Individualized contrast agents injection protocol tailored to body surface area in coronary computed tomography angiography.

BACKGROUND: The degree of intravascular enhancement influences the diagnosis of plaque in coronary computed tomography angiography (CTA).

PURPOSE: To evaluate whether the protocol tailored to body surface area (BSA) achieving identical enhancement in different habitus patients receiving different concentration contrast agents (CA) in coronary CTA.

MATERIAL AND METHODS: Patients undergoing coronary CTA randomly received a different concentration of CA with a protocol adapted to BSA. Attenuation and standard deviation were measured at ascending aorta (AAo), left anterior descending coronary artery (LAD), right coronary artery (RCA), paraspinal muscle and peri-coronary adipose tissue. Attenuation and Contrast-to-Noise-Ratio (CNR) were compared among CA groups and BMI-subgroups. Data were compared using ANOVA one-way test, paired Student t test, chi-square test and Kappa test.

RESULTS: In different CA concentration groups, there were no significant differences in attenuation of AAo (477.72, 486.98, 474.50 HU, P = 0.29), LAD proximal (478.47, 487.50, 476.21 HU, P = 0.25) and distal portion (448.81, 451.94, 443.83 HU, P = 0.28), RCA proximal (463.11, 465.60, 479.66 HU, P = 0.09) and distal portion (438.90, 441.36, 448.49 HU, P = 0.27). The enhancement of coronary distal portion were lower than proximal portion (all P < 0.01). No significant differences in CNR of LAD (43.24, 47.37, 44.47, P = 0.12) and RCA (51.74, 50.86, 51.86, P = 0.77) were found among CA groups. There were no significant differences in vascular enhancement among BMI-subgroups (all P > 0.05). Overall subjective image quality and agreement were good.

CONCLUSION: With the CA injection protocol tailored to BSA, it is feasible to obtain consistent contrast enhancement and image quality in coronary CTA, regardless of CA concentration and patient habitus.