Effects of combining multiple dose reduction techniques on coronary computed tomography angiography.

Abstract

Coronary computed tomography angiography (CCTA) is the preferred non-invasive examination method for coronary heart disease. However, the radiation from computed tomography has become a concern since public awareness of radiation hazards continue to increase. To explore the value of multiple dose reduction techniques for CCTA. Consecutive normal and overweight patients were prospectively divided into two groups: Group A1, patients who received multiple dose reduction scans (n = 82); and group A2, patients who received conventional scans (n = 39). The scan parameters for group A1 were as follows: Isocentric scan, tube voltage = 80 kV, and tube current control using 80% smart milliampere. The scan parameters for group A2 were as follows: Normal position, tube voltage = 100 kV, and smart milliampere. The average effective doses (EDs) for groups A1 and A2 were 1.13 ± 0.35 and 3.36 ± 1.30 mSv, respectively. There was a statistically significant difference in ED between the two groups (P < 0.01). Furthermore, noise was significantly lower, and both signal-to-noise ratio and contrast signal-to-noise ratio were higher in group A2 when compared to group A1 (P < 0.01). Moreover, the subjective image quality (IQ) scores were excellent in both groups, in which there was no significant difference in subjective IQ score between the two groups (P = 0.12). Multiple dose reduction scan techniques can significantly decrease the ED of patients receiving CCTA examinations for clinical diagnosis.