Biopsy Marker Delivery Device with Gradient Push Rod
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing biopsy site marking technologies face challenges in securely deploying markers without excessive force and ensuring they do not unintentionally fall out of the deployer, particularly in the context of biopsy devices.
Innovation Solution
A marker delivery device with a cannula having a side opening and a push rod system, where the push rod is rigid enough to deploy markers through a radiopaque marker engaging element and ramp, ensuring secure retention until intentional deployment, and is flexible to navigate through the cannula without lodging issues.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the push rod is made rigid to deploy markers through the radiopaque marker engaging element and ramp, then secure retention and controlled deployment of markers is achieved, but the push rod may lodge or fail to navigate through the cannula
Solution Approach 1:
The push rod is designed with varying mechanical properties along its length or in different sections. The proximal portion (near the operator) has higher rigidity to provide leverage for deploying the marker, while the distal portion (near the tip) has lower rigidity to allow flexible navigation through the cannula curvature. This local differentiation of mechanical properties resolves the contradiction between needing rigidity for marker deployment and flexibility for navigation.
2Ease of operation
If the push rod is made flexible to navigate through the cannula, then smooth operation is achieved, but the push rod cannot deploy markers through the radiopaque marker engaging element and ramp with sufficient force
Solution Approach 1:
The push rod incorporates a gradient of mechanical properties where the distal section is flexible to navigate the cannula's curvature without lodging, while the proximal section maintains sufficient rigidity to transmit deployment force to the marker. This localized differentiation allows the single push rod component to satisfy both contradictory requirements of flexibility for navigation and rigidity for force transmission.
3Reliability
If markers are securely retained in the deployer, then unintentional marker release is prevented, but excessive force is required to deploy the marker
Solution Approach 1:
The marker retention mechanism transitions from a static high-retention state during delivery to a dynamic release state during deployment. The radiopaque marker engaging element is designed with a retention geometry that holds the marker securely during navigation, but includes a release feature (such as a ramp or cam mechanism) that, when actuated by the push rod, dynamically changes the retention geometry to allow controlled marker ejection with minimal force.
Solution Approach 2:
The marker is pre-positioned and pre-retained in the deployer during the delivery phase, allowing secure transport to the target site. The retention mechanism is designed to maintain this preliminary retained state until the precise moment of deployment, at which point the push rod actuates the release mechanism to transition the marker from retained to deployed state with controlled minimal force.
Data Source
AI summary
A biopsy device for delivering a biopsy marker (300) to a biopsy site is disclosed. The biopsy device can include a marker deployer (10) having a unitary endpiece (21) disposed in a distal end of a cannula (12). The distal endpiece can be a molded component which includes a distal tip (22), a marker deployment ramp (210), and a marker engaging element (240) that aids in retaining the marker in the cannula until the marker is meant to be deployed.