Low heart rate coronary CT angiography with 320-row detector: A comparison of volume scan and helical scan
10.3724/SP.J.1008.2014.00796
- Author:
Bing XU
1
Author Information
1. Department of Radiology, Changhai Hospital, Second Military Medical University
- Publication Type:Journal Article
- Keywords:
Cone-beam computed tomography;
Coronary angiography;
Low heart rate;
Radiation dosage;
Spiral computed tomography
- From:
Academic Journal of Second Military Medical University
2014;35(7):796-799
- CountryChina
- Language:Chinese
-
Abstract:
Objective: To compare the values of volume scan and helical scan in low heart rate coronary CT angiography. Methods: Coronary CT angiography was done with 320-row detector in 128 patients. The patients were assigned to two groups: Group 1 (n=72) undergoing volume scan and Group 2 (n=56) undergoing helical scan. The heart rates of patients were lower than 65/min during examination. The image quality, radiation dose, and amount of contrast were compared between two groups. Results: The ascending aorta root CT values of group 1 and group 2 were (492.08±58.51) HU and (522.72±56.91) HU, and the image noise of the two groups were (19.64±3.51)HU and (22.66±5.33)HU, respectively. The excellent rates of coronary artery image quality in group 1 and group 2 were 97.5% (632/648) and 96.8% (488/504), and the pass rates were 99.7% (646/648) and 99.2% (500/504), respectively. There were no significant differences concerning image noise, excellent rates of image, or pass rates of image between the two groups (P>0.05). The effective radiation doses were significantly lower in group 1 compared with group 2 ([3.21±0.23] mSv vs [13.27±2.39] mSv, P<0.001). The amounts of contrast in group 1 and group 2 were 50-60 mL and 80-90 mL, respectively. Conclusion: Image quality of coronary CT angiography obtained with volume scan and helical scan can both meet the requirement for clinical diagnosis, but compared with the helical scan, volume scan shows an advantage as it needs lower radiation dose and less contrast.
