Clinical Exploration of Low Dose Scanning on 64 Multi-slice Spiral CT Coronary Angiography

Objective To explore the clinical application of low dose scanning on fixed noise level in 64-slice spiral CT coronary angiography (CTCA). Methods Sixty patients with consecutive CTCA scan were divided into two groups. 30 cases as fixed-mA group were retrospectively analyzed, and 30 cases as individual-mA group were prospectively studied on CTCA scan. The image quality, noise, CT dose index volume (CTDIvol) and effective dose (ED) in the two groups were evaluated. Results The two groups had no significant difference in the image quality score and the mean image noise (P 0.05). However, the average CTDIvol and ED in the individual mA group were (99.29 ± 9.04) mGy, (28.10 ± 2.73) mSv respectively, and lower than those in the fixed-mA group by 10.64%, 15.03% respectively (P 0.01). Conclusion Radiation dose can efficiently reduce in the way of the individual adapted tube current selection on fixed noise level to the patients on 64-slice spiral CTCA.