Double Balloon Catheter Fail-Safe Containment Design
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing balloon catheters for cryotreatment lack robustness in containing cryogenic coolants, as they often employ mechanically rigid structures that can lead to leaks or ruptures if the containment mechanisms fail, posing a risk of coolant leakage into the body.
Innovation Solution
A double balloon catheter design with a first expandable membrane defining a cooling chamber and a second expandable membrane around it, where the second membrane has a higher pressurization limit, along with a control unit and sensors to monitor and control fluid flow, temperatures, and pressures, ensuring a 'fail-safe' operation by containing any leaks and preventing coolant from entering the body.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If thicker balloons and mechanically rigid cooling chambers are employed to contain coolant, then containment strength is improved, but device complexity and risk of catastrophic failure increase
Solution Approach 1:
The containment system is divided into multiple independent balloon layers (inner balloon, outer balloon, and optionally intermediate balloons) with different pressurization limits. Each balloon acts as an independent containment barrier, so that if one fails, the others remain intact to prevent coolant leakage into the body.
Solution Approach 2:
The system incorporates redundant containment balloons designed to activate or maintain integrity after inner balloon failure. The outer balloon with higher pressurization limit serves as a pre-positioned safety barrier that prevents catastrophic coolant release if the inner balloon ruptures, providing beforehand protection against failure.
2Reliability
If thicker balloons are used to contain coolant, then reliability is improved, but ease of operation and flexibility decrease
Solution Approach 1:
The containment function is segmented across multiple thin balloon layers rather than relying on a single thick balloon. This allows each layer to remain flexible and easy to navigate through blood vessels while collectively providing robust containment through redundancy.
Solution Approach 2:
The patent employs multiple flexible balloon membranes instead of rigid thick-walled structures. These thin-film balloons maintain flexibility for navigation through the vasculature while providing reliable containment through their layered redundant configuration.
3Stability of the object's composition
If mechanically rigid cooling chambers are used, then structural integrity is improved, but adaptability and safety against rupture decrease
Solution Approach 1:
The system uses dynamic, flexible balloon structures that can expand and contract as needed rather than fixed rigid chambers. The balloons can adapt their shape and volume while maintaining containment integrity, and the redundant layered design ensures that structural failure of one element does not compromise the entire system.
Solution Approach 2:
The containment system combines multiple balloon materials with different mechanical properties and pressurization limits into a composite structure. This layered composite approach provides both flexibility and enhanced safety, as each material layer contributes different strengths and failure characteristics.
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 double balloon catheter design significantly enhances safety by minimizing the risk of coolant leakage, providing a robust containment mechanism that maintains structural integrity even if the inner balloon fails, thus ensuring safe and effective cryotreatment procedures.
Implementation Method 1
Upon injection from the orifice, the refrigerant undergoes two primary thermodynamic changes: (i) expanding to low pressure and temperature through positive Joule-Thomson throttling
Implementation Method 2
undergoing a phase change from liquid to vapor, thereby absorbing heat of vaporization
Implementation Method 3
cooling a portion of the device to very low temperature through conductive and convective heat transfer between the cryogen and target tissue
Implementation Method 4
cooling a portion of the device to very low temperature through conductive and convective heat transfer between the cryogen and target tissue
Data Source
Figure 1
Figure 2~3
AI summary
A catheter (34) includes a first expandable membrane (62) having a first pressurization limit and a second expandable membrane (64), having a second pressurization limit, wherein the second pressurization limit is greater than the first pressurization limit, the first expandable membrane defines a cooling chamber, the second expandable membrane being disposed around the first expandable membrane to define an junction (57) therebetween. The catheter includes a coolant injection lumen in fluid communication with the at least one fluid inlet port and the cooling chamber, and a primary coolant return lumen in fluid communication with the at least one fluid outlet port and the cooling chamber. The coolant injection tube, the cooling chamber, and the primary coolant return lumen define a first fluid pathway. The catheter further includes a secondary coolant return lumen in fluid communication with the at least one fluid outlet port and the junction. The junction and the secondary coolant return lumen define a second fluid pathway. The catheter provides a fail-safe feature by selecting the appropriate first and second pressurization limits for the first and second expandable membranes.