How growing tumour impacts intracranial pressure and deformation mechanics of brain

Ali Ahmed; Muhammad Uzair UlHaq; Zartasha Mustansar; Arslan Shaukat; Lee Margetts

doi:10.1098/rsos.210165

How growing tumour impacts intracranial pressure and deformation mechanics of brain

R Soc Open Sci. 2021 Sep 29;8(9):210165. doi: 10.1098/rsos.210165. eCollection 2021 Sep.

Authors

Ali Ahmed¹, Muhammad Uzair UlHaq¹, Zartasha Mustansar², Arslan Shaukat³, Lee Margetts⁴

Affiliations

¹ Department of Biomedical Engineering and Sciences, School of Mechanical and Manufacturing Engineering (SMME), National university of Sciences and Technology (NUST), Islamabad 44000, Pakistan.
² Department of Computational Engineering, Research Center of Modeling and Simulation (RCMS), National university of Sciences and Technology (NUST), Islamabad 44000, Pakistan.
³ Department of Computer and Software Engineering, College of Electrical and Mechanical Engineering, National university of Sciences and Technology (NUST), Islamabad 44000, Pakistan.
⁴ Department of Mechanical, Aerospace and Civil Engineering, University of Manchester, UK.

Abstract

Brain is an actuator for control and coordination. When a pathology arises in cranium, it may leave a degenerative, disfiguring and destabilizing impact on brain physiology. However, the leading consequences of the same may vary from case to case. Tumour, in this context, is a special type of pathology which deforms brain parenchyma permanently. From translational perspective, deformation mechanics and pressures, specifically the intracranial cerebral pressure (ICP) in a tumour-housed brain, have not been addressed holistically in literature. This is an important area to investigate in neuropathy prognosis. To address this, we aim to solve the pressure mystery in a tumour-based brain in this study and present a fairly workable methodology. Using image-based finite-element modelling, we reconstruct a tumour-based brain and probe resulting deformations and pressures (ICP). Tumour is grown by dilating the voxel region by 16 and 30 mm uniformly. Cumulatively three cases are studied including an existing stage of the tumour. Pressures of cerebrospinal fluid due to its flow inside the ventricle region are also provided to make the model anatomically realistic. Comparison of obtained results unequivocally shows that as the tumour region increases its area and size, deformation pattern changes extensively and spreads throughout the brain volume with a greater concentration in tumour vicinity. Second, we conclude that ICP pressures inside the cranium do increase substantially; however, they still remain under the normal values (15 mmHg). In the end, a correlation relationship of ICP mechanics and tumour is addressed. From a diagnostic purpose, this result also explains why generally a tumour in its initial stage does not show symptoms because the required ICP threshold has not been crossed. We finally conclude that even at low ICP values, substantial deformation progression inside the cranium is possible. This may result in plastic deformation, midline shift etc. in the brain.

Keywords: CSF; deformation; finite-element modelling; intracranial pressure; tumour.