Measurement of coronary bifurcation angle with coronary CT angiography: A phantom study. (January 2018)

• Record Type: Journal Article
• Authors: Givehchi, Sogol; Safari, Mohammad Javad; Tan, Sock Keow; Md Shah, Mohammad Nazri Bin; Sani, Fadhli Bin Mohamed; Azman, Raja Rizal; Sun, Zhonghua; Yeong, Chai Hong; Ng, Kwan Hoong; Wong, Jeannie Hsiu Ding
• Is Part Of: Physica medica. Volume 45(2018)
• Page Start: 198
• Page End: 204
• Publication Date: 2018-01
• Subjects: Atherosclerosis -- Coronary artery disease -- Bifurcation angle -- Coronary CT angiography; Medical physics -- Periodicals; Biophysics -- Periodicals; Biophysics -- Periodicals; Imagerie médicale -- Périodiques; Radiothérapie -- Périodiques; Rayons X -- Sécurité -- Mesures -- Périodiques; Physique -- Périodiques; Médecine -- Périodiques; 610.153
• DOI: 10.1016/j.ejmp.2017.09.137
• Languages: English
• ISSNs: 1120-1797

Abstract

Highlights: The accuracy of MPR and VRT techniques in measuring bifurcation angle is investigated. In phantom setting, these methods demonstrated a significant correlation to the true bifurcation angle. In clinical context, large differences were found between bifurcation angles measured by the two techniques. Abstract: Purpose: Accurate determination of the bifurcation angle and correlation with plaque buildup may lead to the prediction of coronary artery disease (CAD). This work evaluates two techniques to measure bifurcation angles in 3D space using coronary computed tomography angiography (CCTA). Materials and Methods: Nine phantoms were fabricated with different bifurcation angles ranging from 55.3° to 134.5°. General X-ray and CCTA were employed to acquire 2D and 3D images of the bifurcation phantoms, respectively. Multiplanar reformation (MPR) and volume rendering technique (VRT) were used to measure the bifurcation angle between the left anterior descending (LAD) and left circumflex arteries (LCx). The measured angles were compared with the true values to determine the accuracy of each measurement technique. Inter-observer variability was evaluated. The two techniques were further applied on 50 clinical CCTA cases to verify its clinical value. Results: In the phantom setting, the mean absolute differences calculated between the true and measured angles by MPR and VRT were 2.4° ± 2.2° and 3.8° ± 2.9°, respectively. Strong correlation was found between the true and measured bifurcation angles. Furthermore, no significant differences were found between the bifurcation angles measured using either technique. In clinical settings, large difference of 12.0° ± 10.6° was found between the two techniques. Conclusion: In the phantom setting, both techniques demonstrated a significant correlation to the true bifurcation angle. Despite the lack of agreement of the two techniques in the clinical context, our findings in phantoms suggest that MPR should be preferred to VRT for the measurement of coronary bifurcation angle by CCTA.