[Paper Review] Phantom model for intracranial pressure

Célia Batonon, Heimiri Monnier+2 more|arXiv (Cornell University)|Jan 21, 2026

Cerebrospinal fluid and hydrocephalus0 citations

TL;DR

This paper introduces MODÈFONE, a physical phantom of the cerebrospinal system that reproduces pulsatile ICP and allows gravity-variable experiments (including microgravity) via parabolic flights.

ABSTRACT

This report presents the MOD{È}FONE project, whose objective is to develop a simplified experimental model of the cerebrospinal system in order to investigate fluid-structure interactions and physiological adaptations under altered gravity conditions, with a particular focus on microgravity. The experimental setup is based on a pulsatile hydraulic circuit reproducing systolic and diastolic dynamics, coupled with deformable elements simulating vascular compliance and a cranial compartment immersed in a fluid representing cerebrospinal fluid. This model enables the analysis of cranial and spinal pressures as well as their pulsatility. The purpose of this report is to describe the design and the results of the experimental setup.

Motivation & Objective

• Develop a simplified physical model of the cerebrospinal system to study fluid–structure interactions under altered gravity.
• Incorporate pulsatile dynamics and vascular-like compliance into a craniospinal phantom.
• Enable measurements of mean and pulsatile ICP and spinal pressures under 1g, 1.8g, and 0g conditions.
• Validate the model against qualitative human ICP pulsatility and explore gravity-orientation effects.

Proposed method

• Construct a rigid cranial and compliant spinal phantom filled with water to simulate CSF.
• Couple the phantom to a pulsatile hydraulic circuit using a 12 V diaphragm pump to mimic cardiac-induced flow.
• Place a deformable latex segment in the spinal part to provide compliance and induce volume changes.
• Instrument with two pressure sensors and a triaxial accelerometer; synchronize data acquisition with pump control via a microcontroller.
• Use parabolic flights to vary gravity (1g, 1.8g, 0g) and phantom orientation (0°, 30°, 90°).
• Process data by estimating pump flow from control voltage, segmenting flight phases and cardiac cycles, and applying Savitzky–Golay filtering for pressure signals.

Experimental results

Research questions

• RQ1 How do gravity level and phantom orientation affect mean intracranial and spinal pressures?
• RQ2 How does gravity influence pulsatility and waveform morphology of ICP and spinal pressures in the phantom?
• RQ3 Can the phantom reproduce qualitative human ICP pulsatility patterns under different gravity conditions?

Key findings

• Mean ICP decreases with phantom orientation at 1g and 1.8g, with larger changes under hypergravity.
• Mean spinal pressure increases with phantom orientation under 1.8g, showing an opposing trend to ICP.
• ICP pulsatility is amplified in vertical orientation at 1g and 1.8g, but attenuated under 0g, with waveform morphologies shifting towards rounded peaks in microgravity.
• Under microgravity, pulsatility amplitudes decline for ICP in horizontal orientation and change distinctly in vertical orientation.
• Spinal pressure pulsatility remains generally high but shows orientation-related modifications differing from ICP.
• Qualitative comparisons suggest the phantom replicates several human ICP pulsatility features but lacks active regulatory mechanisms.