Individualized kV selection and tube current reduction in excretory phase computed tomography urography: potential for radiation dose reduction and the contribution of iterative reconstruction to image quality

J Comput Assist Tomogr. Jul-Aug 2013;37(4):551-9. doi: 10.1097/RCT.0b013e31828f871f.

Abstract

Objective: The objective of this study was to analyze radiation dose reduction and image quality by combining automated kV selection, tube current reduction, and iterative reconstruction.

Methods: This was a retrospective analysis of the excretory phase of 55 patients with 2 computed tomography urography examinations: automated kV selection with tube current reduction ("low-dose protocol": with filtered back projection vs iterative reconstruction) and routine dose examinations. Image quality was analyzed blindly and in side-by-side analyses, in addition to quantitative measurements.

Results: Low-dose protocol median dose change was -40% (-10.7 to +12.9 mGy); 100 kV was autoselected in 44 (80%) of 55 patients (body mass index range, 19-36 kg/m) with mean dose reduction of 42.5%. Whereas up to 19% of low-dose images with filtered back projection were inferior by blinded review (P < 0.001), low-dose iterative reconstruction images were not rated inferior (P = 1.0).

Conclusions: The combination of iterative reconstruction, automated kV selection, and tube current reduction results in radiation dose reduction with preserved image quality and diagnostic confidence.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Aged
  • Aged, 80 and over
  • Algorithms
  • Female
  • Humans
  • Male
  • Middle Aged
  • Radiation Dosage*
  • Radiation Protection / methods*
  • Radiographic Image Enhancement / methods*
  • Radiographic Image Interpretation, Computer-Assisted / methods*
  • Reproducibility of Results
  • Retrospective Studies
  • Sensitivity and Specificity
  • Tomography, X-Ray Computed / methods*
  • Urination*
  • Urography / methods*