Coronary angiography by 128 multi-slice dual source CT with multiple scan modes
LEI Wei1, XU Xiu-fang2, YU Ri-sheng3, CUI Feng1, XU Kun-yuan1
1. Department of Radiology, Hangzhou TCM Hospital, Hangzhou 310007, China;2. Zhejiang Medical College, Hangzhou 310053, China;3. Department of Radiology, Second Affiliated Hospital, Medical College of Zhejiang University, Hangzhou 310009, China
Abstract：Objective: To evaluate the application of multiple scan modes in 128-slice dual-source CT coronary angiography. Methods: 603 patients of chest pain and chest tightness with heart rate ≤65bpm were examined by CT coronary angiography. 186 patients were examined using the prospective ECG-gated flash spiral(FS) mode; 102 patients were examined using the prospectively ECG-gated sequence(S) mode; 315 patients were examined using the retrospective ECG-gated low-pith spiral(LS) mode, in which 45 cases had arrhythmia. The radiation dose of three modes was used for analysis of variance. The radiation dose was compared between the group of normal cardiac rhythm and the group of arrhythmia. Results: The percentage of diagnosable segments was similar with 99.4% for FS mode, 99.5% for S mode and 99.2% for LS mode, but there was significant difference among three modes in radiation dose with (0.91±0.05) mSv for FS mode and (5.48±0.95) mSv for S mode and (9.19±3.00) mSv for LS mode(P<0.01). There were 270 patients of normal cardiac rhythm and 45 patients of arrhythmia in LS mode scanning, and there was significant difference in radiation dose with (8.45±2.44) mSv for the group of normal cardiac rhythm and (13.62±2.09) mSv for the group of arrhythmia(t=-13.428, P<0.01). Conclusion: The three modes(FS, S and LS) of 128-slice dual-source CT coronary angiography can obtain good image quality, but the radiation dose of FS mode were further significantly lower compared with S mode and LS mode. FS mode is an effective means to achieve low radiation dose for CT coronary angiography. Different scanning modes should be used according to the heart rate and rhythm of the patients to enable scan optimization.
2012, Vol. 23 
