MRI-Based Noninvasive Measurement of Intracranial Compliance from the Relationship Between Transcranial Blood and CSF Flows: Modeling Vs Direct Approach

Rong-Wen Tain¹, Noam Alperin¹

Intracranial compliance (ICC) determines the ability of the intracranial space to accommodate increase in volume (e.g., brain swelling) without a large increase in intracranial pressure. A recently proposed method derives ICC from the ratio of the intracranial volume and pressure changes that occur naturally with each heart beat. In this study, an RLC circuit model was used to quantify the effect of changes in ICC on the amplitude and phase of the CSF flow. We observed that changes in ICC predominantly affected the amplitude and less so the phase. This explains why phase based techniques are less sensitive than amplitude based approach.