Dynamic MR imaging of the temporomandibular joint using a balanced steady-state free precession sequence at 3T.
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ABSTRACT:
SUBMITTER: Yen P
PROVIDER: S-EPMC7964901 | biostudies-literature | 2013 Mar
REPOSITORIES: biostudies-literature
Publications
Dynamic MR imaging of the temporomandibular joint using a balanced steady-state free precession sequence at 3T.
Yen P P Katzberg R W RW Buonocore M H MH Sonico J J
AJNR. American journal of neuroradiology 20111027 3
The aim of our project was to develop an MR imaging protocol for dynamic imaging of the TMJ. We imaged a total of 24 joints in 12 subjects. We developed an imaging protocol on a 3T system using the true FISP sequence that yielded an acceptable spatial and temporal resolution for dynamic MR imaging. ...[more]
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Project description:PurposeBalanced steady-state free precession (bSSFP) sequences can provide superior signal-to-noise ratio efficiency for hyperpolarized (HP) carbon-13 (13 C) magnetic resonance imaging by efficiently utilizing the nonrecoverable magnetization, but managing their spectral response is challenging in the context of metabolic imaging. A new spectrally selective bSSFP sequence was developed for fast imaging of multiple HP 13 C metabolites with high spatiotemporal resolution.Theory and methodsThis novel approach for bSSFP spectral selectivity incorporates optimized short-duration spectrally selective radiofrequency pulses within a bSSFP pulse train and a carefully chosen repetition time to avoid banding artifacts.ResultsThe sequence enabled subsecond 3D dynamic spectrally selective imaging of 13 C metabolites of copolarized [1-13 C]pyruvate and [13 C]urea at 2-mm isotropic resolution, with excellent spectral selectivity (∼100:1). The sequence was successfully tested in phantom studies and in vivo studies with normal mice.ConclusionThis sequence is expected to benefit applications requiring dynamic volumetric imaging of metabolically active 13 C compounds at high spatiotemporal resolution, including preclinical studies at high field and, potentially, clinical studies. Magn Reson Med 78:963-975, 2017. © 2016 International Society for Magnetic Resonance in Medicine.
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