Passive Endoscopic Suture Cutter for Tortuous Channel Navigation

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Existing endoscopic suture cutters with manually movable blades are difficult to navigate through flexible insertion tubes due to their long rigid distal ends, especially when the tube forms a tortuous path, and require active control, making them cumbersome and inefficient.

Innovation Solution

A suture cutter with a passive cutting mechanism that uses a drive wire to extend and retract through the insertion tube, featuring a cutter with a proximally-facing suture receiving portion and non-moving blades that cut the suture by applying tension, allowing for easy navigation and deployment.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Ease of operation

If traditional endoscopic scissors with manually movable blades are used, then cutting function is achieved, but navigation through flexible insertion tubes becomes difficult due to long rigid distal ends

Engineering Contradiction:

Improvenavigation through insertion tubeVSAvoidrigid longitudinal traversal length

Core Design Contradiction:

Ease of operationVSLength of moving object

Solution Approach 1:

The cutter is segmented into a rigid cutting portion and a flexible connection portion, allowing the rigid part to be short for easy navigation while the flexible part provides the necessary cutting functionality. The rigid longitudinal traversal length L is reduced to less than about 8 mm, preferably less than 5 mm, by separating the rigid cutting elements from the flexible drive mechanism.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

Instead of pushing the cutter forward to engage the suture, the cutter is designed to be pulled backward (proximally) to engage and cut the suture. The suture receiving portion faces proximally, and pulling the drive wire proximally causes the cutter to engage the suture and cut it by applying tension in the opposite direction of traditional scissors.

Inventive Principle:

Principle #13The other way round (Inversion)

2Ease of operation

If traditional scissors with manually movable blades are used, then cutting capability is provided, but device complexity increases due to active control requirements

Engineering Contradiction:

Improveoperational simplicityVSAvoidcontrol mechanism complexity

Core Design Contradiction:

Ease of operationVSDevice complexity

Solution Approach 1:

The cutter transitions from a static, manually controlled device to a dynamically actuated device driven by the flexible drive wire. The drive wire's flexing and pulling motions automatically engage and retract the cutter, eliminating the need for complex manual control mechanisms while providing precise cutting action.

Inventive Principle:

Principle #15Dynamics

Solution Approach 2:

The cutter is designed to be self-actuating through the mechanical coupling with the drive wire. As the drive wire is pulled proximally, it automatically engages the cutter with the suture and retracts it, making the cutting action self-service without requiring separate control mechanisms for blade movement and positioning.

Inventive Principle:

Principle #25Self-service

3Manufacturing precision

If the cutter has a longer rigid length for stability, then cutting precision improves, but maneuverability through angulated insertion tubes deteriorates

Engineering Contradiction:

Improvecutting precisionVSAvoidmaneuverability through angulated tubes

Core Design Contradiction:

Manufacturing precisionVSAdaptability or versatility

Solution Approach 1:

The cutter incorporates a flexible connection portion that acts as a flexible shell, allowing the rigid cutting portion to navigate through angulated insertion tubes while maintaining its structural integrity for precise cutting. The flexible portion bends to follow the tube's curvature, enabling the rigid cutter to reach the target location with precision.

Inventive Principle:

Principle #30Flexible shells and thin films

Solution Approach 2:

The rigid cutter with precise cutting edges is nested within the flexible drive wire structure. The rigid cutting portion (length L < 8 mm) is contained within or coupled to the flexible drive mechanism, allowing it to be guided through angulated tubes while maintaining its short, precise profile for accurate cutting operations.

Inventive Principle:

Principle #7Nested doll (Nesting)

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 cutter efficiently cuts sutures by pulling the drive wire proximally, reducing the risk of accidental tissue injury and improving maneuverability through flexible endoscope channels, even when angulated, thus enhancing surgical efficiency.

Implementation Method 1

Pulling the drive wire proximally applies tension to the suture using the cutter, particularly one or more sharp edges of the cutter.

Methodology Applied

Scientific EffectTension: Tension

Implementation Method 2

The suture is then cut by pulling the drive wire proximally.

Methodology Applied

Scientific EffectMechanical Force: Mechanical Force

Data Source

PatentUS12569244B2Endoscopic suture cutter

Publication Date: 2026.03.10 ENVISION ENDOSCOPY INC

AI summary

A method is used to cut a suture. The method provides a drive wire coupled with a cutter. The cutter has a first blade defining a first plane, and a second blade defining a second plane that is non-parallel with the first plane. The first blade and the second blade define an opening. The method hooks a suture into the opening. The method cuts the suture by pulling the drive wire in a proximal direction.