Magnetic resonance imaging based on altering the shape of the inversion region in pulsed arterial spin labeling

A non-transitory computer-readable storage medium embodying instructions to cause a magnetic resonance imaging system to perform operations comprising:

• generating an inversion slab;
• modifying a shape of the inversion slab by modulating a plurality of in-plane gradients on a thickness of the inversion slab, wherein the modifying the shape of the slab comprises applying a hyperbolic secant inversion pulse with sech/tanh modulation in amplitude and frequency and a Z gradient;
• measuring one or more of velocities and lengths of at least some of a plurality of feeding arteries in the inversion slab;
• and
• assigning an inversion thickness of the inversion slab to at least some of the plurality of feeding arteries by matching a temporal bolus width with an inter-pulse spacing of the at least some of the plurality of feeding arteries.

A magnetic resonance imaging (MRI) system, comprising:

• a scanner comprising a magnet, gradient coils and a radio frequency (RF) system to perform operations comprising:
• applying a gradient field and generating RF pulses to a tissue of interest to create a slab within the tissue of interest in which magnetic inversion is generated,
• modifying a shape of the slab having the magnetic inversion by modulating a plurality of in-plane gradients on a thickness of the slab, and acquiring magnetic resonance signals based on the applied RF pulses, wherein modifying the shape of the inversion slab comprises applying a hyperbolic secant inversion pulse with sech/tanh modulation in amplitude and frequency and a Z gradient;
• and
• a data processing system in communication with the scanner to receive the acquired magnetic resonance signals and process the received magnetic resonance signal to generate MRI images of the tissue of interest to improve the temporal signal-to-noise ratio (tSNR), the data processing system configured to:
• measure one or more of velocities and lengths of at least some of a plurality of feeding arteries in the inversion slab;
• and
• assign an inversion thickness of the inversion slab to at least some of the plurality of feeding arteries by matching a temporal bolus width with an inter-pulse spacing of the at least some of the plurality of feeding arteries.