Contrast medium injection protocols for coronary CT angiography: should contrast medium volumes be tailored to body weight or body surface area?

<bold>Aim: </bold>To compare the uniformity and image quality between contrast media injection protocols adjusted for patient body weight (BW) versus body surface area (BSA) during coronary computed tomography (CT) angiography (CCTA).<bold>Materials and Methods: </bold>Consecutive patients (n=489) with suspected coronary artery disease were randomised prospectively to one of two CCTA protocols. In the BW protocol (n=245), patients received individualised iodine delivery rates (≤50 kg: 1 g/s; 51-60 kg: 1.2 g/s; 61-70 kg: 1.4 g/s; 71-80 kg: 1.6 g/s; 81-90 kg: 1.8 g/s; 91-100 kg: 2 g/s; >100 kg: 2.2 g/s). In the BSA protocol (n=244), patients received 9,600 mg iodine/m2 of contrast medium over 12 seconds. Attenuation and image noise were measured. Signal-to-noise ratio and contrast-to-noise ratio were calculated. Image quality was scored. Attenuation was assessed for correlation with BW and BSA using linear regression.<bold>Results: </bold>There were no statistically significant differences in mean arterial attenuation (396.8±47.6 versus 395.8±42.2 HU, p=0.804; 95% confidence interval: -7 to 9), image noise (25.2±5.8 versus 25.5±5.4 HU; p=0.549), signal-to-noise ratio (16.7±4.4 versus 16.6±3.6; p=0.902), contrast-to-noise ratio (25.1±5.8 versus 25.8±7.4; p=0.258) or image quality scores (4.1±0.9 versus 4±0.9; p=0.770) between the BW and BSA protocols. There was no correlation between BW and aortic attenuation or between BSA and aortic attenuation (p=0.324 and 0.932, respectively).<bold>Conclusion: </bold>The average contrast media attenuation and image quality was comparable between BW-adjusted protocol and BSA-adjusted protocol. [ABSTRACT FROM AUTHOR]