Head CT: Image quality improvement with ASIR-V using a reduced radiation dose protocol for children

Eur Radiol. 2017 Sep;27(9):3609-3617. doi: 10.1007/s00330-017-4733-z. Epub 2017 Jan 23.

Abstract

Objective: To investigate the quality of images reconstructed with adaptive statistical iterative reconstruction V (ASIR-V), using pediatric head CT protocols.

Methods: A phantom was scanned at decreasing 20% mA intervals using our standard pediatric head CT protocols. Each study was then reconstructed at 10% ASIR-V intervals. After the phantom study, we reduced mA by 10% in the protocol for <3-year-old patients and applied 30% ASIR-V and by 30% in the protocol for 3- to 15-year-old patients and applied 40% ASIR-V.

Results: Increasing the percentage of ASIR-V resulted in lower noise and higher contrast-to-noise ratio (CNR) and preserved spatial resolution in the phantom study. Compared to a conventional-protocol, reduced-dose protocol with ASIR-V achieved 12.8% to 34.0% of dose reduction and showed images of lower noise (9.22 vs. 10.73, P = 0.043) and higher CNR in different levels (centrum semiovale, 2.14 vs. 1.52, P = 0.003; basal ganglia, 1.46 vs. 1.07, P = 0.001; and cerebellum, 2.18 vs. 1.33, P < 0.001). Qualitative analysis showed higher gray-white matter differentiation and sharpness and preserved overall diagnostic quality in the images with ASIR-V.

Conclusions: Use of ASIR-V allowed a 12.8% to 34.0% dose reduction in each age group with potential to improve image quality.

Key points: • It is possible to reduce radiation dose and improve image quality with ASIR-V. • We improved noise and CNR and decreased radiation dose. • Sharpness improved with ASIR-V. • Total radiation dose was decreased by 12.8% to 34.0%.

Keywords: Brain; Computer-assisted methods; Pediatric; Radiation dosage; Radiation protection methods.

Publication types

  • Evaluation Study

MeSH terms

  • Adolescent
  • Brain / diagnostic imaging*
  • Child
  • Child, Preschool
  • Clinical Protocols
  • Female
  • Humans
  • Male
  • Phantoms, Imaging
  • Quality Improvement
  • Radiation Dosage
  • Radiographic Image Interpretation, Computer-Assisted / methods
  • Reproducibility of Results
  • Retrospective Studies
  • Tomography, X-Ray Computed / methods*
  • Tomography, X-Ray Computed / standards