LaBS, Chemistry Materials and Chemical Engineering Department "Giulio Natta", Politecnico di Milano, Piazza L. da Vinci 32, 20133 Milan, Italy.
LaBS, Chemistry Materials and Chemical Engineering Department "Giulio Natta", Politecnico di Milano, Piazza L. da Vinci 32, 20133 Milan, Italy.
Med Eng Phys. 2020 Aug;82:49-57. doi: 10.1016/j.medengphy.2020.06.005. Epub 2020 Jul 8.
The purpose of this study is to investigate the effect of vitreous sloshing induced by saccades on the intravitreal delivery of large molecule drugs. The vitreous body was considered in its age-related liquefaction condition. Fluid dynamics and large molecule distribution were described by the coupling of mass conservation's and Fick's laws with continuity and momentum equations for a Newtonian incompressible fluid in a 3D unsteady analysis. Two injection sites were analyzed, in both the mixing effect of a 50° periodic saccade leads to uniform drug distribution in 30 s of simulation, the initial bolus site being left after 3 s of simulation. In absence of saccadic movements, the dominant transport contribution is the diffusive one and large molecules hardly reach their uniform distribution inside the vitreous cavity. A model describing the intravitreal distribution of large molecules in presence of saccades was developed, improving the understanding of drug transport mechanism after an intravitreal injection and highlighting how advection contribution enhances its distribution in the vitreous chamber.
本研究旨在探讨眼球跳动引起的玻璃体晃动对大分子药物玻璃体腔内递释的影响。玻璃体在其与年龄相关的液化状态下进行了考虑。通过质量守恒和菲克定律与牛顿不可压缩流体的连续和动量方程的耦合，对流体动力学和大分子分布进行了描述，进行了 3D 非稳态分析。分析了两个注射部位，在 50°周期性扫视的混合作用下，模拟 30 秒内导致药物均匀分布，模拟 3 秒后初始团注部位被排空。在没有扫视运动的情况下，主要的输运贡献是扩散，大分子很难在玻璃体腔内达到均匀分布。开发了一种描述有扫视时玻璃体中大分子分布的模型，该模型加深了对玻璃体内注射后药物输运机制的理解，并强调了对流贡献如何增强其在玻璃体腔内的分布。
