An outline of continuum modeling of brain tissue mechanics

Modern, very sensitive, and noninvasive devices (strain-gauges, accelerometers, etc) detect deformations and motions in the order of a few microns. The observation that the rise in intracranial pressure produces measurable suture strain suggests that noninvasive determination of mechanical parameters in the intracranial cavity, such as density, velocity, pressure, energy, and their time rates, is clearly possible. Based on the above premise, and utilizing the concept of representative elementary volume (REV), this paper presents the conceptual part of a theory that defines the mechanical behavior of the brain and skull under various conditions. The systematic review of brain tissue mechanics leads to a continuum model of a mixed stress-displacement boundary value type, which defines the dynamics of the visco-elastic brain tissue in mathematical terms.