Comparison of varying injection rates of saline chasers on intravascular contrast enhancement for dynamic CT in cattle

Dynamic CT was performed in five normal Holstein calves to investigate the effect of saline chasers on intravascular contrast enhancement when administered at three different rates. The five calves were imaged using dynamic CT in a crossover study design. Group A was administered only contrast medium (600 mg iodine/kg, 4 ml/s), while groups B, C and D were administered contrast medium at 30 per cent reduction followed by saline chasers injected at 2, 4 and 8 ml/s, respectively. Attenuation values were obtained from the right and left maxillary arteries and dorsal sagittal sinus. Maximum enhancement value and mean value of the enhancement plateau obtained from the maxillary arteries were significantly lower in group B than in the other groups. The duration of the enhancement plateau was longer in group C than in groups B and D (P<0.05).