Departments of Imaging Physics, The University of Texas M.D. Anderson Cancer Center, Houston, TX, USA.
Department of Computational and Applied Mathematics, Rice University, Houston, TX, USA.
Int J Hyperthermia. 2020 Dec;37(3):155-163. doi: 10.1080/02656736.2020.1845403.
Convective transport is an important phenomenon for nanomedicine delivery. We present an imaging-based approach to recover tissue properties that are significant in the accumulation of nanoparticles delivered systemic methods. The classical pharmacokinetic analysis develops governing equations for the particle transport from a first principle mass balance. Fundamentally, the governing equations for compartmental mass balance represent a spatially invariant mass transport between compartments and do not capture spatially variant convection phenomena. Further, the parameters recovered from this approach do not necessarily have direct meaning with respect to the governing equations for convective transport. In our approach, a framework is presented for directly measuring permeability in the sense of Darcy flow through porous tissue. Measurements from our approach are compared to an extended Tofts model as a control. We demonstrate that a pixel-wise iterative clustering algorithm may be applied to reduce the parameter space of the measurements. We show that measurements obtained from our approach are correlated with measurements obtained from the extended Tofts model control. These correlations demonstrate that the proposed approach contains similar information to an established compartmental model and may be useful in providing an alternative theoretical framework for parameterizing mathematical models for treatment planning and diagnostic studies involving nanomedicine where convection dominated effects are important.
对流传输是纳米医学输送的一个重要现象。我们提出了一种基于成像的方法来恢复组织特性，这些特性在系统方法输送的纳米粒子积累中非常重要。经典的药代动力学分析从质量平衡的第一原理出发，推导出粒子传输的控制方程。从根本上说，隔室质量平衡的控制方程表示隔室之间的空间不变质量传输，并且不能捕获空间变化的对流现象。此外，从这种方法中恢复的参数不一定与对流传输的控制方程有直接的意义。在我们的方法中，提出了一种直接测量通过多孔组织的达西流渗透率的框架。将我们的方法的测量值与扩展的 Tofts 模型进行比较作为对照。我们证明可以应用像素级迭代聚类算法来减小测量的参数空间。我们表明，从我们的方法获得的测量值与从扩展的 Tofts 模型对照获得的测量值相关。这些相关性表明，所提出的方法包含与既定隔室模型类似的信息，并且在为涉及对流主导效应很重要的纳米医学的治疗计划和诊断研究的数学模型参数化提供替代理论框架方面可能是有用的。
