Stent Pusher Assembly Minimizing Ureteral Irritation

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing ureteral stent placement methods can cause irritation to patients due to the bladder fixing portion entering the ureteral passageway, leading to discomfort and potential complications.

Innovation Solution

A stent pusher assembly with an inner and outer pusher, guided by a wire, positions the ureteral stent in the kidney and bladder without entering the ureteral passageway, using a tether system to secure the stent in place and minimize irritation.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If the bladder fixing portion of the stent enters the ureteral passageway for secure placement, then the stent can be reliably retained in the bladder, but it causes irritation to the patient and potential complications

Engineering Contradiction:
Improvestent retentionVSAvoidpatient irritation
Core Design Contradiction:
ReliabilityVSObject-affected harmful factors

Solution Approach 1:

The patent extracts the bladder fixing portion from the ureteral passageway by using a pusher assembly that delivers the stent through the passageway without the fixing portion making contact with the ureteral wall. The pusher assembly acts as an intermediary that carries the stent to the bladder and releases it there, preventing the fixing portion from entering and irritating the ureteral passageway while still achieving reliable bladder retention.

Inventive Principle:
Principle #2Taking out (Extraction)

Solution Approach 2:

The pusher assembly serves as an intermediary device between the operator and the stent. It facilitates the delivery of the stent through the ureteral passageway and into the bladder, then releases the stent for proper positioning. This intermediary mechanism allows the stent to be securely retained in the bladder without the fixing portion directly contacting or entering the ureteral passageway, thereby eliminating patient irritation.

Inventive Principle:
Principle #24Intermediary (Mediator)

2Ease of operation

If a traditional pusher assembly is used to position the stent, then the stent can be advanced through the ureteral passageway, but the assembly structure becomes complex with multiple components

Engineering Contradiction:
Improvestent positioningVSAvoidpusher assembly structure
Core Design Contradiction:
Ease of operationVSDevice complexity

Solution Approach 1:

The pusher assembly is segmented into distinct functional components: an outer pusher for advancing the stent through the ureteral passageway, an inner pusher for positioning the stent within the bladder, and a release mechanism. This segmentation allows each component to perform its specific function independently, simplifying the overall operation while maintaining ease of stent positioning. The modular design reduces complexity compared to traditional single-piece pushers.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The pusher assembly incorporates dynamic elements including a movable inner pusher that can be advanced independently within the outer pusher, and a release mechanism that transitions from a constrained state during delivery to a free state for positioning. This dynamic capability allows the assembly to adapt to different anatomical conditions and provides precise control over stent placement, improving ease of operation without requiring overly complex structural elements.

Inventive Principle:
Principle #15Dynamics

Data Source

PatentEP2858709B1Stent pusher assembly
Publication Date: 2021.04.21 UNIV HOSPITALS HEALTH SYST
  • EP2858709B1 patent drawingFigure 1
  • EP2858709B1 patent drawingFigure 2
  • EP2858709B1 patent drawingFigure 3

AI summary

Provided is a stent pusher assembly (100) for positioning a ureteral stent (50), the stent pusher assembly having an inner (102) and outer stent pusher (104). The stent pusher assembly positions the ureteral stent in a patient's kidney and bladder without a bladder fixing portion (52) of the stent entering a ureteral passageway, thereby minimizing irritation to the patient.