Fluid dynamic simulation for cellular damage due to lymphatic flow within the anatomical arrangement of the outer hair cells in the cochlea

• Published in: Computers in biology and medicine Vol. 161; p. 106986
• Main Authors: Yeom, Jiun, Park, Junseon, Park, Joong Yull
• Format: Journal Article
• Language: English
• Published: United States Elsevier Ltd 01.07.2023; Elsevier Limited
• Subjects: Boundary conditions; Cochlea; Computational fluid dynamics; Damage; Flow visualization; Fluid dynamics; Fluid flow; Hair; Hair cells; Hearing loss; Hearing protection; Hydrodynamics; Lymphatic flow; Mechanical stimuli; Numerical analysis; Outer hair cells; Physiology; Pressure; Sensory stimulation; Shear stress; Stem cells; Stereocilia; Stokes flow; Viscosity; Stereocilia; Cochlea; Flow visualization; Outer hair cells; Computational fluid dynamics; Lymphatic flow
• ISSN: 0010-4825; 1879-0534
• DOI: 10.1016/j.compbiomed.2023.106986

Damage to the sensory hair cells in the cochlea is a major cause of hearing loss since human sensory hair cells do not regenerate naturally after damage. As these sensory hair cells are exposed to a vibrating lymphatic environment, they may be affected by physical flow. It is known that the outer hair cells (OHCs) are physically more damaged by sound than the inner hair cells (IHCs). In this study, the lymphatic flow is compared using computational fluid dynamics (CFD) based on the arrangement of the OHCs, and the effects of such flow on the OHCs is analyzed. In addition, flow visualization is used to validate the Stokes flow. The Stokes flow behavior is attributed to the low Reynolds number, and the same behavior is observed even when the flow direction is reversed. When the distance between the rows of the OHCs is large, each row is independent, but when this distance is short, the flow change in each row influences the other rows. The stimulation caused by flow changes on the OHCs is confirmed through surface pressure and shear stress. The OHCs located at the base with a short distance between the rows receive excess hydrodynamic stimulation, and the tip of the V-shaped pattern receives an excess mechanical force. This study attempts to understand the contributions of lymphatic flow to OHC damage by quantitatively suggesting stimulation of the OHCs and is expected to contribute to the development of OHC regeneration technologies in the future. •Lymphatic flow in the cochlea is characterized by Stokes flow behavior.•Arrangement of the outer hair cells (OHCs) influences lymphatic flow changes.•Hydrodynamic forces are excessively applied to the V-shaped tips of OHCs.•Narrower row spacing between the OHCs produce greater forces on the stereocilia.