Time-Resolved Light Scattering for Lesion Depth Assessment
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current methods for assessing lesion formation during RF ablation of cardiac tissue lack real-time accuracy, particularly in determining the depth of lesions deeper than 5-8 mm, due to the exponential reduction in detected light signal and noise contamination, limiting the ability to characterize deeper lesions effectively.
Innovation Solution
The use of pulsed illumination sources with ultrashort pulses and broad spectral coverage, combined with time-resolved detection, allows for the analysis of temporal profiles of light propagation through tissue to quantify lesion depth and other formation parameters, enhancing detection limits and accuracy.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Loss of time
If continuous wave NIR spectroscopy is used for lesion depth assessment, then the measurement can be performed in real-time during ablation, but the detection precision for lesions deeper than 5-8 mm deteriorates due to exponential signal reduction
Solution Approach 1:
The patent employs pulsed illumination instead of continuous wave illumination, sending periodic light pulses into the tissue and measuring the temporal profile of scattered light. This time-resolved approach allows separation of signals from different depths based on their arrival times, maintaining measurement precision for deep lesions while enabling real-time assessment during ablation procedures.
Solution Approach 2:
The invention adds the time dimension to the measurement by analyzing the temporal profile of scattered light. Instead of only measuring light intensity at a single wavelength, the system measures how light intensity varies over time after pulsed illumination, creating a time-resolved spectral profile that provides depth information and improves detection precision for deep lesions.
2Device complexity
If conventional spectroscopy measures only spectral information, then the system remains relatively simple, but the ability to distinguish tissue types and assess lesion depth is insufficient
Solution Approach 1:
The patent enhances the measurement by adding the time dimension to conventional spectral measurement. The system captures time-resolved spectral profiles, measuring light intensity as a function of both wavelength and time. This additional temporal information enables better tissue characterization and lesion depth assessment without significantly increasing system complexity, as it builds upon existing spectroscopy infrastructure.
Solution Approach 2:
The invention changes the measurement parameters by incorporating temporal resolution into the spectral measurement. Instead of only measuring spectral composition, the system measures the temporal evolution of scattered light intensity across different wavelengths, providing richer information about tissue optical properties and lesion characteristics while maintaining system simplicity.
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 approach enables more precise real-time assessment of lesion depth and other parameters, such as microbubble formation, with improved signal detection and reduced noise, facilitating safer and more effective RF ablation procedures.
Implementation Method 1
The present invention relates to optical interrogation configurations for investigating tissue modification in real-time during medical procedures... analyzing the spectral characteristics of the diffusely reflected light from the tip of the ablation catheter... by using a pulsed illumination source that produces ultrashort pulses of light with sufficiently broad spectrum or pulses of light that cover specific spectral domains
Data Source
AI summary
A method is described to enhance the ability to evaluate the depth of a tissue component or a lesion having optical properties different from a surrounding tissue using time resolved optical methods. This invention may be particularly suitable for the evaluation of lesion depth during RF ablation (irreversible tissue modification/damage) using specially designed devises (catheters) that deliver heat in a localized region for therapeutic reasons. The technique allows for increased ability to evaluate the depth of the ablated lesion or detect the presence of other processes such as micro-bubble formation and coagulation with higher sensitivity compared to that offered by steady state spectroscopy. The method can be used for in-vivo, real-time monitoring during tissue ablation or other procedures where information on the depth of a lesion or tissue is needed. Exemplary uses are found in tissue ablation, tissue thermal damage, lesion and tissue depth assessment in medical applications.