title: Quality of abdominal computed tomography angiography: hand versus mechanical intravenous contrast administration in children.
abstract: BACKGROUND
  Abdominal CT angiography has been increasingly used for evaluation of various conditions related to abdominal vasculature in the pediatric population. However, no direct comparison has evaluated the quality of abdominal CT angiography in children using hand versus mechanical administration of intravenous (IV) contrast agent.
  
  
  OBJECTIVE
  To compare hand versus mechanical administration of IV contrast agent in the quality of abdominal CT angiography in the pediatric population.
  
  
  METHODS
  We retrospectively reviewed the electronic medical record to identify pediatric patients (≤18 years) who had abdominal CT angiography between August 2012 and August 2013. The information obtained includes: (1) type of administration of IV contrast agent (hand [group 1] versus mechanical [group 2]), (2) size (gauge) of IV catheter, (3) amount of contrast agent administered and (4) rate of contrast agent administration (ml/s). Two reviewers independently performed qualitative and quantitative evaluation of abdominal CT angiography image quality. Qualitative evaluation of abdominal CT angiography image quality was performed by visual assessment of the degree of contrast enhancement in the region of interest (ROI) based on a 4-point scale. Quantitative evaluation of each CT angiography examination was performed by measuring the Hounsfield unit (HU) using an ROI within the abdominal aorta at two levels (celiac axis and the inferior mesenteric artery) for each child. Analysis of variance (ANOVA) using the F-test was applied to compare contrast enhancement within the abdominal aorta at two levels (celiac axis and inferior mesenteric artery) between hand administration and mechanical administration of IV contrast methods with adjustment for age.
  
  
  RESULTS
  We identified 46 pediatric patients (24 male, 22 female; mean age 7.3 ± 5.5 years; range 5 weeks to 18 years) with abdominal CT angiography performed during the study period. Of these patients, 16 (35%; 1.7 ± 2.2 years; range 5 weeks to 5 years) had hand administration of IV contrast agent and 30 (65%; 10.2 ± 4.2 years; range 4-18 years) had mechanical administration of IV contrast agent. All 46 abdominal CT angiography studies were of diagnostic quality based on qualitative evaluation (all ≥3). All abdominal CT angiography studies from both groups showed diagnostic quality of contrast enhancement (>150 HU) at both the celiac axis and the inferior mesenteric artery (IMA) levels. The contrast enhancement of the abdominal aorta was not significantly different between the IV contrast administration methods at either the celiac axis level (360 ± 158 vs. 353 ± 116, P = 0.24) or the IMA level (340 ± 140 vs. 351 ± 90, P = 0.27), adjusting for age.
  
  
  CONCLUSIONS
  Diagnostic-quality abdominal CT angiography can be achieved using hand administration of IV contrast agent in infants and young children (≤5 years).
authors.affiliation: Department of Radiology, Boston Children's Hospital and Harvard Medical School, 300 Longwood Ave., Boston, MA, 02115, USA.
authors.forename: Rama S
authors.initials: RS
authors.lastname: Ayyala
authors.affiliation: Departments of Anesthesiology and Surgery, Boston Children's Hospital and Harvard Medical School, Boston, MA, USA.
authors.forename: David
authors.initials: D
authors.lastname: Zurakowski
authors.affiliation: Department of Radiology, Boston Children's Hospital and Harvard Medical School, 300 Longwood Ave., Boston, MA, 02115, USA. Edward.Lee@childrens.harvard.edu.
authors.forename: Edward Y
authors.initials: EY
authors.lastname: Lee
mesh_terms: D000005:Abdomen / Q000098:blood supply*; D000293:Adolescent; D057785:Catheters; D002648:Child; D002675:Child, Preschool; D003287:Contrast Media / Q000008:administration & dosage*; D005260:Female; D006801:Humans; D007223:Infant; D007275:Injections, Intravenous / Q000379:methods; D007479:Iopamidol / Q000008:administration & dosage*; D008297:Male; D011856:Radiographic Image Enhancement; D011860:Radiography, Abdominal; D015203:Reproducibility of Results; D012189:Retrospective Studies; D014057:Tomography, X-Ray Computed
chemical_list: D003287:Contrast Media; D007479:Iopamidol
keywords: Abdomen; Bolus tracking; Children; Computed tomography angiography; Contrast; Contrast enhancement; Hand injection; Mechanical injection