Rapid inner‐volume imaging in the steady‐state with 3D selective excitation and small‐tip fast recovery imaging
Year: 2015
Type: article
Abstract: PURPOSE: Develop a method for rapid three-dimensional inner-volume (IV), or reduced field-of-view, steady-state imaging. METHODS: Tailored radiofrequency pulses for exciting a three-dimensional IV were designed using a recently proposed algorithm and used in three different sequences: spoiled gradient echo, balanced steady-state free precession, and "small-tip fast recovery" (STFR) which uses a "tip-up" RF pulse after the readout to fast recover spins to the longitudinal axis. The inner- and outer-volume (OV) steady-state signals were analyzed. To demonstrate the potential utility of the proposed method, segmented stack-of-spirals reduced field-of-view images in a volunteer were acquired. RESULTS: For a given three-dimensional IV excitation pulse, STFR can achieve higher IV/OV signal ratio compared with spoiled gradient echo and balanced steady-state free precession. For spoiled gradient echo and balanced steady-state free precession, this ratio is significantly lower than that produced by a single IV excitation. For STFR, this ratio exceeds that produced by a single IV excitation, due to partial OV saturation produced by the nonspatially selective tip-up pulse. Reduced FOV STFR stack-of-spirals imaging with 2-fold under-sampling in both x-y and z is demonstrated. CONCLUSION: STFR provides an effective mechanism for OV suppression in steady-state IV imaging. The recently proposed joint pulse design method can be used in the STFR sequence to achieve fast reduced field-of-view imaging. Magn Reson Med 76:1217-1223, 2016. © 2015 Wiley Periodicals, Inc.
Source: Magnetic Resonance in Medicine
DOI: 10.1002/mrm.26026
Institution: University of Michigan
Language: English
Subfield: Radiology, Nuclear Medicine and Imaging
Field: Medicine
Domain: Health Sciences
Open Access status: green
OpenAlex ID: W1865855185