Measurement of the dose index in a 320 detector row CT scanner
Keywords:
Computed Tomography (TC), Computed Tomography Dose Index (CTDI), radiation thickness, phantomAbstract
The purpose of this article is to show part of the tests realized in the acceptance of the Canon Aquilion One TC, which has 320 rows of detectors that allow make acquisitions with a slice thickness up to 160 mm, very useful in pediatric patient examinations. The common tests of the PECCR are contemplated to be performed on scanners with smaller slice thicknesses, so there are proposed other methods for evaluating CTDI in cases that radiation thickness is greater than the radiation detector used in quality controls. Differences have been observed between the methods of up to 12% in less than 80 mm of thickness cases and up to 20% in the largest thickness. In addition, an evaluation of the new metric “equilibrium dose” is made on the 600 mm long phantom TG200, obtaining results that agree with the bibliography. It is proposed a longitudinal dose profile evaluation method for an axial acquisition with radiochromic.
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