Cardiac CT Acquisition Time Adjustment for Heart Rate Variability

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Current cardiac CT imaging systems face challenges in minimizing radiation dose while ensuring optimal image quality, particularly due to heart rate variability, which often requires extending the acquisition time period with a safety margin (padding time) that may be inappropriate and increase the radiation dose unnecessarily.

Innovation Solution

The method involves determining heart rate variability by statistically analyzing R-peak times from ECG data and automatically adjusting the acquisition time period of the cardiac CT imaging system, allowing for real-time compensation of short-term changes in heart rate, thereby minimizing the acquisition time and reducing the radiation dose.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If the acquisition time period is extended with a safety margin (padding time) to account for heart rate variability, then the reliability of data acquisition is improved, but the radiation dose increases

Engineering Contradiction:
Improvereliability of data acquisitionVSAvoidradiation dose
Core Design Contradiction:
ReliabilityVSObject-affected harmful factors

Solution Approach 1:

The acquisition time period is made dynamically adjustable based on the measured heart rate variability. The system automatically adapts the padding time to the actual physiological conditions of the patient, extending it only when necessary rather than using a fixed conservative margin for all patients.

Inventive Principle:
Principle #15Dynamics

Solution Approach 2:

The system changes the acquisition time period parameter based on the statistical analysis of heart rate variability. By calculating the standard deviation of R-peak intervals and using this to determine the appropriate padding time, the system optimizes the acquisition parameters to match actual patient conditions.

Inventive Principle:
Principle #35Parameter changes

2Manufacturing precision

If the acquisition time period is increased to ensure sufficient data acquisition for unstable heart rates, then the manufacturing precision of the image reconstruction is improved, but the loss of time increases

Engineering Contradiction:
Improveimage reconstruction qualityVSAvoidacquisition time
Core Design Contradiction:
Manufacturing precisionVSLoss of time

Solution Approach 1:

The acquisition time period is dynamically adjusted based on real-time heart rate variability assessment. For stable heart rates, the system uses minimal padding time, while for unstable heart rates, it extends the acquisition period only to the extent necessary to ensure adequate data coverage.

Inventive Principle:
Principle #15Dynamics

Solution Approach 2:

The system performs self-adjustment by automatically analyzing the patient's ECG data, determining heart rate variability, and setting the appropriate acquisition time period without requiring manual intervention or fixed conservative margins.

Inventive Principle:
Principle #25Self-service

3Ease of operation

If a fixed padding time is used for all patients, then the ease of operation is improved, but the adaptability to individual heart rate variability decreases

Engineering Contradiction:
Improveoperation simplicityVSAvoidadaptability to heart rate variability
Core Design Contradiction:
Ease of operationVSAdaptability or versatility

Solution Approach 1:

The system automatically performs ECG analysis, calculates heart rate variability, and determines the optimal acquisition time period without requiring manual input or adjustment by the operator. This maintains ease of operation while achieving individualized adaptation.

Inventive Principle:
Principle #25Self-service

Solution Approach 2:

The system uses feedback from the patient's ECG signal to automatically adjust the acquisition parameters. By continuously monitoring heart rate variability and using this information to set the padding time, the system adapts to individual patient conditions while requiring minimal operator involvement.

Inventive Principle:
Principle #23Feedback

Data Source

PatentEP3509495B1Cardiac computed tomography
Publication Date: 2022.11.09 KONINKLIJKE PHILIPS NV
  • EP3509495B1 patent drawingFigure 1A~1B
  • EP3509495B1 patent drawingFigure 2~3
  • EP3509495B1 patent drawing

AI summary

A method for operating a cardiac CT imaging system (200) in coronary CT with prospective electrocardiography-triggering of the imaging system (200) is proposed. The method comprises the steps of determining a plurality of R-peak times (ti) from a dataset of electrocardiography data, determining a variability of a heart rate by statistically analyzing the determined R-peak times (ti), and automatically adjusting an acquisition time period (ΔTac) of the CT imaging system (200) for acquiring projection data based on the determined variability of the heart rate.