Putluru Deshik Reddy, Tepole Adrian Buganza, Gomez Hector
School of Mechanical Engineering, Purdue University, 585 Purdue Mall, West Lafayette, 47906, IN, USA.
Weldon School of Biomedical Engineering, Purdue University, 206 S Martin Jischke Dr, West Lafayette, 47906, IN, USA.
Fluids Barriers CNS. 2025 Jul 30;22(1):81. doi: 10.1186/s12987-025-00691-4.
Cerebrospinal flow dynamics (CSF) plays a critical role in structural disorders of the central nervous system (CNS) and in the design of effective procedures for intrathecal drug delivery. Medical imaging techniques have only partially characterized CSF dynamics. Computational models have the potential to offer a high-resolution description of CSF flow and advance our mechanistic understanding. However, anatomically-accurate computational models of CSF dynamics in the spinal canal have largely ignored the compliance of the spinal tissues, which is critical to understand the pulse wave velocity and the craniocaudal decay of CSF pulsations. Here, we propose a mixed-dimensional fluid-structure interaction method that enables high-fidelity simulations of CSF dynamics on anatomically-accurate models of the spinal canal, considering the tissue compliance effects emerging from the dura mater and epidural fat. Our mixed-dimensional approach bypasses a critical computational bottleneck that emerges from the multiscale geometry of spinal tissues. Our results show that accurate modeling of tissue compliance is critical to capture key elements of CSF dynamics. This work opens new possibilities to control and optimize intrathecal drug delivery and to understand structural abnormalities of the CNS.
脑脊液流动动力学（CSF）在中枢神经系统（CNS）的结构紊乱以及鞘内药物递送有效程序的设计中起着关键作用。医学成像技术仅部分表征了脑脊液动力学。计算模型有潜力提供脑脊液流动的高分辨率描述，并推进我们的机理理解。然而，椎管内脑脊液动力学的解剖学精确计算模型在很大程度上忽略了脊髓组织的顺应性，而这对于理解脑脊液搏动的脉搏波速度和头尾向衰减至关重要。在此，我们提出一种混合维度的流固相互作用方法，该方法能够在考虑到由硬脑膜和硬膜外脂肪产生的组织顺应性影响的情况下，对椎管的解剖学精确模型上的脑脊液动力学进行高保真模拟。我们的混合维度方法绕过了由脊髓组织的多尺度几何结构产生的关键计算瓶颈。我们的结果表明，组织顺应性的精确建模对于捕捉脑脊液动力学的关键要素至关重要。这项工作为控制和优化鞘内药物递送以及理解中枢神经系统的结构异常开辟了新的可能性。
