Assessment of Patient Dose from CT Examinations in Khorasan, Iran

Document Type: Original Paper

Authors

1 Medical Physics Research Center, School of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran Department of Medical Physics, School of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran

2 Department of Medical Physics, School of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran

Abstract

Introduction
Computed Tomography scans are a very important tool for diagnosis and assessment of response to treatment in the practice of medicine. Ionizing radiation in medical imaging is undoubtedly one of the most powerful diagnostic tools in medicine. Yet, as with all medical interventions, there are potential risks in addition to the clear potential benefits.
Materials and Methods
Two reference dose quantities have been defined in order to promote the use of good technique in CT. These are weighted CT dose index (CTDIw) in (mGy) for a single slice in serial scanning or per rotation in helical scanning, and dose–length product (DLP) per complete examination (mGy.cm), All measurements were performed using a pencil shaped ionization chamber introduced into polymethyl methacrylate cylindrical brain and body phantoms. This survey was performed on 7 CT scanners in Khorasan Province-Iran.
Results
DLP for brain, chest, abdomen and pelvic examinations had a range of 255 - 1026, 76-1277, 48-737, 69-854 mGy.cm, respectively.
Conclusion
The results obtained in this study show that the DLP values obtained in this province are lower than European Commission reference dose levels (EC RDL), in other words performance of all the scanners were satisfactory.

Keywords

Main Subjects


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Volume 9, Issue 4
November and December 2012
Pages 233-238
  • Receive Date: 18 July 2012
  • Revise Date: 16 March 2013
  • Accept Date: 17 November 2012