Ultrashort Echo Time Bi-Component Analysis of Cortical Bone-A Field Dependence Study

作者：Li Shihong; Chang Eric Y; Bae Won C; Chung Christine B; Gao Song; Bao Shanglian; Bydder Graeme M; Hua Yanqing; Du Jiang^*

来源：Magnetic Resonance in Medicine, 2014, 71(3): 1075-1081.

DOI：10.1002/mrm.24769

• ultrashort TE
• T-2*
• bi-component analysis
• bound water
• free water

Purpose: The purpose of this study is to investigate the effect of differing field strength on the T-2* of cortical bone at 1.5 T and 3 T.
Methods: Ultrashort echo time pulse sequences were used to study six bovine and nine human bone samples at 1.5 T and 3 T using single- and bi-component T-2* analysis.
Results: On average, the bound water T-2* of bovine bone decreased by 16% (from 0.32 ms at 1.5 T to 0.27 ms at 3 T, P<0.01) and the bound water T-2* of human bone decreased by 21% (from 0.42 ms at 1.5 T to 0.33 ms at 3 T, P<0.01) at the higher field strength. The free water T-2* of bovine bone decreased by 50% (from 4.23 ms at 1.5 T to 2.12 ms at 3 T, P<0.001) and the free water T-2* of human bone decreased by 68% (from 7.65 ms at 1.5 T to 2.46 ms at 3 T, P<0.001) at the higher field strength. Bound and free water fractions showed only minor change with field strength in bovine (< 2%, P>0.05) and human bone (< 4%, P>0.05).
Conclusion: Ultrashort echo time bi-component analysis provides consistent bound and free water fractions at 1.5 T and 3 T, thereby allowing field-independent comparisons. Magn Reson Med 71:1075-1081, 2014.

• 出版日期2014-3
• 单位北京大学; 复旦大学