Guidelines for Appropriate CT Imaging

  • Kristie M. Guite
  • J. Louis Hinshaw
  • Frank N. Ranallo
  • Fred T. Lee
Part of the Medical Radiology book series (MEDRAD)


Computed Tomography (CT) is now used to diagnose or guide management of virtually every disease state. However, this increase in CT use is associated with a rapid increase in medical radiation exposure. In response, there has been increased emphasis on reducing the radiation exposure associated with CT. This includes both using alternate imaging modalities and optimizing the technical parameters of the CT scans that are performed. An insidious and often overlooked source of medical radiation exposure is multiphasic examinations. Multiple CT phases (before and after contrast administration, delayed imaging, and venous and arterial phases among others) can be highly useful for certain specific clinical indications. However, when used incorrectly, multi-phase examinations multiply radiation dose for no benefit. In response to the need for guidelines for appropriate CT use, the American College of Radiology has created appropriateness criteria to provide guidance regarding the most efficacious use of multi-phase CT.


Portal Venous Phase Arterial Phase Imaging Compute Tomography Urography Excretory Phase Compute Tomography Enterography 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.



Computed tomography






Computed tomography angiography


Computed tomography urography


Magnetic resonance imaging


American college of radiology


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Copyright information

© Springer-Verlag Berlin Heidelberg 2012

Authors and Affiliations

  • Kristie M. Guite
    • 1
  • J. Louis Hinshaw
    • 1
  • Frank N. Ranallo
    • 1
    • 2
  • Fred T. Lee
    • 1
  1. 1.Departments of RadiologyUniversity of WisconsinMadisonUSA
  2. 2.Departments of Medical PhysicsUniversity of WisconsinMadisonUSA

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