VARIABLE TR (vTR) FUNCTION IN FRESH BLOOD IMAGING (FBI)

摘要

A magnetic resonance imaging (MRI) system, method and/or computer readable medium is configured to obtain bright signal while having acceptable specific absorption rate (SAR) and acceptable scan time in Fast Advanced Spin Echo (FASE) or Single-shot Fast Spin Echo (SS-FSE) imaging used, for example, in non-contrast magnetic resonance angiography (NC-MRA) techniques like fresh blood imaging (FBI). Within RF pulse sequences used to acquire echo data, the TR intervals are varied in the slice encode direction. In some instances, the refocusing pulse flip angles too may be varied for RF pulse sequences such that central k-space have larger refocusing pulse flip angles than slices further towards the ends.

主权项

1. A magnetic resonance imaging (MRI) system comprising:
an MRI gantry having components including a static magnetic field generator, gradient magnetic field coils, at least one radio frequency (RF) coil configured to couple with an object located in an imaging volume, at least one RF transmitter and at least one RF receiver; an MRI sequence controller configured to control said gantry components so as to effect fresh blood imaging (FBI) of a three dimensional (3D) volume by:
eliciting systolic and diastolic sequences of nuclear magnetic resonance (NMR) echoes, from the object, which map to a 3D k-space having phase-encoded (PE) and slice-encoded (SE) dimensions;said sequences of NMR echoes being elicited by respectively corresponding single-shot RF pulse sequences that each have an excitation RF pulse followed by plural refocusing RF pulses; andsaid single-shot RF pulse sequences have variable repetition time (TR) intervals in the SE dimension, and at least one digital data processor configured to reconstruct a 3D diagnostic FBI image from said elicited systolic and diastolic sequences of NMR echoes.