Simulation And Modeling Research On The Relationship Between Intracranial Pressure And The Related Factors

Increased intracranial pressure (ICP) is caused by many diseases. Serious patients usually develop to cerebral hernia, even to death. So it is particularly important to understand the regulating mechanism of increased ICP and the influence the related facors taking to ICP. Only do this can we take timely and effective measures to decrease ICP. The essay studies the regulation mechanism of increased ICP and the relations between the various factors through mathematic modeling simulation method, and studies the relationship between ICP and brain hemodynamic parameters at the same time. Then puts forward a new ICP monitoring method. It provides a new means and methods for clinical noninvasive monitoring ICP.A simulation model of ICP, intracranial compliance(IC) and cerebrospinal fluid (CSF) outflow resistance (Ro) is discussed based on the previous of ICP mathematical models applying the theory of hemodynamics. So we get a further understanding of the ICP regulatory mechanism. Then we research the relationships between ICP, cerebral perfusion pressure(CPP) and hemodynamic parameters obtained by transcranial doppler(TCD). A new non-invasive ICP monitoring method is studied.Three researches are mainly done as follows:1. The research on the simulation model of the relationship between intracranial hypertension and cerebrospinal fluid circulation.Applying the principle and method of hemodynamics, we analyse the changes of ICP and models of cerebrospinal fluid circulation parameters. Then a mathematical model of ICP, IC and Ro is established based on the principle of constant total volume of cranial cavity. The study finds that ICP has a reverse correlating relationship with IC, and a positive correlating relationship with Ro. The model is consistent with some known medicinal conclusions. It provides a new idea for further study of cerebral blood flow automatic regulating mechanism under intracranial hypertension in pathological conditions.2. The research on the relationship between ICP and TCD parametersAs a non-invasive monitoring method, TCD receives more and more attention.The hemodynamic parameters observed from TCD have a close relationship with ICP. Through analysis of previous TCD parameters measured under intracranial hypertension condition, we establish a multivariate linear equation of ICP and TCD parameters. It is found that TCD parameters can express the changes of ICP very well. Then we establish a optimum regression equation, with a minimum variables. Finally the mean flow velocity (Vm) and pulsatility index (PI) are choosed. Through the simulation, it is found that the Vm and PI can estimate and predicte ICP perfectly. It provides a new way for clinical non-invasive ICP measurement.3. The clinical application of TCD parameters predicting ICPUsing clinical TCD parameters'datas, Vm is chosen for establishing the optimum regression equation through stepwise regression method. After simulation, it is found that Vm can forecast ICP's changes very well. It is a basic study for further clinical application.