Abstract：Objective: To explore the difference of proton density fat fraction(PDFF) values measured by lumbar vertebra magnetic resonance imaging(MRI) under different field strengths of 1.5T and 3.0T. Materials and Methods: This study was approved by the institutional review board. After signing informed consent, 21 healthy volunteers were scanned within 4～6 h under 1.5T and 3.0T MRI scanners, respectively. Both conventional lumbar MRI sequences and iterative decomposition of water and fat with echo asymmetry and least-squares estimation quantitation sequence(IDEAL-IQ) were tested to provide lumbar vertebra PDFF. The volunteers ranged in age from 21 to 50, with an average age of 27.95±9.92. L1~L5 lumbar vertebral sites were analyzed using IDEAL-IQ sequence, and the fat fraction(FF) values of two groups obtained from 1.5T and 3.0T GE MR scanners were compared with each other. The FF values of vertebral bone marrows were measured on AW4.6 postprocessing workstation. Paired t-test analysis between the two groups was performed. Results: The difference of the FF values was not statistically significant. Paired sample t-test analysis showed 1.5T & 3.0T L1 vertebral body(t=1.58, P=0.13), 1.5T & 3.0T L2 vertebral body(t=-1.11, P=0.28), 1.5T & 3.0T L3 vertebral body(t=0.77, P=0.45), 1.5T & 3.0T L4 vertebral body(t=0.67, P=0.51), 1.5T & 3.0 L5 vertebral body(t=0.18, P=0.86). Conclusion: Using IDEAL-IQ sequence to estimate the lumbar vertebra fat fraction is feasible. It can provide reliable marrow fat quantification.
宋 宇，宋清伟，张 楠，刘爱连，苗延巍. 不同场强下磁共振IDEAL-IQ技术对腰椎椎体脂肪含量定量对比分析[J]. 中国临床医学影像杂志, 2019, 30(9): 656-659.
SONG Yu, SONG Qing-wei, ZHANG Nan, LIU Ai-lian, MIAO Yan-wei. Quantitative comparison and analysis of lumbar vertebral fat content by IDEAL-IQ under different field intensities. JOURNAL OF CHINA MEDICAL IMAGING, 2019, 30(9): 656-659.
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