RT Journal Article
SR Electronic
T1 Comparison of Low Energy and Medium Energy Collimators for Thyroid Scintigraphy with <sup>123</sup>I
JF Journal of Nuclear Medicine Technology
JO J. Nucl. Med. Technol.
FD Society of Nuclear Medicine
SP jnmt.121.262517
DO 10.2967/jnmt.121.262517
A1 Yuxin Li
A1 Esther Choi
A1 Artineh Hayrapetian
A1 Emmanuel Appiah-Kubi
A1 Jonathan Gershenson
A1 Nazanin Asvadi
A1 Gholam R. Berenji
YR 2021
UL http://tech.snmjournals.org/content/early/2021/09/27/jnmt.121.262517.abstract
AB 123I thyroid scintigraphy can be performed with either a low energy or medium energy collimator. The high-energy photon emissions from 123I cause septal penetration with scattered photons, which deteriorate image quality. The aim of this study is to evaluate the impact of collimator choice on 123I thyroid scintigraphy in clinical practice. Methods: Forty seven patients who received thyroid planar scintigraphy with both a low energy high resolution (LEHR) collimator and a medium energy (ME) collimator were prospectively recruited using the same imaging protocol. Image quality, collimator sensitivity, and estimation of thyroid size were assessed between LEHR and ME collimators, and were compared with thyroid ultrasonography as the gold standard. Results: Images acquired with the ME collimator demonstrate less scattered background noise, improved thyroid to background contrast, and increased sensitivity in the thyroid gland compared to images acquired by the LEHR collimator. Manual measurement of the thyroid length is more accurate by using the ME collimator. Automatic estimation of the thyroid area size by using the same thyroid cutoff threshold is larger in ME collimator images than in LEHR collimator images. Conclusion: 123I thyroid scintigraphy using the ME collimator generates cleaner images with less background noise and has higher collimator sensitivity for thyroid imaging compared to the LEHR collimator. Different thyroid cutoff threshold should be used to estimate the thyroid area size and volume between low and medium energy collimators.