Robust segmentation methods with an application to aortic pulse wave velocity calculation

Area of Science:

• Cardiovascular imaging and analysis
• Medical image processing
• Biomedical engineering

Background:

• Aortic stiffness is a key indicator of cardiovascular disease and overall cardiovascular health.
• Pulse wave velocity (PWV) and aortic distensibility are vital measures of aortic stiffness and elasticity.
• Accurate measurement of PWV and distensibility from MRI requires robust segmentation and signal processing.

Purpose of the Study:

• To present a novel, robust image processing toolbox for calculating aortic stiffness (PWV and distensibility) from MRI data.
• To develop advanced segmentation techniques for accurate thoraco-abdominal aorta centerline extraction and transverse aortic region delineation.
• To introduce a new method for analyzing velocity curves to determine pulse wave propagation times.

Main Methods:

• A novel graph-based method for 3D thoraco-abdominal aorta centerline extraction from non-contrasted abdominal MRI.
• A new projection-based segmentation method for transverse aortic region delineation in cardiac MRI, robust to artifacts.
• A novel method for velocity curve analysis to obtain pulse wave propagation times.
• Validation against manual segmentations and a validated software for PWV measurement.

Main Results:

• The developed toolbox provides a complete solution for aortic PWV and distensibility calculation.
• The graph-based centerline extraction is robust to artifacts and noise.
• The projection-based segmentation effectively delineates aortic regions even with high artifact presence.
• Validation demonstrated high correctness and effectiveness of the proposed methods.

Conclusions:

• The novel image processing toolbox offers a correct and effective approach for calculating aortic PWV and distensibility from MRI.
• The developed segmentation techniques are robust and suitable for clinical application in cardiovascular assessment.
• This work advances non-invasive methods for evaluating aortic stiffness and cardiovascular health.