MRI Thermometry Uncertainty Maps for Dynamic Boundary Adjustment

Solution Overview

Problem

MRI-guided thermal therapies face errors due to transient motion and temperature measurement uncertainties, leading to unintended heating or lack of heating in target regions, resulting in suboptimal treatment sessions and reduced efficiency.

Innovation Solution

A method that dynamically calculates and displays temperature uncertainty maps using MRI data to determine reliable treatment regions, allowing clinicians to adjust the anatomical boundary and thermal therapy applicator position based on these maps, thereby minimizing uncertainty and ensuring accurate thermal therapy delivery.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If temperature measurements are used as part of a feedback system for thermal energy delivery, then treatment accuracy is improved, but measurement errors from transient motion cause unintended heating or lack of heating

Engineering Contradiction:

Improvetemperature measurement accuracyVSAvoidtreatment reliability

Core Design Contradiction:

Measurement precisionVSReliability

Solution Approach 1:

The system performs preliminary motion detection and pause decisions before completing the thermal therapy treatment. Motion detection is continuously monitored during treatment, and when motion exceeding a threshold is detected, the system proactively pauses the thermal energy delivery to prevent measurement errors and unintended heating, rather than waiting for errors to manifest

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The system implements a feedback loop where temperature measurements and motion detection continuously inform treatment decisions. The feedback mechanism compares actual temperature readings against expected values, detects motion artifacts, and automatically adjusts or pauses thermal energy delivery to maintain treatment accuracy and reliability

Inventive Principle:

Principle #23Feedback

2Measurement precision

If the treatment session is paused to wait for temperature to stabilize, then measurement accuracy is improved, but patient throughput and facility efficiency are reduced

Engineering Contradiction:

Improvetemperature measurement accuracyVSAvoidpatient throughput

Core Design Contradiction:

Measurement precisionVSProductivity

Solution Approach 1:

The system performs preliminary motion detection and pause decisions before completing the thermal therapy treatment. Motion detection is continuously monitored during treatment, and when motion exceeding a threshold is detected, the system proactively pauses the thermal energy delivery to prevent measurement errors and unintended heating, rather than waiting for errors to manifest

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The system dynamically adjusts treatment timing based on real-time motion detection. Rather than using fixed pause durations, the system adapts the pause length and frequency to the actual motion conditions observed during each treatment session, optimizing both measurement accuracy and treatment efficiency for each patient

Inventive Principle:

Principle #15Dynamics

3Measurement precision

If the anatomical boundary is modified dynamically during treatment, then treatment accuracy is improved, but the complexity of the treatment system increases

Engineering Contradiction:

Improveanatomical boundary accuracyVSAvoidtreatment system complexity

Core Design Contradiction:

Measurement precisionVSDevice complexity

Solution Approach 1:

The system performs preliminary motion detection and pause decisions before completing the thermal therapy treatment. Motion detection is continuously monitored during treatment, and when motion exceeding a threshold is detected, the system proactively pauses the thermal energy delivery to prevent measurement errors and unintended heating, rather than waiting for errors to manifest

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The system implements a feedback loop where temperature measurements and motion detection continuously inform treatment decisions. The feedback mechanism compares actual temperature readings against expected values, detects motion artifacts, and automatically adjusts or pauses thermal energy delivery to maintain treatment accuracy and reliability

Inventive Principle:

Principle #23Feedback

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 improves the accuracy and efficiency of thermal therapy by reducing errors caused by transient motion, enhancing patient comfort and treatment outcomes while optimizing the use of MRI-thermal therapy facilities.

Implementation Method 1

using a thermal therapy applicator comprising an ultrasound transducer array, delivering a thermal therapy dose to said target volume

Methodology Applied

Scientific EffectAcoustic heating: Ultrasonic Vibration

Implementation Method 2

receiving N sets of temperature data for pixels corresponding to a portion of a patient's body, each set of temperature data corresponding to a respective capture time of phase images captured using a magnetic resonance imaging (MRI) device

Methodology Applied

Scientific EffectMRI thermometry: Magnetic Field

Data Source

PatentUS11471053B2Thermal therapy with dynamic anatomical boundaries using MRI-based temperature uncertainty maps

Publication Date: 2022.10.18 PROFOUND MEDICAL

AI summary

Temperature uncertainty maps are calculated based on a rolling window of temperature maps, which is updated as new temperature maps are generated. The rolling window mitigates the effect of transient motion during a thermal therapy procedure. A clinician or an automated control system can then update a portion of an anatomical boundary or the thermal therapy applicator center based on the temperature uncertainty map.