Fully automated tool to identify the aorta and compute flow using phase-contrast MRI: validation and application in a...

Area of Science:

• Cardiovascular Imaging
• Medical Image Analysis
• Radiology

Background:

• Phase contrast (PC) MRI is crucial for assessing cardiovascular function.
• Accurate aortic localization is essential for reliable flow quantification.
• Manual segmentation of the aorta in PC-MRI can be time-consuming and subjective.

Purpose of the Study:

• To develop and validate a fully automated method for localizing the ascending aorta (AAo) and descending aorta (DAo) in PC-MRI.
• To assess the accuracy of automated flow volume measurements for both AAo and DAo.
• To evaluate the robustness of the automated technique in diverse imaging scenarios.

Main Methods:

• A fully automated localization algorithm using the Hough transform was developed for PC cardiac-gated MR images.
• The technique was applied to a large population-based study dataset.
• Validation involved assessing localization performance, accuracy of flow volume generation, and robustness against abnormalities and artifacts.

Main Results:

• The automated algorithm was successfully applied to 1884 participants.
• Excellent correlation (r = 0.99) was observed between automated and manual methods for both AAo and DAo flow volumes.
• Bland-Altman analysis showed strong agreement with minimal bias for AAo and DAo flow measurements.

Conclusions:

• A robust, fully automated tool for aortic localization and flow volume measurement using PC-MRI has been validated.
• This automated technique demonstrates high accuracy and reliability in a large population.
• The method offers a significant advancement for quantitative cardiovascular MRI analysis.