Application value of prospective electrocardiogram-gating for 64-slice CT coronary angiography / 中国医学影像技术

ABSTRACT

Objective To compare radiation dose and image quality between prospective and retrospective ECG gating CT coronary angiography (CTCA) with 64-slice CT scanner. Methods Sixty patients with suspected coronary artery disease were selected, and randomly devided into two groups. Thirty patients in research group (average body-mass index [BMI][25.30±3.15] kg/m~2, heart rate ≤65 beats per minute [bpm]) underwent CTCA using prospective ECG-gating (120 kV, mA tailored to weight), while the rest 30 patients in control group (average BMI[25.40±3.00] kg/m~2, heart rate ≤65 bpm) underwent CTCA using retrospective ECG-gating (120 kV, 650 mA). The average effective dose (ED) and standardizing radiation dose (ED_(Sd)) which was standardized by 12 cm length were respectively calculated, and statistical analysis was then conducted, meanwhile image quality was evaluated. Results The average ED of research group and control group was (5.97±1.04) mSv and (26.25±2.36) mSv, respectively (t_(A,B)=43.13, P<0.05). The ED_(Sd) of two groups was (5.49±0.45) mSv and (23.77±1.64) mSv (t_(Sd)=59.00, P<0.05). ED_(Sd) decreased by 76.62% in research group compared with that of control group. No significant difference of image quality was found between two groups (χ~2=4.26, P=0.235). Conclusion Prospective ECG-gating CTCA can effectively reduce radiation dose without compromising image quality.