Pediatric hepatic CT: an injection protocol.
OBJECTIVE
To determine an injection protocol for pediatric hepatic CT and to investigate the use of power injection.


METHODS
Eighty-seven studies were prospectively performed using ioversol (320 mg iodine per cc) at 2 cc/kg. Three techniques were used: helical (1 s/slice); dynamic, non-breath-hold (5.5 s/slice); dynamic, breath-hold (10 s/slice) scans. The liver-scan time for each study was determined. Scan initiation ranged from 25 to 80 s. An injection duration (50-100 seconds) was selected. From the contrast volume (2 cc/kg x kg body wt) and injection duration, the injection rate (cc/s) was calculated for each patient. Each study was grouped by injection rate corrected for body weight (cc/kg/min) into: 1.2-1.5, 1.51-2.0, and 2.01-2.4. The aortic/liver attenuation curves were plotted for each group.


RESULTS
Liver-scan time for helical studies was a mean of 26 s, for dynamic, non-breath-hold studies 75 s, dynamic breath-hold scans were 154 s. Injection rates of 1.2-1.5 cc/kg/min produced a scanning interval of 165 s. Injection rates of 1.51-2.0 cc/kg/min produced a scanning interval of 120 s. Injection rates of 2.01-2.4 cc/kg/min produced a scanning interval of 90 s. There was no increase in hepatic attenuation for the injection rates 2.01-2.4 cc/kg/min compared with 1.51-2.0 cc/kg/min. There was one complication related to injection through a central line.


CONCLUSIONS
An injection protocol was determined for helical studies with injection rates of 1.7-2.0 cc/kg/min with initiation at 60 s; for dynamic, non-breath-hold studies with injection rates of 1.5-1.7 cc/kg/min with initiation at 50 s; and for dynamic breath-hold studies with injection rates of 1.2-1.5 cc/kg/min with initiation at 45 s. Power injection was used safely in our population.
Roche
K J
KJ
Department of Radiology, New York University Medical Center/Bellevue Hospital, Room 236, 560 First Avenue, New York, NY 10016, USA.
Genieser
N B
NB
Ambrosino
M M
MM
D000293:Adolescent; D002648:Child; D002675:Child, Preschool; D003287:Contrast Media / Q000008:administration & dosage* / Q000493:pharmacokinetics; D004305:Dose-Response Relationship, Drug; D004334:Drug Administration Schedule; D005260:Female; D006801:Humans; D007223:Infant; D007275:Injections, Intravenous / Q000295:instrumentation*; D008099:Liver / Q000000981:diagnostic imaging*; D008297:Male; D011856:Radiographic Image Enhancement / Q000295:instrumentation*; D014057:Tomography, X-Ray Computed / Q000295:instrumentation*; D014283:Triiodobenzoic Acids / Q000008:administration & dosage* / Q000493:pharmacokinetics
D003287:Contrast Media; D014283:Triiodobenzoic Acids; C054871:ioversol