摘要
目的:对附加水激发技术的3D-FLASH序列进行优化,并与传统的频率预饱和脂肪抑制技术的3D-FLASH序列进行比较。方法:健康成年志愿者10人,扫描序列采用不同的脉冲重复时间(TR)、回波时间(TE)和翻转角度(FA)的3组3D-WE-FLASH序列和一组3D-FS-FLASH序列。在各扫描序列标准矢状位图像上测量膝关节软骨信噪比(SNR)、关节软骨与周围组织之间的对比度噪声比(CNR)和关节软骨与关节液体之间的对比度噪声比效率(CNRca-fluidefficiency)。采用重复测量资料的方差分析对量化数据进行分析。结果:SNRca,CNRca-fluid,CNRca-bone,CNRca-fat,CNRca-menisus在序列4组均显著性高于序列1、2、3组;SNRca,CNRca-fluid,CNRca-fat,CNRca-bone在序列2组显著性高于序列1、3组;CNRca-fluideff在序列2、4组之间无显著性差异。结论:经优化后的水激发3D-FLASH序列能够显著缩短扫描时间并达到理想的软骨成像效果。
Objective To optimize a rapid cartilage dedicated 3D-FLASH sequence using water excitation instead of conventional spectral fat suppression and compare the value of 3D-WE-FLASH sequence with 3D-FS-FLASH on evaluating articular hyaline cartilage of knee in 10 healthy volunteers. Methods. The knees of ten volunteers were scanned at 1.5T by using sagittal 3D-WE-FLASH and 3D-FS-FLASH ,and different repetition time（TR）, echo time（TE）, or flip angle（FA） were adoped in 3D-WE-FLASH sequence. The signal noise ratio of cartilage was calculated.Then the contrast noise ratio between cartilage and its surrounding tissues, and contrast noise ratio efficiency between cartilage and fluid were calculated to quantitatively analyze the various sequences. Quantitative results were evaluated with repeated measures ANOVA. Results Group 4 had a significantly higher SNRca, CNRca-fluid, CNRca-b CNRca_fat, CNRea.menisus than in the group 1, 2, 3. Group 2 had a significantly higher SNPca, CNRca-fluid, CNRca-fat, CNRca-bone than group 1, 3. Group 4 had a significantly higher CNRca-fiuid eft than group 1,3,and there is no differert with CNRca-fluia eff between group2,4.Conclusion 3D-WE-FLASH sequence which had been optimized is valid for short acquisition time and hyaline cartilage visualization.
出处
《CT理论与应用研究（中英文）》
2009年第3期79-84,共6页
Computerized Tomography Theory and Applications
关键词
核磁共振成像
关节软骨
膝关节
magnetic resonance imaging
cartilage
knee joint
