic field coil, gradient magnetic field coils, at least one radio frequency (RF) coil configured to couple with an object located in an imaging volume;
• performing an RF and gradient magnetic field pulse sequence comprising (1) applying a tagging pulse train to a tagging area located upstream from an imaging area, followed by applying a first imaging pulse train to the imaging area, and (2) applying a control pulse train to a control area followed by applying a second imaging pulse train to the imaging area;
• receiving a plurality of first digital data and a plurality of second digital data corresponding respectively to nuclear magnetic resonance (NMR) signals responsive to the first imaging pulse train and to NMR signals responsive to the second imaging pulse train;
• forming, from each of the plurality of first digital data, a respective tag image and, from each of the plurality of second digital data, a respective control image;
• forming a plurality of perfusion images of the object, each of the perfusion images formed by one of the tag images and a corresponding one of the control images, each perfusion image corresponding to a respective phase offset;
• generating a corrected perfusion image by, for respective points of the corrected perfusion image, fitting corresponding points from each of the plurality of perfusion images to a polynomial function;
• and
• outputting the corrected perfusion image to a display, or data storage in a non-transient digital data storage medium, or an outbound data transmission port.

A non-transitory computer readable storage medium, having executable computer program instructions recorded thereon, which when executed by at least one processor of a magnetic resonance imaging (MRI) system having an MRI gantry including a static magnetic field coil, gradient magnetic field coils, at least one radio frequency (RF) coil configured to couple with an object located in an imaging volume, causes the at least one processor to generate a final MRI image, by performing operations comprising:

• configuring a sequence controller to perform an RF and gradient magnetic field pulse sequence comprising (1) applying a tagging pulse train to a tagging area located upstream from an imaging area, followed by applying a first imaging pulse train to the imaging area, and (2) applying a control pulse train to a control area followed by applying a second imaging pulse train to the imaging area;
• receiving a plurality of first digital data and a plurality of second digital data corresponding respectively to nuclear magnetic resonance (NMR) signals responsive to the first imaging pulse train and to NMR signals responsive to the second imaging pulse train;
• forming, from each of the plurality of first digital data, a respective tag image and, from each of the plurality of second digital data, a respective control image;
• forming a plurality of perfusion images of the object, each of the perfusion images formed by one of the tag images and a corresponding one of the control images, each perfusion image corresponding to a respective phase offset;
• generating a corrected perfusion image by, for respective points of the corrected perfusion image, fitting corresponding points from each of the plurality of perfusion images to a polynomial function;
• and
• outputting the corrected perfusion image to a display, or data storage in a non-transient digital data storage medium, or an outbound data transmission port.