Open AccessA measurement of the attenuation of radiation from F‐18 by a PET/MR scanner
Author(s) -
Wendt Richard E.,
Ai Hua A.,
Meier Joseph G.,
Lopez Benjamin P.,
Fahrenholtz Samuel J.,
Mawlawi Osama R.
Publication year - 2018
Publication title -
journal of applied clinical medical physics
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.83
H-Index - 48
ISSN - 1526-9914
DOI - 10.1002/acm2.12479
Subject(s) - isocenter , scanner , attenuation , correction for attenuation , electromagnetic shielding , nuclear medicine , optics , physics , ionization chamber , radiation , materials science , medicine , imaging phantom , ion , ionization , quantum mechanics
The attenuation of 511 keV photons by the structure of a PET/MR scanner was measured prior to energizing the magnet. The exposure rate from a source of fluorine‐18 was measured in air and, with the source placed at the isocenter of the instrument, at various points outside of the scanner. In an arc from 45 to 135 degrees relative to the long axis of the scanner and at a distance of 1.5 m from the isocenter, the attenuation by the scanner is at least 5.6 half‐value layers from the MR component alone and at least 6.6 half‐value layers with the PET insert installed. This information could inform better design of the radiation shielding for PET/MR scanners.