Protocolo para inyeccion de medio de contraste en angiografia aortica abdominal con tomografo multicortes

ABSTRACT

60 patients (58 percent males, ages in the range 16 to 81 years and body weights 43 to 100 kg) were injected with a test bolus of 16 mL of contrast material, at a constant speed of 4 mL/sec, for transit time measurement, and a diagnostic volume injection of 109 mL of contrast material, with an exponentially decaying speed (initial value, 4 mL/sec). Imaging was started at 10 seconds plus the specific transit time of each patient. Enhancement was determined in HU in three aortic regions (the celiac axis, distal aorta and common iliac artery). Injected contrast material volume was one and the same (109 + 16 = 125 mL, 350 mg/mL iodine) for every patient. Average enhancement in HU for the three ROIs and its variation coefficient were calculated for each patient. Correlations (linear regressions) were estimated between the different variables average HU, body weight, body mass index, transit times and ages. Contrast homogeneity along the artery was excellent variation coefficient in the range of 1 percent to 13.5 percent. Correlation of average enhancement in HU with body weight in kg was inverse (as expected) but weak R² = 0.226. This justified our a priori decision for a unique injected contrast volume, independently of body weight.