Comparison of image quality in coronary artery visualization by electron beam CT and multislice spiral CT

Objective: To compare the image quality of coronary artery visualization by electron beam CT (EBCT) and multislice spiral CT (MSCT). Methods: Twenty-three patients with suspected coronary artery disease underwent both EBCT and MSCT. Overall length of the visualized coronary arteries and evaluable vessel length were measured, image quality of coronary arteries was evaluated, and different three-dimensional reconstruction methods were compared by two experienced cardiovascular radiologists. Results: There was no significant difference that overall visualized length of the coronary arteries between MSCT and EBCT, but MSCT depicted significantly longer diagnosable segments of the left anterior descending (length: [77.1 ± 16.8] vs [59.3 ± 22.1] mm, P<0.05) and the left circumflex coronary arteries (length: [65.8 ± 19.5] vs [48.3 ± 17.3] mm, P<0.01) than EBCT. In MSCT, the segments' percentage both quality A and quality B were higher than that in EBCT, as well as the percentage of diagnosable segments (P<0.01). On the contrary, a significantly smaller proportion of quality C segments of the coronary arteries was visualized in MSCT. Of all segments of quality C in MSCT, most were mid right coronary arteries, and in EBCT were distal segments of left anterior descending and circumflex coronary arteries. Noncalcification plaques within upper, lower or lateral vascular wall were more easily shown by MSCT. The imaging quality of reconstructed coronary arteries by conventional three-dimensional reconstruction methods in MSCT were better than that in EBCT except cross section maximum intensity projection. Conclusion: Because its higher spatial resolution and lower image noise, MSCT seems to be superior to EBCT in the visualization of the coronary arteries despite motion artifacts of right coronary artery were more frequent than in EBCT. Both EBCT and MSCT enable non-invasive visualize coronary arteries and evaluate coronary artery diseases.