Fielden SW, Zhao L, Miller GW, Feng X, Geeslin M, Dallapiaza RF, Elias WJ, Wintermark M, Pauly KB, Meyer CH. A spiral-based volumetric acquisition for MR temperature imaging.
Magn Reson Med 2018;
79:3122-3127. [PMID:
29115692 PMCID:
PMC6377207 DOI:
10.1002/mrm.26981]
[Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2017] [Revised: 09/28/2017] [Accepted: 09/29/2017] [Indexed: 11/09/2022]
Abstract
PURPOSE
To develop a rapid pulse sequence for volumetric MR thermometry.
METHODS
Simulations were carried out to assess temperature deviation, focal spot distortion/blurring, and focal spot shift across a range of readout durations and maximum temperatures for Cartesian, spiral-out, and retraced spiral-in/out (RIO) trajectories. The RIO trajectory was applied for stack-of-spirals 3D imaging on a real-time imaging platform and preliminary evaluation was carried out compared to a standard 2D sequence in vivo using a swine brain model, comparing maximum and mean temperatures measured between the two methods, as well as the temporal standard deviation measured by the two methods.
RESULTS
In simulations, low-bandwidth Cartesian trajectories showed substantial shift of the focal spot, whereas both spiral trajectories showed no shift while maintaining focal spot geometry. In vivo, the 3D sequence achieved real-time 4D monitoring of thermometry, with an update time of 2.9-3.3 s.
CONCLUSION
Spiral imaging, and RIO imaging in particular, is an effective way to speed up volumetric MR thermometry. Magn Reson Med 79:3122-3127, 2018. © 2017 International Society for Magnetic Resonance in Medicine.
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