TY - JOUR
T1 - Chemical Exchange Saturation Transfer (CEST) MR Technique for Liver Imaging at 3.0 Tesla
T2 - an Evaluation of Different Offset Number and an After-Meal and Over-Night-Fast Comparison
AU - Deng, Min
AU - Chen, Shu Zhong
AU - Yuan, Jing
AU - Chan, Queenie
AU - Zhou, Jinyuan
AU - Wáng, Yì Xiáng J.
N1 - Funding Information:
This study was partially by grants from the Research Grants Council of the Hong Kong SAR (Project No. 476313 and Project No. SEG_CUHK02) and the National Institutes of Health (R01EB009731, R01CA166171).
Publisher Copyright:
© 2015, World Molecular Imaging Society.
PY - 2016/4/1
Y1 - 2016/4/1
N2 - Purpose: This study seeks to explore whether chemical exchange saturation transfer (CEST) magnetic resonance imaging (MRI) can detect liver composition changes between after-meal and over-night-fast statuses. Procedures: Fifteen healthy volunteers were scanned on a 3.0-T human MRI scanner in the evening 1.5–2 h after dinner and in the morning after over-night (12-h) fasting. Among them, seven volunteers were scanned twice to assess the scan–rescan reproducibility. Images were acquired at offsets (n = 41, increment = 0.25 ppm) from −5 to 5 ppm using a turbo spin echo (TSE) sequence with a continuous rectangular saturation pulse. Amide proton transfer-weighted (APTw) and GlycoCEST signals were quantified with the asymmetric magnetization transfer ratio (MTRasym) at 3.5 ppm and the total MTRasym integrated from 0.5 to 1.5 ppm from the corrected Z-spectrum, respectively. To explore scan time reduction, CEST images were reconstructed using 31 offsets (with 20 % time reduction) and 21 offsets (with 40 % time reduction), respectively. Results: For reproducibility, GlycoCEST measurements in 41 offsets showed the smallest scan-rescan mean measurements variability, indicated by the lowest mean difference of −0.049 % (95 % limits of agreement, −0.209 to 0.111 %); for APTw, the smallest mean difference was found to be 0.112 % (95 % limits of agreement, −0.698 to 0.921 %) in 41 offsets. Compared with after-meal, both GlycoCEST measurement and APTw measurement under different offset number decreased after 12-h fasting. However, as the offsets number decreased (41 offsets vs. 31 offsets vs. 21 offsets), GlycoCEST map and APTw map became more heterogeneous and noisier. Conclusion: Our results show that CEST liver imaging at 3.0 T has high sensitivity for fasting.
AB - Purpose: This study seeks to explore whether chemical exchange saturation transfer (CEST) magnetic resonance imaging (MRI) can detect liver composition changes between after-meal and over-night-fast statuses. Procedures: Fifteen healthy volunteers were scanned on a 3.0-T human MRI scanner in the evening 1.5–2 h after dinner and in the morning after over-night (12-h) fasting. Among them, seven volunteers were scanned twice to assess the scan–rescan reproducibility. Images were acquired at offsets (n = 41, increment = 0.25 ppm) from −5 to 5 ppm using a turbo spin echo (TSE) sequence with a continuous rectangular saturation pulse. Amide proton transfer-weighted (APTw) and GlycoCEST signals were quantified with the asymmetric magnetization transfer ratio (MTRasym) at 3.5 ppm and the total MTRasym integrated from 0.5 to 1.5 ppm from the corrected Z-spectrum, respectively. To explore scan time reduction, CEST images were reconstructed using 31 offsets (with 20 % time reduction) and 21 offsets (with 40 % time reduction), respectively. Results: For reproducibility, GlycoCEST measurements in 41 offsets showed the smallest scan-rescan mean measurements variability, indicated by the lowest mean difference of −0.049 % (95 % limits of agreement, −0.209 to 0.111 %); for APTw, the smallest mean difference was found to be 0.112 % (95 % limits of agreement, −0.698 to 0.921 %) in 41 offsets. Compared with after-meal, both GlycoCEST measurement and APTw measurement under different offset number decreased after 12-h fasting. However, as the offsets number decreased (41 offsets vs. 31 offsets vs. 21 offsets), GlycoCEST map and APTw map became more heterogeneous and noisier. Conclusion: Our results show that CEST liver imaging at 3.0 T has high sensitivity for fasting.
KW - Amide proton transfer (APT)
KW - Chemical exchange saturation transfer (CEST)
KW - Glycogen
KW - Liver
KW - Magnetic resonance imaging
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U2 - 10.1007/s11307-015-0887-8
DO - 10.1007/s11307-015-0887-8
M3 - Article
C2 - 26391991
AN - SCOPUS:84959920241
VL - 18
SP - 274
EP - 282
JO - Molecular Imaging and Biology
JF - Molecular Imaging and Biology
SN - 1536-1632
IS - 2
ER -