Quantitation of MRI sensitivity to quasi-monodisperse microbubble contrast agents for spatially resolved manometry.
Quantitation of MRI sensitivity to quasi-monodisperse microbubble contrast agents for spatially resolved manometry.
复制标题
定量 MRI 对准单分散微泡造影剂的敏感性，用于空间分辨测压。
DOI：
10.1002/mrm.24575
复制
发表时间：
2013
影响因子：
3.3
通讯作者：
Bencsik M
中科院分区：
文献类型：
--
作者：
Bencsik M
目的MRI无法实现液体压力的直接体内测量，除非使用造影剂。目前没有这样的造影剂可商购获得，而先前证明的那些造影剂由于其宽的尺寸分布而仅产生定性结果。我们的目的是定量然后建模的MR灵敏度存在的准单分散微泡population.MethodsLipid稳定的微泡人口的平均半径为1.2 ± 0.8 μm已产生的机械搅拌。形成了体积分数增加到4%的气泡的造影剂，并定量了气泡对弛豫率的贡献。一个周期性的压力变化也连续施加到相同的造影剂，直到MR信号的变化是由于气泡半径的变化，而不是由于气泡density.ResultsThe MR数据相比，有利的预测改进的数值模拟。一个优秀的MR灵敏度为23% bar-1已被证明。ConclusionThis work opened the possibility of generating microbubble preparations tailored to specific application with optimized MR sensitivity，特别是MRI为基础的体内测压。Magn Reson Med 70：1409-1418，2013年。© 2012 Wiley Periodicals，Inc.
PurposeThe direct in‐vivo measurement of fluid pressure cannot be achieved with MRI unless it is done with the contribution of a contrast agent. No such contrast agents are currently available commercially, whilst those demonstrated previously only produced qualitative results due to their broad size distribution. Our aim is to quantitate then model the MR sensitivity to the presence of quasi‐monodisperse microbubble populations.MethodsLipid stabilised microbubble populations with mean radius 1.2 ± 0.8 μm have been produced by mechanical agitation. Contrast agents with increasing volume fraction of bubbles up to 4% were formed and the contribution the bubbles bring to the relaxation rate was quantitated. A periodic pressure change was also continuously applied to the same contrast agent, until MR signal changes were only due to bubble radius change and not due to a change in bubble density.ResultsThe MR data compared favourably with the prediction of an improved numerical simulation. An excellent MR sensitivity of 23 % bar‐1has been demonstrated.ConclusionThis work opens up the possibility of generating microbubble preparations tailored to specific applications with optimised MR sensitivity, in particular MRI based in‐vivo manometry. Magn Reson Med 70:1409–1418, 2013. © 2012 Wiley Periodicals, Inc.