Session: 01-02: Micro/Nanofluidics and Lab-On-A-Chip

Paper Number: 132824

132824 - Thermal and Hemodynamic Characterization of Intracranial Aneurysm on Chip: A Numerical Investigation. 

Abstract: 

Intracranial aneurysms are localized dilations along the blood vessels of the cerebral artery. The rupture of these intracranial aneurysms leads to subarachnoid hemorrhage, which has a very high mortality rate throughout the world. Thus, the study of the hemodynamic parameters in an intracranial aneurysm is crucial for understanding the challenges associated with the treatment. Aneurysm-on-chip is a microfluidic chip that simulates typical aneurysm mechanics and physiological responses. The results of these studies are helpful for better and more effective diagnostics and treatments.

For hyperthermia and hypothermia patients, the temperature can vary from 41 °C to 32 °C, above and below which patients need medical emergency. The effect of the rise and fall of the blood temperature and the study on its impact on the viscosity are very limited for the flow behavior in the aneurysm. In the literature, researchers have considered the viscosity variation in terms of shear rate, either in the form of Newtonian or non-Newtonian models. Also, some researchers consider viscosity as a function of temperature. There are hardly any studies that consider viscosity as a function of both shear rate as well as temperature. We endeavor to formulate that and then verify that with existing results.

We use this viscosity model to investigate the effect of temperature on hemodynamics in an intracranial aneurysm-on-chip. A 3 mm spherical saccular intracranial aneurysm having an idealized geometry is considered on a 3 mm parent vessel artery as a preliminary investigation of the model for the aneurysm-on-chip. Ansys Fluent 18.1 software is used for the study, and a patient-specific velocity waveform is used at the inlet. A constant pressure is applied at the outlet. Three cases have been considered for the analysis purpose, correspondingly at normal body temperature, the temperature corresponding to a high-temperature limit for the hyperthermia patient, and the temperature corresponding to a low-temperature limit for the hypothermia patient that needs medical emergency. In this study, we look into the velocity contours on different planes and wall shear stress and see the implications of the effect of temperature on these aspects. In addition, we investigate on the vortex dynamics modes by flow visualization using the Q-criterion. This study will provide an idea of whether hyperthermia and hypothermia patients need special attention in cases of intracranial aneurysm.

Our future work is to establish a relationship between the aneurysm number, pulsatility index, vortex dynamics mode, the wall shear stress, and temperature in the saccular type intracranial aneurysm.

Presenting Author: Sumit Kumar National Institute of Technology Rourkela

Presenting Author Biography: N/A

Authors:

Gaurav Kumar National Institute of Technology Rourkela
Aneesh A. M. Birla Institute of Technology and Science- Pilani
Sumit Kumar National Institute of Technology Rourkela