Abstract:
:Proton MR spectroscopy ((1)H-MRS) has been used for in vivo quantification of intracellular triglycerides within the sarcolemma. The purpose of this study was to assess whether breath-hold dual-echo in- and out-of-phase MRI at 3.0 T can quantify the fat content of the myocardium. Biases, including T(1), T*(2), and noise, that confound the calculation of the fat fraction were carefully corrected. Thirty-four of 46 participants had both MRI and MRS data. The fat fractions from MRI showed a strong correlation with fat fractions from MRS (r = 0.78; P < 0.05). The mean myocardial fat fraction for all 34 subjects was 0.7 +/- 0.5% (range: 0.11-3%) assessed with MRS and 1.04 +/- 0.4% (range: 0.32-2.44%) assessed with in- and out-of-phase MRI (P < 0.05). Scanning times were less than 15 sec for Dixon imaging, plus an additional minute for the acquisition used for T*(2) calculation, and 15-20 min for MRS. The average postprocessing time for MRS was 3 min and 5 min for MRI including T*(2) measurement. We conclude that the dual echo method provides a rapid means to detect and quantifying myocardial fat content in vivo. Correction/adjustment for field inhomogeneity using three or more echoes seems crucial for the dual echo approach.
journal_name
Magn Reson Medjournal_title
Magnetic resonance in medicineauthors
Liu CY,Redheuil A,Ouwerkerk R,Lima JA,Bluemke DAdoi
10.1002/mrm.22289subject
Has Abstractpub_date
2010-04-01 00:00:00pages
892-901issue
4eissn
0740-3194issn
1522-2594journal_volume
63pub_type
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