Accuracy of equilibrium magnetization mapping in sliced two‐dimensional spoiled gradient‐recalled echo pulse sequence with variable flip angle. Issue 5 (6th February 2013)

• Record Type: Journal Article
• Authors: Kuribayashi, Hideto; Sekino, Masaki; Minowa, Takuya; Maitani, Yoshie; Ohsaki, Hiroyuki; Tsushima, Shohji; Hirai, Shuichiro; Ueda, Masayuki; Katayama, Yasuo
• Is Part Of: Journal of magnetic resonance imaging. Volume 38:Issue 5(2013)
• Page Start: 1245
• Page End: 1250
• Publication Date: 2013-02-06
• Subjects: Magnetic resonance imaging -- Periodicals; 616
• DOI: 10.1002/jmri.24023
• Languages: English
• ISSNs: 1053-1807

Abstract

<abstract abstract-type="main"> <title> <x xml:space="preserve">Abstract</x> </title> <sec id="jmri24023-sec-0001" sec-type="section"> <title>Purpose</title> <p>To evaluate the accuracy of an equilibrium magnetization (M<sub>0</sub>) map obtained using a two‐dimensional (2D) spoiled gradient‐recalled echo (SPGR) pulse sequence with variable flip angle (VFA).</p> </sec> <sec id="jmri24023-sec-0002" sec-type="section"> <title>Materials and Methods</title> <p>Single‐slice 2D SPGR images of 4% agar gel phantoms with different gadolinium‐diethylene triamine pentaacetic acid (Gd‐DTPA) concentrations (0–1 mM) were obtained with a VFA (2–30°). The 2D SPGR‐VFA data were acquired with different repetition times (TRs; 7.8–117.2 ms), Gaussian and sinc RF pulses, and different field strengths (4.7, 7, and 9.4 Tesla). M<sub>0</sub> and T<sub>1</sub> maps were calculated from the 2D SPGR‐VFA data. M<sub>0</sub> and T<sub>1</sub> values were compared with those calculated from free‐relaxed 2D gradient‐recalled echo (GRE) images and inversion recovery‐prepared 2D SPGR images. The M<sub>0</sub> and T<sub>1</sub> slice profiles were also investigated.</p> </sec> <sec id="jmri24023-sec-0003" sec-type="section"> <title>Results</title> <p>Consistent M<sub>0</sub> values were obtained, regardless of the different Gd concentrations, TRs, and pulse sequences. The M<sub>0</sub> slice profiles calculated from the sliced SPGR‐VFA data quantitatively reproduced those calculated from the free‐relaxed sliced GRE. In contrast, the T<sub>1</sub> values calculated from the 2D SPGR‐VFA data were underestimated at a high Gd concentration, short TR, and Gaussian RF pulse.</p> </sec> <sec id="jmri24023-sec-0004" sec-type="section"> <title>Conclusion</title> <p>M<sub>0</sub> values calculated from 2D SPGR‐VFA images are highly quantitative. J. Magn. Reson. Imaging 2013;38:1245–1250. © 2013 Wiley Periodicals, Inc.</p> </sec> </abstract>