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.
PL-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 20.5 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.
Currently, there are no radioactive source inserts available to loan for use with PL-701.
PL-702: Humanoid Systems Neck Phantom
PL-702, PL-703 (nCi) | PL-702, PL-703 (kBq)
The neck phantom is a simulated tissue-substitute thyroid calibration phantom, manufactured by Humanoid Systems (currently Radiology Support Devices, Inc.†). The phantom consists of the neck, containing a simulated bone-equivalent vertebrae, portions of the clavicle and sternum, a hollow-shell thyroid with an internal volume of either 6-8 mL or 16-18 mL, and a front cover of Adiprene muscle-equivalent tissue substitute. Two ports on the thyroid insert allow quick filling and flushing of solutions.
PL-703: RSD Head Phantom
PL-702, PL-703 (nCi) | PL-702, PL-703 (kBq)
The RSD† Head Phantom is similar to the Humanoid neck phantom, but also completes the cervical spine and adds a head. The head is cast around a simulated skull, and contains a foam insert behind the thyroid to simulate air spaces. The same thyroid inserts are available for the head phantom.
†Radiology Support Devices, Inc., 1904 E. Dominguez St., Long Beach CA 90810
| Phantom ID# | Note | Isotope | Calibrated Activity (nCi) | ± | Uncertainty | Calibration Date | Activity (nCi) on 01Jan2007 |
Uncertainty Measure | PNNL Ref# | Order Info |
|---|---|---|---|---|---|---|---|---|---|---|
| PL-806 | A | 133Ba | 3332 | ± | 27 | 4/1/00 | 2155 | Thy491 | PNNL | |
| PL-807 | A | 133Ba | 57.3 | ± | 0.49 | 2/22/01 | 39 | Thy500 | PNNL |
Note A - approx. 18 ml vol, reference male thyroid
| Phantom ID# | Note | Isotope | Calibrated Activity (kBq) | ± | Uncertainty | Calibration Date | Activity (kBq) on 01Jan2007 |
Uncertainty Measure | PNNL Ref# | Order Info |
|---|---|---|---|---|---|---|---|---|---|---|
| PL-806 | A | 133Ba | 123.28 | ± | 1.00 | 4/1/00 | 79.72 | Thy491 | PNNL | |
| PL-807 | A | 133Ba | 2.12 | ± | 0.02 | 2/22/01 | 1.45 | Thy500 | PNNL |
Note A - 18 ml vol, reference male thyroid
