Measuring transverse relaxation rates of the major brain metabolites from single‐voxel PRESS acquisitions at a single TE. Issue 6 (6th January 2021)

• Record Type: Journal Article
• Authors: Nosrati, Reyhaneh; Balasubramanian, Mukund; Mulkern, Robert
• Is Part Of: Magnetic resonance in medicine. Volume 85:Issue 6(2021)
• Page Start: 2965
• Page End: 2977
• Publication Date: 2021-01-06
• Subjects: choline -- creatine -- N‐acetylaspartate -- PRESS -- transverse relaxation; Nuclear magnetic resonance -- Periodicals; Electron paramagnetic resonance -- Periodicals; 616.07548
• DOI: 10.1002/mrm.28644
• Languages: English
• ISSNs: 0740-3194

Abstract

Abstract : Purpose: To compare transverse relaxation rates of brain metabolites estimated from single‐TE PRESS acquisitions with more conventionally derived rates estimated from multiple‐TE PRESS acquisitions. Methods: Single‐voxel (8 mL) PRESS data within white matter from 6 subjects were acquired at five different TEs. Transverse relaxation rates R2 of N‐acetylaspartate, creatine, and choline were estimated from a single TE using full versus right‐side‐only sampling of the echo. These R2 values were compared with R2Hahn values obtained from the multiple‐TE PRESS acquisitions. Results: Following baseline subtraction and RMS weighting, interindividual mean R2 values from TE = 288 ms magnitude spectra for choline, creatine, and N‐acetylaspartate were highly correlated with respective R2Hahn values (r 2 = 0.99). Paired individual measurements at this TE showed less correlation (r 2 = 0.48), primarily due to the N‐acetylaspartate resonance. Using TE = 360 ms data for N‐acetylaspartate and 288 ms for choline and creatine resulted in an improved correlation coefficient (r 2 = 0.80). The average absolute intra‐individual differences in the estimated R2 s between single‐TE and Hahn method was 9.6 ± 7.7%. Conclusion: For the major brain metabolite singlets, R2Hahn values showed correlations with more fragile measurements of R2 from a single TE that are worthy of interest. Because the left side of long‐TE spin echoes is available "for free" from an acquisition perspective, and although the single‐TE method for estimating R2 values is associated with lower precision, the reduction in scan time may be clinically helpful.