Comparative Analysis of Arterial and Choroid Plexus Oscillations on CSF Dynamics in Hydrocephalic Ventricles*

Objective Hydrocephalus treatment involves the implantation of a ventricular catheter (VC) into the ventricles to drain excess cerebrospinal fluid (CSF). This study compares the effects of CSF oscillations from arterial pulsations and choroid plexus secretions on CSF flow dynamics in shunted hydrocephalic ventricles of varying morphology.

Methods Deidentified, patient-specific MRI scans from Children's Hospital of Alabama were used to create 3D hydrocephalic ventricular models for computational fluid dynamics (CFD) simulation. Ventricular catheters were inserted into the lateral ventricles using anterior and posterior trajectories. Physiological boundary conditions, including CSF secretion from the choroid plexus, and fluid structure interaction (FSI) cardiac waveforms on the surface of the lateral ventricle were assigned with a constant pressure outlet at the VC exit. A laminar transient flow model analyzed fluid behavior in the drainage holes and lumen of the VC.

Results Simulation results showed no significant difference in CSF flow dynamics based on the source of oscillations, whether arterial pulsations or choroid plexus secretions. Both types of oscillations resulted in similar mass flow rates and shear stresses across ventricles of various sizes. Near-wall analysis indicated that ventricular size and proximity to the VC surface were more critical factors affecting eddy mixing and turbulent conditions than the type of CSF oscillation.

Conclusion The origin of CSF oscillations—whether arterial pulsations or choroid plexus secretions—does not significantly impact CSF flow dynamics in shunted hydrocephalic ventricles. These findings emphasize the importance of considering ventricular morphology and catheter placement over the specific oscillatory source when optimizing VC design and placement strategies. Personalized approaches to hydrocephalus treatment, considering these dynamics, can potentially improve patient outcomes by reducing VC failure rates.