14 - Monitoring of intracranial pressure and assessment of cerebrospinal fluid dynamics

Summary

The current range of clinical applications for cerebrospinal fluid (CSF) dynamics testing includes hydrocephalus, idiopathic intracranial hypertension, craniosynostosis, and traumatic brain injury. CSF dynamics depends on interaction between four components: CSF production, flow, absorption, and pulsations. The mathematical model of CSF pressure-volume compensation provides a theoretical basis for the differential diagnosis in hydrocephalus. Components of this model are identified in many clinical scenarios and are in use in clinical diagnostic procedures. In all pressure-volume testing techniques, parameters of model are estimated using various algorithms and various volume-adding techniques. Pulse amplitude of intracranial pressure (ICP) is synchronized with pulse amplitude of arterial pressure and the pulse amplitude of blood flow velocity in the middle cerebral artery. Pulse amplitude increases proportionally to mean CSF pressure during the infusion study. The resistance to CSF outflow demonstrates significant associations with cerebrovascular reactivity: patients with lower Rout tend to have more frequently disturbed cerebrovascular reactivity.