System And Method For Thin Slice Acquisition Using Saturation Spin Labeling (TASSL) MR Angiography

摘要

A system and method is provided for magnetic resonance angiography (MRA) that includes performing a labeling pulse to a labeling region having a first portion of a vascular system of a subject. The labeling pulse includes at least one excitation pulse and a slab-selective magnetic field gradient to saturate spins flowing from the labeling region and into an imaging region. The process also includes observing a delay period and performing an imaging pulse sequence to collect a label imaging data set from one or more views through the imaging region using an excitation pulse. The preceding is repeated with a TR selected to ensure that the spins flowing within the imaging region are kept substantially saturated during a majority of repetitions. The process also includes acquiring a non-labeling imaging data set without saturating spins and reconstructing an image using the labeling imaging data set and the non-labeling imaging data.

主权项

1. A method for acquiring a magnetic resonance angiography (MRA) image of a portion of a vascular system of a subject using a magnetic resonance imaging system, the method including steps comprising:
i) performing a labeling pulse to a labeling region having a first portion of a vascular system of a subject extending through the labeling region to label spins moving within the first labeling region, wherein the labeling pulse includes at least one excitation pulse in combination with a slab-selective magnetic field gradient to saturate spins flowing from the labeling region and into an imaging region extending less than 32 mm along a direction of flow of the spins flowing from the labeling region into the imaging region; ii) observing a delay period that is less than a T1 relaxation time of the spins flowing from the labeling region into the imaging region; iii) performing an imaging pulse sequence to collecting a label imaging data set from one or more views through the imaging region using an excitation pulse with a value of a flip angle that is less than twice a value of a repetition time (TR) of the imaging pulse sequence; and iv) repeating at least steps i) through iii) with a TR selected to ensure that the spins flowing within the imaging region are kept substantially saturated during a majority of repetitions of step iii); v) acquiring a non-labeling imaging data set from the imaging region without saturating spins flowing from the labeling region and into the imaging region; vi) reconstructing an image using the labeling imaging data set and the non-labeling imaging data set to create a magnetic resonance angiography image.