Multi-Channel Pilot Tone Motion Detection for Tomographic Imaging

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Subject motion during tomographic medical imaging leads to artifacts in medical images, which existing motion detection techniques struggle to accurately correct.

Innovation Solution

A multi-channel pilot tone system using multiple transmit and receive channels to transmit and receive electromagnetic signals in the radio frequency range, enabling detection of subject motion through impedance response analysis, and utilizing machine-executable instructions and neural networks for motion state determination.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If conventional single-channel pilot tone systems are used, then the system complexity is low, but the motion detection precision and information quality are insufficient

Engineering Contradiction:
Improvemotion detection precisionVSAvoidsystem complexity
Core Design Contradiction:
Measurement precisionVSDevice complexity

Solution Approach 1:

The system divides the single pilot tone channel into multiple independent transmit and receive channels. Each channel transmits or receives pilot tone signals at different frequencies, enabling spatially resolved motion detection. The segmentation of channels provides redundant information paths that improve motion detection precision while maintaining manageable system complexity through modular architecture

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The invention transitions from a single-channel scalar measurement to a multi-channel vector measurement system. By adding the channel dimension, the system captures motion information from multiple spatial perspectives simultaneously, transforming the detection problem from one-dimensional to multi-dimensional, thereby significantly improving motion detection precision

Inventive Principle:
Principle #17Another dimension (Dimensionality change)

2Loss of information

If multiple transmit and receive channels are used, then the information quality and motion detection capability are improved, but the device complexity increases

Engineering Contradiction:
Improveinformation qualityVSAvoiddevice complexity
Core Design Contradiction:
Loss of informationVSDevice complexity

Solution Approach 1:

The multi-channel pilot tone system serves multiple functions simultaneously: it detects periodic motion (breathing), gross motion (body movement), and provides spatially resolved impedance information. Each channel is designed to be multi-functional, handling both transmission and reception duties while contributing to overall system information quality without requiring separate dedicated components for each function

Inventive Principle:
Principle #6Universality (Multi-functionality)

Solution Approach 2:

The system merges multiple pilot tone signals at different frequencies into a unified detection framework. The transmit channels and receive channels are combined into an integrated multi-channel architecture that processes information collectively, reducing the need for separate independent systems and managing device complexity through consolidation

Inventive Principle:
Principle #5Merging (Combining)

3Reliability

If pilot tone signals are transmitted continuously, then the motion detection coverage is improved, but the energy consumption increases

Engineering Contradiction:
Improvemotion detection coverageVSAvoidenergy consumption
Core Design Contradiction:
ReliabilityVSUse of energy by moving object

Solution Approach 1:

Instead of continuous transmission, the system employs periodic pilot tone signal transmission with controlled duty cycles. The transmit channels alternate between active transmission and idle states, maintaining adequate motion detection coverage through periodic sampling while significantly reducing average energy consumption compared to continuous operation

Inventive Principle:
Principle #19Periodic action

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

Provides precise detection of periodic and gross subject motion, allowing for improved monitoring and correction of medical images by simultaneously acquiring and correcting for motion artifacts.

Implementation Method 1

a transmit coil is used to transmit a radio frequency signal and another receive coil is used to receive this signal. The amount of coupling between the subject and these two coils determines the strength of the received signal.

Methodology Applied
Scientific EffectElectromagnetic signal transmission and impedance detection: Electromagnetic Induction

Data Source

PatentEP3973308B1Multi-channel pilot tone motion detection
Publication Date: 2025.11.05 KONINKLIJKE PHILIPS NV
  • EP3973308B1 patent drawingFigure 1
  • EP3973308B1 patent drawingFigure 2
  • EP3973308B1 patent drawingFigure 3

AI summary

Disclosed is a medical system (100, 300, 500, 700) comprising: a memory (128) storing machine executable instructions (130); a processor (122) configured for controlling the medical system; and a pilot tone system (106). The pilot tone system comprises a radio frequency system (108) comprising multiple transmit channels (110) and multiple receive channels (112). The multiple transmit channels are configured for each transmitting unique pilot tone (132) signals via multiple transmit coils. The multiple receive channels are configured for receiving multi-channel pilot tone data (134) via multiple receive coils. Execution of the machine executable instructions causes the processor to: transmit (200) multi-channel pilot tone signals by controlling at least a portion of the multiple transmit channels to transmit the unique pilot tone signals; acquire (202) multi-channel pilot tone data (134) by controlling at least a portion of the multiple receive channels to receive the multi- channel pilot tone data; and determine (204) a motion state (136) of the subject using the multi-channel pilot tone data.