Application of Dose Reduction Techniques in CT of Coronary Artery with 64-row Multi-Slice Helical CT

Objective To evaluate the application of dose reduction techniques in CT of coronary artery with 64-row multi-slice CT scanner. Methods 100 consecutive patients who underwent cardiac CT scans were divided into conventional group (C group) and low dose group (L group) with 50 patients in each group. Standard scan technique was used in C group and dose reduction techniques were employed in L group. Image quality, noise, volume CT dose index (CTDIvol), and effective dose (ED) in the two groups were evaluated. Results The mean image quality score was (3.56±0.54) and (3.62±0.57), respectively and the mean image noise in C group and L group was 27.54±4.52 and 27.30±6.15, respectively. There was no significant difference in the image quality score and the mean image noise between the two groups (P0.05). However, the average CTDIvol in C group and L group was (87.91±8.38) mGy and (43.11±4.38) mGy, respectively and the mean ED was (17.96±1.71) mSv and (8.75±0.83) mSv, respectively. The CTDIvol and ED in L group were lower than those in C group(P 0.05). Conclusions Dose reduction techniques in CT of coronary could not only reduce radiation dose to the patient, but also meet the demand of the diagnosis.