Radiological Physics and Technology

, Volume 6, Issue 2, pp 313–316 | Cite as

Where should we measure the entrance air kerma rate during acceptance testing of the automatic dose control of a fluoroscopic system?

  • Atsushi FukudaEmail author
  • Tosiaki Miyati
  • Kosuke Matsubara


In Japan, the entrance air kerma rate (EAKR) to a patient cannot exceed 50 mGy/min in conventional fluoroscopy. However, it is unclear where the EAKR should be measured. We obtained the tube potential and tube current as a function of polymethylmethacrylate (PMMA) thickness, and the EAKR at the interventional reference point (IRP) was measured from the trajectory. The EAKR at the point established by the U.S. Food and Drug Administration (FDA) was calculated from EAKR at the IRP. The EAKR at the IRP exceeded the limit at a PMMA thickness of 22–28 cm. However, the EAKR did not exceed the limit at the FDA point. If the EAKR to a patient is being verified to meet the recent Japanese ruling, the EAKR should be measured at the FDA point, and if the EAKR is being evaluated for determination of the skin dose, it should be monitored at the IRP.


Entrance air kerma to patient Medical law enforcement Acceptance testing IRP FDA point Interventional radiology 


Conflict of interest

The authors declare that we have no conflict of interest in this study.


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Copyright information

© Japanese Society of Radiological Technology and Japan Society of Medical Physics 2013

Authors and Affiliations

  • Atsushi Fukuda
    • 1
    • 2
    Email author
  • Tosiaki Miyati
    • 2
  • Kosuke Matsubara
    • 2
  1. 1.Department of RadiologyShiga Medical Center for ChildrenMoriyama cityJapan
  2. 2.Division of Health SciencesGraduate School of Medical Sciences, Kanazawa UniversityKanazawaJapan

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