Patient-Tailored Contrast Medium Volume for Preoperative Computed Tomography Angiography of the Aorta Based on Patient's Heart Rate and Body Surface Area.

Objectives: To evaluate the impact of patient-specific contrast volume adjustments on preoperative aortic computed tomography angiography (CTA) image quality after adjusting and reducing the total, injected contrast volume based on patients' body surface area (BSA) and heart rate (HR) and after adapting the CT-scanner's kilovoltage (kV). Methods: Prospective study included 80 surgery-naive patients. Three study groups were included: Group 1 (n = 56 patients): the injected contrast dose, calculated from BSA and HR, was reduced by 50%; Group 2 (n = 11 patients): the injected contrast dose, calculated from BSA and HR, was reduced by 50%, and an additional volume reduction was based on the kV values; Group 3 (n = 13 patients): the injected contrast dose, calculated from BSA and HR, was reduced by 50% and additionally diluted to 80% contrast and 20% saline. Image quality was evaluated by quantitative analysis (Hounsfield units) and qualitative analysis (five-point visual score). Results: The mean injected contrast dose was 46.1 ml, 28.3 ml, and 35.0 ml in Groups 1, 2, and 3, respectively, with a significant difference between Group 1 vs Group 2 (P < 0.001) and between Group 1 vs Group 3 (P < 0.001). A linear relationship between the Hounsfield units and the given contrast dose for all study groups was observed. The mean image quality score for Group 1 was 4.34/5. The mean image quality score for Group 2 was 2.8/5 and for Group 3 was 3.5/5. Conclusions: Significant contrast dose reduction, based on HR and BSA, in preoperative aortic CTA is associated with acceptable diagnostic quality.