TITLE:
Correlation between 99mTcO4- Thyroid Scintigraphy and Blood Test in Primary Hyperthyroidism
AUTHORS:
Yukinori Okada, Shoichiro Matsushita, Keiichiro Yamaguchi
KEYWORDS:
Graves’ Disease/Basedow’s Disease, 99mTcO4- Thyroid Scintigraphy, Free T3, Free T4, TSH
JOURNAL NAME:
Open Journal of Endocrine and Metabolic Diseases,
Vol.11 No.3,
March
19,
2021
ABSTRACT: Background: The 99mTcO4- thyroid scintigraphy is commonly used for hyperthyroidism diagnosis. Uptake value of 99mTcO4- on thyroid scintigraphy is an indicator of hyperthyroidism activity. Although, the correlation between free T3 value and free T4 value is not necessary clear in primary hyperthyroidism. Introduction: This study investigated the correlation between results of blood test and uptake of 99mTcO4- on thyroid scintigraphy in primary hyperthyroidism. Methodlogy: In this retrspective study, uptake was calculated in patients diagnosed with primary hyperthyroidism (Graves’ disease/Basedow’s disease) based on clinical findings, blood tests, thyroid ultrasound, and 99mTcO4- thyroid scintigraphy (uptake ≥3%) at St. Marianna University School of Medicine Hospital between 1 January 2010 and 31 December 2019. This uptake of 99mTcO4- was compared with results of blood tests. Results: Fifty-four consecutively arriving patients at the hospital (12 men, 42 women; mean age 43.0 ± 14.0 years) were selected. Free T3 (n = 54) was 14.6 ± 6.8 pg/mL, free T4 (n = 53) was 5.0 ± 2.3 ng/mL, and uptake on thyroid scintigraphy was 10.0% ± 7.1%. The correlation coefficients were 0.60 (p 99mTcO4-thyroid scintigraphy uptake. Conclusion: In primary hyperthyroidism (Graves’ disease), there is a correlation between free T4 value and 99mTcO4- thyroid scintigraphy uptake, but there is no correlation in patients with high free T4 level.