Analytical estimation of ultrasound properties, thermal diffusivity, and perfusion using magnetic resonance-guided focused ultrasound temperature data.
Analytical estimation of ultrasound properties, thermal diffusivity, and perfusion using magnetic resonance-guided focused ultrasound temperature data.
复制标题
DOI：
10.1088/0031-9155/61/2/923
复制
发表时间：
2016-01-21
影响因子：
3.5
通讯作者：
Payne A
中科院分区：
文献类型：
--
作者：
Dillon CR;Borasi G;Payne A
为了使热建模在磁共振引导聚焦超声（MRgFUS）热治疗的治疗计划、监测和控制中发挥重要作用，准确了解超声和热特性至关重要。本研究开发了一种新的分析解决方案，在MRgFUS中观察到的温度变化，可与实验MR温度数据一起使用，以提供超声初始加热速率，高斯波束方差，组织热扩散率和Pennes灌注参数的估计。模拟表明，该技术提供了准确和强大的属性估计，是独立的光束大小，热扩散率，和灌注水平的存在下，现实的MR噪声。该技术也证明在体内使用MRgFUS加热数据在兔背部肌肉。通过应用灌注项的三阶泰勒级数近似并确保拟合时间（用于优化的实验数据的持续时间）与灌注时间常数的比率保持小于1，使属性估计的误差保持小于5%。
For thermal modeling to play a significant role in treatment planning, monitoring, and control of magnetic resonance-guided focused ultrasound (MRgFUS) thermal therapies, accurate knowledge of ultrasound and thermal properties is essential. This study develops a new analytical solution for the temperature change observed in MRgFUS which can be used with experimental MR temperature data to provide estimates of the ultrasound initial heating rate, Gaussian beam variance, tissue thermal diffusivity, and Pennes perfusion parameter. Simulations demonstrate that this technique provides accurate and robust property estimates that are independent of the beam size, thermal diffusivity, and perfusion levels in the presence of realistic MR noise. The technique is also demonstrated in vivo using MRgFUS heating data in rabbit back muscle. Errors in property estimates are kept less than 5% by applying a third order Taylor series approximation of the perfusion term and ensuring the ratio of the fitting time (the duration of experimental data utilized for optimization) to the perfusion time constant remains less than one.