Thyroid Calibration Phantoms
The phantom library maintains three types of thyroid calibration phantoms for use in iodine or mock-iodine thyroid measurement calibrations. The three types of thyroid phantoms are the ANSI (ANSI N44.3 1973) neck phantom, a Humanoid Systems neck phantom, and a Radiology Support Devices (RSD) head phantom. Each phantom can be used for calibrations of iodine radionuclides, or mock-iodine radionuclides such as 133Ba.
RESL-701: ANSI Standard Thyroid Uptake Neck Phantom
This solid right-circular cylinder is composed of acrylic (PMMA) and contains one cutout for a 30 mL bottle containing radioactive source material. Manufactured by Nuclear Associates, it conforms to the specifications of ANSI N44.3. The vial simulates a 30 g. Reference Man thyroid mass when inserted into the phantom. While the phantom has very few anthropomorphic features, it performs with reasonable accuracy for 131I and within 25%-50% for contact measurements for 125I. The Lucite material has a mass attenuation coefficient at 30 keV of 0.303 cm2/g compared to the ICRU 46 tissue value of 0.0.361 cm2/g.
Radioactive source inserts are available upon request to loan for use with RESL-701.