School of Mechanical & Aerospace Engineering, Jilin University, 5988 Renmin Street, Changchun, 130025, People's Republic of China.
Key Laboratory of CNC Equipment Reliability, Ministry of Education, Jilin University, 5988 Renmin Street, Changchun, 130025, People's Republic of China.
Biomech Model Mechanobiol. 2024 Feb;23(1):241-254. doi: 10.1007/s10237-023-01771-w. Epub 2023 Oct 20.
Pulsed electric fields are extensively utilized in clinical treatments, such as subthalamic deep brain stimulation, where electric field loading is in direct contact with brain tissue. However, the alterations in brain tissue's mechanical properties and microstructure due to changes in electric field parameters have not received adequate attention. In this study, the mechanical properties and microstructure of the brain tissue under pulsed electric fields were focused on. Herein, a custom indentation device was equipped with a module for electric field loading. Parameters such as pulse amplitude and frequency were adjusted. The results demonstrated that following an indentation process lasting 5 s and reaching a depth of 1000 μm, and a relaxation process of 175 s, the average shear modulus of brain tissue was reduced, and viscosity decreased. At the same amplitude, high-frequency pulsed electric fields had a smaller effect on brain tissue than low-frequency ones. Furthermore, pulsed electric fields induced cell polarization and reduced the proteoglycan concentration in brain tissue. As pulse frequency increased, cell polarization diminished, and proteoglycan concentration decreased significantly. High-frequency pulsed electric fields applied to brain tissue were found to reduce impedance fluctuation amplitude. This study revealed the effect of pulsed electric fields on the mechanical properties and microstructure of ex vivo brain tissue, providing essential information to promote the advancement of brain tissue electrotherapy in clinical settings.
脉冲电场被广泛应用于临床治疗中，如丘脑底核深部脑刺激术，其中电场加载与脑组织直接接触。然而，电场参数变化导致的脑组织机械性能和微观结构的改变尚未得到足够的重视。本研究聚焦于脉冲电场下脑组织的机械性能和微观结构。为此，我们设计了一种定制的压痕装置，并配备了电场加载模块，可以调整脉冲幅度和频率等参数。结果表明，在 5s 的压痕过程和 1000μm 的深度后，经过 175s 的松弛过程，脑组织的平均剪切模量降低，粘度降低。在相同幅度下，高频脉冲电场对脑组织的影响小于低频电场。此外，脉冲电场诱导细胞极化并降低脑组织中蛋白聚糖的浓度。随着脉冲频率的增加，细胞极化减弱，蛋白聚糖浓度显著降低。高频脉冲电场作用于脑组织时，发现其阻抗波动幅度减小。本研究揭示了脉冲电场对离体脑组织机械性能和微观结构的影响，为促进临床脑组织电疗的发展提供了重要信息。
