Automatic determination of differential coronary artery motion minima for cardiac computed tomography optimal phase...

Area of Science:

• Cardiovascular Imaging
• Radiology
• Medical Algorithms

Background:

• Optimal phase selection in cardiac computed tomography (CT) for coronary artery evaluation is challenging, particularly at higher heart rates.
• The ideal imaging phase can vary significantly between individual coronary arteries.
• Existing global motion algorithms may not adequately address vessel-specific motion variations.

Purpose of the Study:

• To evaluate a novel vessel-specific algorithm for automatically identifying the minimum motion phase for each coronary artery.
• To compare the image quality achieved by the vessel-specific algorithm against a standard global motion algorithm.

Main Methods:

• 44 patients undergoing 256-slice cardiac CT for chest pain evaluation were included.
• A novel vessel-specific algorithm was developed to calculate minimum motion phases for each of the three main coronary arteries separately.
• Image quality was blindly assessed by two readers, with median scores compared using the Wilcoxon signed rank test.

Main Results:

• The vessel-specific algorithm yielded significantly higher mean image quality scores (4.0 ± 0.61) compared to the global phase selection (3.80 ± 0.69; P < .001).
• Significant variation in optimal phases was observed between coronary arteries within the same patient (5.0 ± 4.5% for end-systole, 4.8 ± 4.1% for mid-diastole).
• The vessel-specific approach resulted in superior image quality for 46 out of 122 evaluated coronary arteries.

Conclusions:

• Optimal image quality for all three coronary arteries necessitates the use of multiple, distinct phases.
• A vessel-specific phase selection algorithm demonstrates superior performance compared to standard global phase selection methods in cardiac CT.
• This approach enhances diagnostic accuracy by providing clearer visualization of individual coronary arteries.