Impact of tube voltage on image quality and radiation dose in CT coronary angiography: a comparative study of 100 and 120 kVp protocol

Abstract Background CT coronary angiography (CTCA) is a widely used non-invasive method for evaluating coronary artery disease. Tube voltage plays a crucial role in influencing both radiation dose and image quality. The aim of this study was to compare the impact of tube voltage settings of 100 and 120 kVp on image quality and radiation dose in CTCA with a focus on optimizing the protocol for different BMI categories. Results The 100kVp protocol demonstrated a statistically significant reduction in effective dose (10.71 ± 1.74 mSv) compared to 120kVp protocol (17.82 ± 1.40) with a p value of < 0.001, representing a 39% decrease. SNR and CNR were significantly improved at 100kVp despite a moderate increase in the image noise. Qualitative image score showed a high interobserver agreement (Cohen’s kappa > 0.75). Conclusion Reducing the tube voltage to 100kVp in patients with low or normal BMI significantly lowers radiation dose without compromising diagnostic image quality in CTCA. These results support the implementation of BMI-based CTCA protocols for enhanced patient safety.