Self-Expanding Nitinol Device for Stroke Recanalization

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Current revascularization systems for acute stroke treatment, such as clot retrievers and stents, have limited success in restoring blood flow, with high rates of hemorrhage, reocclusions, and complications due to high-pressure balloon angioplasty and distal wire perforation, necessitating the development of a more effective and safer method for recanalization and embolus management.

Innovation Solution

A catheter-based revascularization system using a self-expanding, reconstrainable nitinol device that compacts emboli against the luminal wall, creating a channel for blood flow and acting as a radial filter to prevent downstream migration, combined with the option of administering lytic agents through the guidewire lumen, allowing for immediate revascularization and reduced risk of complications.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If high-pressure balloon angioplasty is used for recanalization, then immediate lumen patency is achieved, but risk of vessel perforation and hemorrhage increases

Engineering Contradiction:

Improvelumen patencyVSAvoidvessel perforation and hemorrhage

Core Design Contradiction:

ReliabilityVSObject-affected harmful factors

Solution Approach 1:

The patent replaces high-pressure balloon angioplasty with a self-expanding nitinol device that uses elastic memory effect rather than high pressure to achieve vessel opening. The device is delivered in a compressed state and then allowed to self-expand to its original larger diameter, creating lumen patency without the high pressures that cause vessel perforation and hemorrhage

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

Solution Approach 2:

The patent changes the physical parameters of the delivery system by using a self-expanding mechanism instead of pressure-based expansion. The nitinol device transitions from a compressed delivery state to an expanded functional state through its inherent elastic properties, avoiding the high-pressure parameter that causes harmful effects

Inventive Principle:

Principle #35Parameter changes

2Productivity

If clot retrievers are used for embolus removal, then recanalization is attempted, but success rates are limited and multiple passes are required

Engineering Contradiction:

Improverecanalization success rateVSAvoidmultiple passes required

Core Design Contradiction:

ProductivityVSLoss of time

Solution Approach 1:

The patent applies preliminary action by pre-shaping the nitinol device with a distal configuration that automatically engages and compacts the embolus upon deployment. The device is designed beforehand to self-compact the embolus against the vessel wall, creating immediate lumen patency in a single procedure rather than requiring multiple retrieval passes

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The patent implements self-service through the self-expanding nitinol device that automatically compacts the embolus and creates lumen patency without requiring operator manipulation or multiple passes. The device's elastic memory effect causes it to self-expand and self-position to achieve therapeutic effect in a single deployment

Inventive Principle:

Principle #25Self-service

3Ease of operation

If distal wire perforation occurs during procedure, then access to occlusion site is compromised, but procedure must continue

Engineering Contradiction:

Improveaccess to occlusion siteVSAvoidprocedure continuity

Core Design Contradiction:

Ease of operationVSReliability

Solution Approach 1:

The patent uses a flexible catheter system with a soft distal tip that can navigate tortuous vasculature without causing wire perforation. The flexible construction allows the device to conform to vessel walls and follow the natural anatomy, maintaining access to the occlusion site while preventing perforation-related procedure interruptions

Inventive Principle:

Principle #30Flexible shells and thin films

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 achieves immediate 50% lumen patency and natural lysis of emboli, reducing the risk of reocclusions and hemorrhage, while maintaining access to the occlusion site, thereby improving recanalization rates and patient outcomes.

Implementation Method 1

self-expanding, reconstrainable nitinol device that compacts emboli against the luminal wall, creating a channel for blood flow

Methodology Applied

Scientific EffectElastic memory effect: Elasticity

Data Source

PatentUS9198687B2Acute stroke revascularization/recanalization systems processes and products thereby

Publication Date: 2015.12.01 COVIDIEN LP

AI summary

An acute stroke recanalization system and processes include catheter-based improved reconstrainable or tethered neurological devices which are deliverable through highly constricted and tortuous vessels, crossing the zone associated with subject thrombi/emboli, where deployment impacts, addresses or bridges the embolus, compacting the same into luminal walls which enables perfusion and lysis of the embolus, while the improved neurological medical device itself remains contiguous with the delivery system acting as a filter, basket or stand alone stenting mechanism, depending on the status of the embolus and other therapeutic aspects of the treatment being offered for consideration.