Investigating the stability of mcDESPOT myelin water fraction values derived using a stochastic region contraction approach.
Investigating the stability of mcDESPOT myelin water fraction values derived using a stochastic region contraction approach.
复制标题
DOI：
10.1002/mrm.25108
复制
发表时间：
2015-01
影响因子：
3.3
通讯作者：
Kolind SH
中科院分区：
文献类型：
--
作者：
Deoni SC;Kolind SH
T1和T2（mcDESPOT）的多组分驱动平衡单脉冲观测是一种替代建立多回波T2为基础的方法，用于量化髓鞘水分数，提供增加的体积覆盖范围和空间分辨率。然而，mcDESPOT的一个问题是必须估计大量的模型参数，这可能导致非唯一的解决方案和对拟合约束的敏感性。在这里，我们探讨mcDESPOT性能在不同的实验条件下，以更好地了解该方法的灵敏度和可靠性。为了获得参数估计值，mcDESPOT使用随机区域收缩（SRC）方法来迭代收缩全局最优值周围的预定义解搜索空间。mcDESPOT估计SRC边界条件和组织参数的灵敏度，使用数值幻影和体内人体数据采集进行了检查。SRC的方法进行了描述，并返回强大的髓鞘水估计在数值幻影和在体内的数据范围内的实验条件下。然而，在选择初始SRC边界条件时必须小心，确保它们足够宽以包含“真实”解。结果表明，在所考察的条件范围内，mcDESPOT能提供稳定、精确的测量值。
Multicomponent driven equilibrium single pulse observation of T1 and T2 (mcDESPOT) is an alternative to established multi-echo T2-based approaches for quantifying myelin water fraction, affording increased volumetric coverage and spatial resolution. A concern with mcDESPOT, however, is the large number of model parameters that must be estimated, which may lead to non-unique solutions and sensitivity to fitting constraints. Here we explore mcDESPOT performance under different experimental conditions to better understand the method’s sensitivity and reliability. To obtain parameter estimates, mcDESPOT uses a stochastic region contraction (SRC) approach to iteratively contract a pre-defined solution search-space around a global optimum. The sensitivity of mcDESPOT estimates to SRC boundary conditions, and tissue parameters, was examined using numerical phantoms and acquired in vivo human data. The SRC approach is described and shown to return robust myelin water estimates in both numerical phantoms and in vivo data under a range of experimental conditions. However, care must be taken in choosing the initial SRC boundary conditions, ensuring they are broad enough to encompass the ‘true’ solution. Results suggest that under the range of conditions examined, mcDESPOT can provide stabile and precise values.
登录
查看更多内容
影响因子：
2.5
作者：
MacKay, A;Laule, C;M채dler, B
通讯作者：
M채dler, B
影响因子：
3.3
作者：
Deoni, Sean C. L.;Rutt, Brian K.;Jones, Derek K.
通讯作者：
Jones, Derek K.
DOI：
10.1073/pnas.0910222107
发表时间：
2010-03-16
影响因子：
11.1
作者：
Lee, Jongho;Shmueli, Karin;Duyn, Jeff H.
通讯作者：
Duyn, Jeff H.
影响因子：
3.3
作者：
Gloor, M.;Scheffler, K.;Bieri, O.
通讯作者：
Bieri, O.
影响因子：
3.3
作者：
Levesque, Ives R.;Pike, G. Bruce
通讯作者：
Pike, G. Bruce