Computational and experimental study of proximal flow in ventricular catheters. Technical note

Area of Science:

• Biomedical Engineering
• Fluid Dynamics
• Neurosurgery

Background:

• Hydrocephalus treatment frequently involves shunt insertion, which has high failure rates.
• Blockages in ventricular catheters, particularly at proximal holes, are a primary cause of shunt failure.

Purpose of the Study:

• To investigate the fluid dynamics of ventricular catheter designs.
• To identify the specific locations of catheter blockage.
• To develop and test improved catheter designs to reduce failure rates.

Main Methods:

• Computational fluid dynamics (CFD) modeling to simulate fluid flow.
• Two-dimensional water table experiments.
• Three-dimensional (3D) automated testing apparatus with actual catheters and ink visualization.

Main Results:

• CFD analysis revealed that over 58% of fluid mass enters the most proximal holes, with over 80% entering the two most proximal sets in an eight-hole catheter.
• Experimental verification confirmed that most fluid enters proximal holes, leading to blockages and complete catheter failure.
• New designs with variable hole distributions and sizes significantly altered flow distribution, promoting more uniform entry.

Conclusions:

• The majority of fluid entering ventricular catheters concentrates at the proximal holes, leading to frequent blockages and shunt failure.
• Novel ventricular catheter designs featuring variable proximal hole diameters promote more uniform fluid entry along the catheter length.
• These design modifications effectively reduce the probability of catheter occlusion, potentially improving hydrocephalus treatment outcomes.