Geometrical Vitality of Human Head model to Calculate Intra Cranial Pressure for Procognitive Computing

Abstract

Developing geometries of the real objects using computer aided engineering methods has been a common practice now. However, due to the evolution of advancement and launch of digital age, there is a recent interest to develop refined, smooth and entirely significant geometrical details to account for accuracy in predictions. Whether it is a scientific computation or reverse engineering, simulation or geometrical reconstruction; data sets with delicate geometric details are created quite often for various purposes. The usefulness of such geometric details rests on the ability to process them efficiently i.e. from digital models to numerical models and eventually for high-end visualization data analysis. In the field of biomedical engineering, geometry plays a very important role in model prediction. This study therefore considers the significance of geometry in the human head model to calculate critical pressure in the brain named “Intra-Cranial Pressure”. Elevated intracranial pressure (ICP) is one of the common consequences of traumatic conditions and has a profound influence on outcome. There are well established methods for the measurement, continuous monitoring and treatment of raised ICP. However, there is a need to build computer models for the same for validation and prediction. We made use of a tumour brain, in this study to see how geometry varies the values acquired for ICP in the brain. One of the major benefits of this study will be non-invasive computation of pressure inside the brain in a safe frequency range. It is well established that the relation between volume and pressure is non-linear. Additionally, skull is usually, considered as an enclosed and in-elastic container like a sac. The positioning of layers within this sac generates a constant pressure which is normal according to the body homeostasis. An increase in the volume of any of the intra cranial contents (Sac contents) is naturally offset by a decrease in pressure in one or the other content in it. However, when the size of the tumor (which is not an intracranial content) increases, the compensatory mechanisms gets exhausted and further increase in the brain sac in terms of volume results in an extremely elevated ICP. This mechanism is replicated in this research by using two approaches based on geometry: (i) Simple Geometry using Image based Finite Element modeling (ii) A regular engineering geometry using CAD modeling in Abaqus CAE. Reportedly the normal range of ICP lies between 3.75~15mmHg in humans. We have generated two head models with these approaches using the same boundary conditions and loading parameters.