Six Degrees of Freedom Catheter Navigation via Inductive Pickup Coil
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current catheter navigation systems face challenges in accurately determining the position and orientation of the distal portion of the catheter in six degrees of freedom, particularly due to deformation of body tissues during procedures and the limitations of two-dimensional fluoroscopic imaging, which can lead to misalignment with the target and difficulties in navigating through respiratory and cardiac movements.
Innovation Solution
A catheter navigation system equipped with a flexible catheter featuring a five degrees of freedom sensor and a drive mechanism with pull wires, which allows for real-time detection and adjustment of the catheter's position and orientation, including calculation of the roll component, using a computing device to signal movements and display user interfaces for precise navigation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If a five degrees of freedom sensor is used to detect catheter position and orientation, then the measurement precision of position and orientation is improved, but the roll component cannot be directly measured, requiring additional calculation
Solution Approach 1:
The patent uses the drive mechanism as an intermediary to provide the missing roll angle information. The drive mechanism, which controls the pull wires to articulate the catheter, serves as a mediator between the 5DOF sensor detection and the complete 6DOF pose representation, filling in the roll component that the sensor cannot directly measure.
Solution Approach 2:
The patent replaces direct mechanical measurement of roll angle with a computational approach. Instead of using additional mechanical sensors to directly measure roll, the system uses computational geometry and the known relationships between pull wire positions, catheter shape, and sensor readings to calculate the roll component, substituting mechanical measurement with information processing.
2Measurement precision
If real-time imaging is used to track catheter position, then the accuracy of target alignment is improved, but the system complexity and cost increase
Solution Approach 1:
The patent extracts the essential positioning information from complex real-time imaging systems and represents it through a simplified computational model. Instead of relying on complex imaging processing, the system extracts position and orientation data directly from the drive mechanism and sensor readings, eliminating the need for complex image analysis while maintaining accuracy.
Solution Approach 2:
The patent creates a virtual copy or digital representation of the catheter's position and orientation in 6DOF space. This digital twin approach allows the system to track and visualize catheter position without requiring complex real-time imaging infrastructure, using computational geometry to maintain an accurate virtual model of the catheter's state.
3Ease of operation
If the catheter is made flexible to navigate through luminal networks, then the ease of operation is improved, but the stability of position and orientation detection deteriorates
Solution Approach 1:
The patent segments the catheter into multiple articulation points controlled by individual pull wires. This segmentation allows different portions of the flexible catheter to be independently positioned and oriented, maintaining stability in the distal portion while preserving flexibility in the proximal sections, enabling both navigability and detection accuracy.
Solution Approach 2:
The patent implements dynamic control of the flexible catheter through real-time adjustment of pull wire tension. The system dynamically adjusts the catheter's shape and orientation during navigation, allowing the distal portion to stabilize at desired positions while the proximal portions remain flexible for navigation, balancing stability and ease of operation through active control.
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 enables accurate and precise navigation of the catheter in six degrees of freedom, reducing errors caused by tissue deformation and movement, and ensuring accurate alignment with the target, even in dynamic environments like the lungs.
Implementation Method 1
a 5DOF inductive pickup coil sensor
Data Source
AI summary
A method and system of detecting a position and orientation of the catheter in five degrees of freedom (5DOF) in a first position and in a second position and calculating a sixth degree of freedom of the catheter based on a difference in the detected 5DOF position and orientation of the catheter in the first position and the detected 5DOF position and orientation in the second position.