Distal Ablation Current Sensor Using Magnetic Induction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing ablation procedures face challenges in accurately monitoring the amplitude of the ablating current at the distal end of the catheter, as some current is lost to parasitic capacitance, leading to potential under-delivery of energy to the tissue.
Innovation Solution
A sensor is placed at or near the distal end of the catheter, comprising a magnetic core, a coil, and circuitry to measure the amplitude of the ablating current by detecting the induced voltage from the magnetic field produced by the current, allowing for precise estimation and control of the ablating current.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Difficulty of detecting and measuring
If current measurement is performed at the proximal end of the catheter, then measurement simplicity is improved, but measurement precision deteriorates due to current loss to parasitic capacitance
Solution Approach 1:
A magnetic sensor acts as an intermediary measurement device that indirectly measures the ablating current amplitude by detecting the magnetic field generated by the current in the conducting element, rather than directly measuring the electrical current itself. This allows accurate measurement at the distal end without direct electrical contact that would interfere with the ablation current path.
Solution Approach 2:
The patent replaces direct electrical current measurement (electrical system) with magnetic field detection (magnetic system). By measuring the magnetic field amplitude generated by the ablating current through the conducting element, the system indirectly obtains accurate current amplitude information without the losses and interference associated with direct electrical measurement.
2Volume of moving object
If sensor size is reduced to fit within the catheter, then device miniaturization is improved, but manufacturing precision requirements increase
Solution Approach 1:
The magnetic sensor is nested within the catheter body, with the magnetic core positioned around the conducting element and the coil wound around the magnetic core. This nested arrangement allows the sensor components to be compactly integrated within the limited space of the catheter while maintaining their functional relationships.
Solution Approach 2:
The sensor is divided into distinct functional segments: a magnetic core segment, a coil segment, and circuitry segment. This segmentation allows each component to be manufactured separately with standard tolerances and then assembled within the catheter, reducing the cumulative precision requirements compared to manufacturing a single integrated component.
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
This solution ensures that the actual amplitude of the ablating current delivered to the tissue is accurately measured and controlled, enhancing the safety and effectiveness of the ablation procedure by minimizing energy loss and optimizing tissue treatment.
Implementation Method 1
A sensor is placed at or near the distal end of the catheter, comprising a magnetic core, a coil, and circuitry to measure the amplitude of the ablating current by detecting the induced voltage from the magnetic field produced by the current
Data Source
Figure 1
Figure 2A
Figure 2B
AI summary
Ablation apparatus is provided. The apparatus includes an insertion tube, an ablation electrode disposed at a distal end of the tube, a conducting element, and a sensor. The conducting element conducts an ablating current from a proximal end of the tube to the ablation electrode, and the sensor measures an amplitude of the ablating current at the distal end of the tube. Other embodiments are also described.