Magnetic resonance imaging phantoms for quality-control of myocardial T1 and ECV mapping: specific formulation, long-term stability and variation with heart rate and temperature
Magnetic resonance imaging phantoms for quality-control of myocardial T1 and ECV mapping: specific formulation, long-term stability and variation with heart rate and temperature
复制标题
用于心肌 T1 和 ECV 绘图质量控制的磁共振成像体模：特定配方、长期稳定性以及随心率和温度的变化
DOI：
--
复制
发表时间：
2016
影响因子：
6.4
通讯作者：
D. Firmin
中科院分区：
文献类型：
--
作者：
V. Vassiliou;E. Heng;P. Gatehouse;J. Donovan;C. Raphael;S. Giri;S. Babu;M. Gatzoulis;D. Pennell;S. Prasad;D. Firmin
背景磁共振成像（MRI）体模通常用于MRI中心的质量保证;然而，它们用于验证心肌T1/细胞外容积分数（ECV）图的长期稳定性从未被研究过。方法在可重复的实验室程序中配制氯化镍琼脂糖凝胶模型以模拟血液和心肌T1和T2值，T1/ECV标测中使用的钆给药后的天然和晚期。在12个月的时间里，以一种仔细控制的可重复的方式，每周对体模进行11次心搏的MOLLI序列（T1）和长TR自旋回波序列（T2）的成像。（T1值的最大相对变化高达9.0%）或体模ECV（ECV的最大相对变化高达8.3%，ECV的最大绝对变化高达2.2%）。温度敏感性测试显示，长T1体模中的MOLLI T1值每增加一度增加23.9 ms，短T1体模中的MOLLI T1值每增加一度增加0.3 ms。ECV有0.069%的小幅绝对增加（约0.22%的ECV相对增加）每度增加。心率测试的变化显示，0.13%的ECV绝对增加（ECV相对增加约0.45%）结论这是文献中报道的第一个专门为血液和心肌建模T1和T2值的模型用于T1标测/ECV标测应用，经过12个月的严格稳定性测试。这项工作具有重要意义的效用，这样的幻影在提高连续扫描的准确性，心肌组织特征的T1映射方法和多中心工作。
BackgroundMagnetic resonance imaging (MRI) phantoms are routinely used for quality assurance in MRI centres; however their long term stability for verification of myocardial T1/ extracellular volume fraction (ECV) mapping has never been investigated.MethodsNickel-chloride agarose gel phantoms were formulated in a reproducible laboratory procedure to mimic blood and myocardial T1 and T2 values, native and late after Gadolinium administration as used in T1/ECV mapping. The phantoms were imaged weekly with an 11 heart beat MOLLI sequence for T1 and long TR spin-echo sequences for T2, in a carefully controlled reproducible manner for 12 months.ResultsThere were only small relative changes seen in all the native and post gadolinium T1 values (up to 9.0 % maximal relative change in T1 values) or phantom ECV (up to 8.3 % maximal relative change of ECV, up to 2.2 % maximal absolute change in ECV) during this period. All native and post gadolinium T2 values remained stable over time with <2 % change.Temperature sensitivity testing showed MOLLI T1 values in the long T1 phantoms increasing by 23.9 ms per degree increase and short T1 phantoms increasing by 0.3 ms per degree increase. There was a small absolute increase in ECV of 0.069 % (~0.22 % relative increase in ECV) per degree increase.Variation in heart rate testing showed a 0.13 % absolute increase in ECV (~0.45 % relative increase in ECV) per 10 heart rate increase.ConclusionsThese are the first phantoms reported in the literature modeling T1 and T2 values for blood and myocardium specifically for the T1mapping/ECV mapping application, with stability tested rigorously over a 12 month period. This work has significant implications for the utility of such phantoms in improving the accuracy of serial scans for myocardial tissue characterisation by T1 mapping methods and in multicentre work.
影响因子：
14
作者：
Kali, Avinash;Choi, Eui-Young;Dharmakumar, Rohan
通讯作者：
Dharmakumar, Rohan