title: Calibration of Traceable Solid Mock (131)I Phantoms Used in an International SPECT Image Quantification Comparison.
abstract: The International Atomic Energy Agency (IAEA) has organized an international comparison to assess Single Photon Emission Computed Tomography (SPECT) image quantification capabilities in 12 countries. Iodine-131 was chosen as the radionuclide for the comparison because of its wide use around the world, but for logistical reasons solid (133)Ba sources were used as a long-lived surrogate for (131)I. For this study, we designed a set of solid cylindrical sources so that each site could have a set of phantoms (having nominal volumes of 2 mL, 4 mL, 6 mL, and 23 mL) with traceable activity calibrations so that the results could be properly compared. We also developed a technique using two different detection methods for individually calibrating the sources for (133)Ba activity based on a National standard. This methodology allows for the activity calibration of each (133)Ba source with a standard uncertainty on the activity of 1.4 % for the high-level 2-, 4-, and 6-mL sources and 1.7 % for the lower-level 23 mL cylinders. This level of uncertainty allows for these sources to be used for the intended comparison exercise, as well as in other SPECT image quantification studies.
authors.affiliation: National Institute of Standards and Technology, Gaithersburg, MD 20899.
authors.forename: B E
authors.initials: BE
authors.lastname: Zimmerman
authors.affiliation: National Institute of Standards and Technology, Gaithersburg, MD 20899.
authors.forename: L
authors.initials: L
authors.lastname: Pibida
authors.affiliation: National Institute of Standards and Technology, Gaithersburg, MD 20899.
authors.forename: L E
authors.initials: LE
authors.lastname: King
authors.affiliation: National Institute of Standards and Technology, Gaithersburg, MD 20899.
authors.forename: D E
authors.initials: DE
authors.lastname: Bergeron
authors.affiliation: National Institute of Standards and Technology, Gaithersburg, MD 20899.
authors.forename: J T
authors.initials: JT
authors.lastname: Cessna
authors.affiliation: National Institute of Standards and Technology, Gaithersburg, MD 20899 ; Nuclear Engineering and Engineering Physics Program, Rensselaer Polytechnic Institute, Troy, NY 12180.
authors.forename: M M
authors.initials: MM
authors.lastname: Mille
keywords: SPECT; barium-133; iodine-131; standards; traceability