Noninvasive temperature mapping with MRI using chemical shift water-fat separation.
Published
Journal Article
Tissues containing both water and lipids, e.g., breast, confound standard MR proton reference frequency-shift methods for mapping temperatures due to the lack of temperature-induced frequency shift in lipid protons. Generalized Dixon chemical shift-based water-fat separation methods, such as GE's iterative decomposition of water and fat with echo asymmetry and least-squares estimation method, can result in complex water and fat images. Once separated, the phase change over time of the water signal can be used to map temperature. Phase change of the lipid signal can be used to correct for non-temperature-dependent phase changes, such as amplitude of static field drift. In this work, an image acquisition and postprocessing method, called water and fat thermal MRI, is demonstrated in phantoms containing 30:70, 50:50, and 70:30 water-to-fat by volume. Noninvasive heating was applied in an Off1-On-Off2 pattern over 50 min, using a miniannular phased radiofrequency array. Temperature changes were referenced to the first image acquisition. Four fiber optic temperature probes were placed inside the phantoms for temperature comparison. Region of interest (ROI) temperature values colocated with the probes showed excellent agreement (global mean +/- standard deviation: -0.09 +/- 0.34 degrees C) despite significant amplitude of static field drift during the experiments.
Full Text
Duke Authors
Cited Authors
- Soher, BJ; Wyatt, C; Reeder, SB; MacFall, JR
Published Date
- May 2010
Published In
Volume / Issue
- 63 / 5
Start / End Page
- 1238 - 1246
PubMed ID
- 20432295
Pubmed Central ID
- 20432295
Electronic International Standard Serial Number (EISSN)
- 1522-2594
Digital Object Identifier (DOI)
- 10.1002/mrm.22310
Language
- eng
Conference Location
- United States