Peak enhancement of the liver in children using power injection and helical CT.

Abstract

Our objective was to determine the level and timing of peak hepatic enhancement in children using power injection of contrast media, helical CT, and computer-automated scan technology. Forty-nine abdominal CT studies were performed using computer-automated scan technology. Patients were divided into four groups on the basis of body weight and contrast dose (group 1A, < or = 20 kg and 2 ml/kg; group 1B, < or = 20 kg and 3 ml/kg; group 2, 21-40 kg and 2 ml/kg; group 3, > 40 kg and < or = 2 ml/kg). Contrast injection rates were based on body weight (groups 1A and 1B, 1 ml/sec; group 2, 1.5 ml/sec; and group 3, 2 ml/sec). The peak hepatic enhancement level in Hounsfield units and the time to reach peak enhancement were determined for each patient. The mean peak hepatic enhancement and time to peak enhancement after completion of contrast injection were group 1A, 45 H and 11 sec; group 1B, 62 H and 3 sec; group 2, 52 H and 12 sec; and group 3, 45 H and 10 sec. The level and timing of peak hepatic enhancement in pediatric patients can be obtained using computer-automated scan technology. These data may then be used to optimize hepatic enhancement when obtaining helical abdominal CT scans of pediatric patients.