title: Diagnostic reference ranges for pediatric abdominal CT.
abstract: OBJECTIVE
  To develop diagnostic reference ranges (DRRs) and a method for an individual practice to calculate site-specific reference doses for computed tomographic (CT) scans of the abdomen or abdomen and pelvis in children on the basis of body width (BW).
  
  
  METHODS
  This HIPAA-compliant multicenter retrospective study was approved by institutional review boards of participating institutions; informed consent was waived. In 939 pediatric patients, CT doses were reviewed in 499 (53%) male and 440 (47%) female patients (mean age, 10 years). Doses were from 954 scans obtained from September 1 to December 1, 2009, through Quality Improvement Registry for CT Scans in Children within the National Radiology Data Registry, American College of Radiology. Size-specific dose estimate (SSDE), a dose estimate based on BW, CT dose index, dose-length product, and effective dose were analyzed. BW measurement was obtained with electronic calipers from the axial image at the splenic vein level after completion of the CT scan. An adult-sized patient was defined as a patient with BW of 34 cm. An appropriate dose range for each DRR was developed by reviewing image quality on a subset of CT scans through comparison with a five-point visual reference scale with increments of added simulated quantum mottle and by determining DRR to establish lower and upper bounds for each range.
  
  
  RESULTS
  For 954 scans, DRRs (SSDEs) were 5.8-12.0, 7.3-12.2, 7.6-13.4, 9.8-16.4, and 13.1-19.0 mGy for BWs less than 15, 15-19, 20-24, 25-29, and 30 cm or greater, respectively. The fractions of adult doses, adult SSDEs, used within the consortium for patients with BWs of 10, 14, 18, 22, 26, and 30 cm were 0.4, 0.5, 0.6, 0.7, 0.8, and 0.9, respectively.
  
  
  CONCLUSIONS
  The concept of DRRs addresses the balance between the patient's risk (radiation dose) and benefit (diagnostic image quality). Calculation of reference doses as a function of BW for an individual practice provides a tool to help develop site-specific CT protocols that help manage pediatric patient radiation doses.
authors.affiliation: Department of Radiology, James M. Anderson Center for Healthcare Systems Excellence, Cincinnati Children's Hospital Medical Center, 3333 Burnet Ave, Cincinnati, OH 45229-3039, USA. marilyn.goske@cchmc.org
authors.forename: Marilyn J
authors.initials: MJ
authors.lastname: Goske
authors.forename: Keith J
authors.initials: KJ
authors.lastname: Strauss
authors.forename: Laura P
authors.initials: LP
authors.lastname: Coombs
authors.forename: Keith E
authors.initials: KE
authors.lastname: Mandel
authors.forename: Alexander J
authors.initials: AJ
authors.lastname: Towbin
authors.forename: David B
authors.initials: DB
authors.lastname: Larson
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Callahan
authors.forename: Kassa
authors.initials: K
authors.lastname: Darge
authors.forename: Daniel J
authors.initials: DJ
authors.lastname: Podberesky
authors.forename: Donald P
authors.initials: DP
authors.lastname: Frush
authors.forename: Sjirk J
authors.initials: SJ
authors.lastname: Westra
authors.forename: Jeffrey S
authors.initials: JS
authors.lastname: Prince
mesh_terms: D000293:Adolescent; D016009:Chi-Square Distribution; D002648:Child; D002675:Child, Preschool; D003287:Contrast Media; D005260:Female; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D011829:Radiation Dosage; D011857:Radiographic Image Interpretation, Computer-Assisted; D011860:Radiography, Abdominal / Q000379:methods*; D012016:Reference Values; D012042:Registries; D012189:Retrospective Studies; D014057:Tomography, X-Ray Computed
chemical_list: D003287:Contrast Media