Needle Assembly with Retractable Cutting Edge for Lead Delivery

Solution Overview

Problem

Current medical devices face challenges in effectively tunneling through tissue to deliver stimulation leads to target sites within the body, particularly around vulnerable structures like the vagus nerve, where traditional methods risk causing trauma and distortion.

Innovation Solution

A needle assembly comprising an outer and inner needle, where the inner needle can transition between protracted and retracted positions, allowing for tissue cutting while minimizing exposure to vulnerable structures, is used to tunnel through tissue and deliver leads to target sites under ultrasound guidance.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Object-affected harmful factors

If a traditional needle is used to tunnel through tissue, then the needle can effectively cut tissue, but the needle tip is always exposed which may cause trauma to vulnerable structures

Engineering Contradiction:

Improvetissue traumaVSAvoidtissue cutting capability

Core Design Contradiction:

Object-affected harmful factorsVSEase of operation

Solution Approach 1:

The needle assembly employs a dynamic configuration where the inner needle can transition between retracted and protracted positions relative to the outer needle. This dynamic adjustment allows the cutting edge to be exposed only when needed for tunneling through tissue, and retracted when advancing near vulnerable structures, thereby resolving the contradiction between cutting capability and trauma prevention

Inventive Principle:

Principle #15Dynamics

Solution Approach 2:

The invention uses a nested structure with an inner needle containing a cutting edge positioned within the lumen of an outer needle. The inner needle can be extended beyond the outer needle's distal end when tissue cutting is required, and retracted into the outer needle when not in use or when approaching vulnerable structures, eliminating continuous exposure and potential trauma

Inventive Principle:

Principle #7Nested doll (Nesting)

2Productivity

If the inner needle is always extended to cut tissue, then tissue cutting is effective, but the cutting edge is continuously exposed which increases risk to vulnerable structures

Engineering Contradiction:

Improvetissue cutting efficiencyVSAvoidsafety near vulnerable structures

Core Design Contradiction:

ProductivityVSReliability

Solution Approach 1:

The needle assembly employs a dynamic configuration where the inner needle can transition between retracted and protracted positions relative to the outer needle. This dynamic adjustment allows the cutting edge to be exposed only when needed for tunneling through tissue, and retracted when advancing near vulnerable structures, thereby resolving the contradiction between cutting capability and trauma prevention

Inventive Principle:

Principle #15Dynamics

Solution Approach 2:

The cutting function is extracted as a separate, controllable element (the inner needle with cutting edge) that can be independently deployed only when needed. The inner needle can be extended beyond the outer needle's distal end when tissue cutting is required, and retracted into the outer needle when not in use or when approaching vulnerable structures, eliminating continuous exposure and potential trauma

Inventive Principle:

Principle #2Taking out (Extraction)

3Object-affected harmful factors

If the inner needle is retracted into the outer needle, then the cutting edge is protected from exposure, but the needle assembly cannot effectively cut tissue

Engineering Contradiction:

Improveexposure of cutting edgeVSAvoidtissue cutting ability

Core Design Contradiction:

Object-affected harmful factorsVSProductivity

Solution Approach 1:

The needle assembly employs a dynamic configuration where the inner needle can transition between retracted and protracted positions relative to the outer needle. This dynamic adjustment allows the cutting edge to be exposed only when needed for tunneling through tissue, and retracted when advancing near vulnerable structures, thereby resolving the contradiction between cutting capability and trauma prevention

Inventive Principle:

Principle #15Dynamics

Solution Approach 2:

The invention uses a nested structure with an inner needle containing a cutting edge positioned within the lumen of an outer needle. The inner needle can be extended beyond the outer needle's distal end when tissue cutting is required, and retracted into the outer needle when not in use or when approaching vulnerable structures, eliminating continuous exposure and potential trauma

Inventive Principle:

Principle #7Nested doll (Nesting)

Data Source

PatentUS10265097B2Needle assembly with retractable cutting edge

Publication Date: 2019.04.23 CARDIAC PACEMAKERS INC

AI summary

The disclosure relates to a needle assembly for delivering a lead and methods of use. The needle assembly is configured to cut tissue and reduce the potential for cutting vulnerable bodily structures. The needle assembly includes an outer needle with a blunt tip and an inner needle with a sharp tip. The outer needle may be curved, and the inner needle may be curved. When the inner needle is rotated with respect to the outer needle, the inner needle protracts or retracts with respect to the outer needle. A stopping feature on the needle assembly may be included to resist over-rotation or over-extension. The needle assembly provides an initial path that may be further dilated for delivering a lead, such as a vagus nerve stimulation lead to a target site. The target site may be electrically tested with some embodiments.