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Updated: Jun 26, 2026
11:16
In vitro Assessment of Aortic Regurgitation Using Four-Dimensional Flow Magnetic Resonance Imaging
Published on: February 25, 2022
In vivo velocity and flow errors quantification by phase-contrast magnetic resonance imaging
1Laval Hospital Research Center, Laval University, Quebec, Canada. Julio.Garcia@crhl.ulaval.ca
Summary
Optimizing magnetic resonance imaging (MRI) phase-contrast methods with 16-24 phases minimizes cardiovascular flow errors. A new model corrects time shifts from velocity encoding upsampling, improving accuracy in normal and pathological conditions.
Area of Science:
- Cardiovascular imaging
- Medical physics
- Biomedical engineering
Background:
- Magnetic resonance imaging (MRI) is crucial for cardiovascular assessment.
- Existing MRI techniques face limitations causing measurement errors in velocity and flow.
- Accurate quantification of blood flow is vital for diagnosing and managing cardiovascular diseases.
Purpose of the Study:
- To determine the optimal number of phases for minimizing errors in MRI-derived cardiovascular flow and velocity measurements.
- To investigate the impact of velocity encoding upsampling on flow accuracy.
- To propose methods for reducing measurement errors in clinical settings.
Main Methods:
- In vivo velocity and flow measurements using phase-contrast MRI.
- Systematic evaluation of different numbers of phases (temporal resolution).
- Analysis of the effect of velocity encoding upsampling on flow quantification and introduction of a corrective model.
Main Results:
- An optimal range of 16-24 phases was identified for accurate estimation of ejection and regurgitant flows.
- Velocity encoding upsampling was found to introduce a time shift artifact.
- A corrective linear model was developed to address the time shift artifact.
Conclusions:
- Utilizing 16-24 phases in phase-contrast MRI offers a balance between accuracy and efficiency for cardiovascular flow assessment.
- The proposed corrective model can mitigate errors caused by velocity encoding upsampling.
- These findings enhance the reliability of MRI for evaluating cardiovascular function in both healthy and diseased states.
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