Shunt Flusher Using Pressurized CSF Impulse Flow
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional back flushing methods in shunt systems for treating hydrocephalus are ineffective due to the limited amount of flushing fluid, which can lead to further clogging by rapid suction of cerebrospinal fluid, and often require surgical intervention for ventricular catheter obstructions.
Innovation Solution
A system that uses a reservoir to store and pressurize cerebrospinal fluid, which is then rapidly released to create an impulse flow to flush occlusions in the shunt catheter, including a secondary set of pores that can be opened if primary pores become blocked, and a valve mechanism to control fluid flow and prevent re-suction of blockages.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of operation
If conventional back flushing is used to clear occlusions in shunt catheters, then some flushing action is provided, but the limited amount of flushing fluid causes rapid suction of CSF back into the catheter, leading to more severe clogging
Solution Approach 1:
The system uses periodic action by implementing a controlled filling phase followed by a rapid discharge phase. The reservoir fills slowly with CSF over time, then rapidly discharges the accumulated fluid to create a high-velocity flush. This periodic cycle prevents continuous suction while delivering powerful periodic flushing action to clear occlusions without causing severe clogging.
Solution Approach 2:
The system applies preliminary action by accumulating flushing fluid in the reservoir before the actual flushing event. CSF is collected and stored in the reservoir during normal operation, then this pre-accomplished fluid is rapidly discharged when needed to create a high-velocity flush, eliminating the need for immediate fluid availability and preventing rapid suction during the flushing process.
2Reliability
If surgical revision is performed to remove obstructed ventricular catheters, then complete clearance of occlusions is achieved, but the procedure is complicated and carries risk of bleeding from choroid plexus avulsion
Solution Approach 1:
The system implements self-service by enabling the shunt system to clear its own occlusions through the reservoir-based flushing mechanism. The accumulated CSF in the reservoir automatically or manually triggers a flush that propels debris and occluding material out of the catheter pores, allowing the system to maintain itself without requiring surgical intervention and reducing the complexity of occlusion management.
Solution Approach 2:
The system applies the extraction principle by removing the obstructing material from the catheter lumen through the high-velocity flush. The rapid discharge of pressurized CSF extracts debris, choroid plexus fragments, and other occluding substances from the catheter pores and transports them away through the distal end, clearing the obstruction without surgical removal of the catheter.
3Ease of repair
If forceful removal of the catheter is attempted to clear choroid plexus obstruction, then the catheter can be replaced, but bleeding is caused by avulsion of choroid plexus
Solution Approach 1:
The system converts the harmful effect of choroid plexus obstruction into a beneficial flushing action. The occluding material itself, when exposed to the high-velocity CSF jet, becomes part of the flushed mixture that propels debris out of the catheter. The force that could cause damage is redirected to clear the obstruction safely, eliminating the need for forceful catheter removal and associated bleeding risks.
4Productivity
If a larger amount of flushing fluid is used in the reservoir, then more effective flushing can be achieved, but the device size and complexity increase
Solution Approach 1:
The system applies parameter changes by transforming the pressure parameter of the flushing fluid. Instead of increasing volume, the reservoir accumulates CSF and builds up pressure over time during the filling phase. This pressurized fluid is then discharged rapidly, creating a high-velocity jet that achieves effective flushing with a relatively small reservoir volume, maintaining productivity while controlling device size.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The system effectively clears occlusions in shunt catheters by using a pressurized impulse flow to push blockages away from the catheter pores, reducing the risk of re-clogging and allowing for non-surgical management of shunt obstructions, thereby improving the efficiency of shunt system maintenance.
Implementation Method 1
The reservoir is constructed and arranged to allow fluid therein to be pressurized whereby the fluid is rapidly released from the flow passage producing an impulse flow to flush the catheter
Implementation Method 2
the fluid is rapidly released from the flow passage producing an impulse flow to flush the catheter
Data Source
AI summary
A device and system for flushing a shunt catheter utilizes the available cerebrospinal fluid (CSF) to flush a blocked catheter. The CSF is pressurized to a predetermined amount and then allowed to suddenly, rapidly and forcefully purge any occlusions. The rapid release of CSF produces flow jets from the catheter pores into the ventricle. This impulse, or “cough”, will push and divert choroid plexus and/or other blockages away from the pores. The device and system may then be allowed to refill at a slow rate, thus reducing the possibility of rapid suction of fluid back into the system and the attendant possibility of drawing the choroid plexus back into the pores. The catheter at the proximal end may also include back-up pores that can be opened to restart flow from the ventricle should the primary pores remain blocked after a flushing attempt.