title: The use of adaptive statistical iterative reconstruction in pediatric head CT: a feasibility study.
abstract: OBJECTIVE
  Iterative reconstruction techniques facilitate CT dose reduction; though to our knowledge, no group has explored using iterative reconstruction with pediatric head CT. Our purpose was to perform a feasibility study to assess the use of ASIR in a small group of pediatric patients undergoing head CT.
  
  
  METHODS
  An Alderson-Rando head phantom was scanned at decreasing 10% mA intervals relative to our standard protocol, and each study was then reconstructed at 10% ASIR intervals. An intracranial region of interest was consistently placed to estimate noise. Our ventriculoperitoneal shunt CT protocol was subsequently modified, and patients were scanned at 20% ASIR with approximately 20% mA reductions. ASIR studies were anonymously compared with older non-ASIR studies from the same patients by 2 attending pediatric neuroradiologists for diagnostic utility, sharpness, noise, and artifacts.
  
  
  RESULTS
  The phantom study demonstrated similar noise at 100% mA/0% ASIR (3.9) and 80% mA/20% ASIR (3.7). Twelve pediatric patients were scanned at reduced dose at 20% ASIR. The average CTDI(vol) and DLP values of the 20% ASIR studies were 22.4 mGy and 338.4 mGy-cm, and for the non-ASIR studies, they were 28.8 mGy and 444.5 mGy-cm, representing statistically significant decreases in the CTDI(vol) (22.1%, P = .00007) and DLP (23.9%, P = .0005) values. There were no significant differences between the ASIR studies and non-ASIR studies with respect to diagnostic acceptability, sharpness, noise, or artifacts.
  
  
  CONCLUSIONS
  Our findings suggest that 20% ASIR can provide approximately 22% dose reduction in pediatric head CT without affecting image quality.
authors.affiliation: Department of Radiology, Allegheny General Hospital, Pittsburgh, Pennsylvania, USA.
authors.forename: G A
authors.initials: GA
authors.lastname: Vorona
authors.forename: G
authors.initials: G
authors.lastname: Zuccoli
authors.forename: T
authors.initials: T
authors.lastname: Sutcavage
authors.forename: B L
authors.initials: BL
authors.lastname: Clayton
authors.forename: R C
authors.initials: RC
authors.lastname: Ceschin
authors.forename: A
authors.initials: A
authors.lastname: Panigrahy
mesh_terms: D000465:Algorithms; D001921:Brain / Q000000981:diagnostic imaging*; D002648:Child; D003627:Data Interpretation, Statistical; D005240:Feasibility Studies; D006257:Head / Q000000981:diagnostic imaging*; D006801:Humans; D019047:Phantoms, Imaging; D011856:Radiographic Image Enhancement / Q000379:methods*; D011857:Radiographic Image Interpretation, Computer-Assisted / Q000379:methods*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D014057:Tomography, X-Ray Computed / Q000295:instrumentation / Q000379:methods*