Expandable Percutaneous Sheath Balloon Tract Formation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current percutaneous nephrostomy systems face challenges in creating a minimally invasive access pathway with a small diameter tissue tract that can accommodate larger diameter instruments, often requiring multiple steps and angular shearing forces, which can be traumatic and inefficient.
Innovation Solution
A percutaneous access system featuring an expandable access sheath with a tubular body that transitions from a smaller to a larger cross-sectional profile, utilizing a releasable jacket and an expandable member, such as a balloon, to facilitate instrument passage while minimizing tissue trauma and procedural complexity.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a stiff guidewire and sequential dilators are used to create the tract, then a working lumen is established, but angular shearing forces are applied to the tissue causing trauma and requiring multiple steps
Solution Approach 1:
The patent uses a balloon catheter inflated with fluid to dilate the tissue tract. The balloon is advanced over the guidewire and inflated to expand the tract to the desired diameter, replacing the mechanical sequential dilator system with a pneumatic/hydraulic expansion method that reduces angular shearing forces and tissue trauma.
Solution Approach 2:
The patent employs a compliant sheath that can dynamically change its cross-sectional area. The sheath is collapsed to a small profile for insertion through the skin and guidewire, then expanded to a larger working diameter once positioned, allowing smooth tract formation without rigid angular shearing forces.
2Reliability
If sequential dilators and sheaths are advanced to create the tract, then access is achieved, but multiple procedural steps are required reducing efficiency
Solution Approach 1:
The patent combines the guidewire, balloon catheter, and sheath into a single integrated assembly that can be inserted through one puncture site. The guidewire provides tracking, the balloon creates the tract, and the sheath maintains access, eliminating the need for multiple separate dilator and sheath placement steps.
Solution Approach 2:
The sheath is pre-assembled with the balloon catheter and guidewire in a ready-to-deploy configuration. Once the balloon is inflated to create the tract, the sheath is already in position to immediately provide access, eliminating the need for sequential placement of multiple components.
3Object-affected harmful factors
If a small diameter puncture is made to minimize invasiveness, then patient trauma is reduced, but accommodating larger instruments becomes difficult
Solution Approach 1:
The sheath is designed with dynamic expandability, transitioning from a collapsed small-profile state during insertion to an expanded large-diameter state for instrument access. This allows the puncture site to remain small and minimally invasive while the sheath interior provides ample space for larger instruments when needed.
Solution Approach 2:
The balloon catheter is nested within the sheath, and both are advanced over the guidewire in a nested configuration. The balloon expands within the sheath to dilate the tract, creating space for instruments while the sheath itself remains contained within the small puncture site.
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 enables minimally invasive access with reduced tissue trauma and procedural steps, allowing for the passage of larger instruments through a small diameter tract, enhancing the efficiency and safety of procedures like percutaneous nephrostomy.
Implementation Method 1
at least a portion of the elongate tubular body is expandable from a first, folded, smaller cross-sectional profile to a second, greater cross-sectional profile
Data Source
AI summary
Disclosed is an expandable percutaneous sheath, for introduction into the body while in a first, low cross-sectional area configuration, and subsequent expansion to a second, enlarged cross-sectional configuration. The sheath is maintained in the first, low cross-sectional configuration by a tubular restraint. In one application, the sheath is utilized to provide access for a diagnostic or therapeutic procedure such as percutaneous nephrostomy or urinary bladder access.