Elucidating iIntracranial Fluid dDynamics and Intracranial Elasticity

Background: Traumatic Brain Injury (TBI) results in brain tissue edema and constricted fluid pathways. Since CSF production continues, it may lead to fluid accumulation, resulting in elevated intracranial pressure (ICP) and intracranial elasticity. ICP is continuously monitored, however it is not a specific measure for edema severity. Understanding the complex normal and pathological fluid dynamics in the cranium following TBI and obtaining intracranial elasticity measurements may help develop tools for better TBI patients management.

Methods: Analog circuits, representing lumped-parameter fluid dynamics in the brain, were developed. Simulations of the complex interactions in the cranium both in healthy and hydrocephalic conditions were conducted. In addition, an animal experimental model was developed and trials were conducted on pigs. Data acquired in a pig disease model was analyzed and intracranial elasticity was calculated in normal and induced hydrocephalus pathology conditions.

Results: The model reproduced the physiological and pathological behavior of intracranial fluids, affecting ICP and intracranial elasticity. Induced pathology in the mathematical model resulted in increased ICP and high intracranial elasticity. Animal trials data analysis showed an increase in intracranial elasticity with ICP elevation.

Conclusion: The computational model and animal trials described intracranial interactions occurring with hydrocephalus in a physiologically compatible manner. The ability of continuous intracranial elasticity calculation from the physiological data demonstrated the usefulness of this parameter in TBI patients management.