Thyroid uptake and scintigraphy using 99mTc pertechnetate: standardization in normal individuals.
BACKGROUND
Thyroid uptake and scintigraphy using 99mTc-pertechnetate has proven to be more advantageous than with 131I-iodide, since the images have better quality, the procedure is faster and the patient is submitted to a lower radiation dose.


OBJECTIVE
The purpose of this study was to standardize a simple and fast methodology for performing thyroid uptake and scintigraphy and to determine the normal values for 99mTc- pertechnetate uptake.


METHODS
Prospective, non-randomized.


METHODS
Division of Nuclear Medicine, Department of Radiology, School of Medical Sciences, Campinas State University.


METHODS
The study consisted of 47 normal individuals, 30 women and 17 men, with ages ranging from 19 to 61 years (mean of 33 years).


METHODS
The laboratory assessment of thyroid function consisted of serum dosages of ultra-sensitive thyroxin and thyrotrophin. Twenty minutes after an intravenous injection of 10 mCi (370 MBq) of 99mTc-pertechnetate, the images were obtained on a computerized scintillation camera equipped with a low-energy high-resolution parallel hole collimator.


RESULTS
All the individuals were euthyroid both on clinical and laboratory evaluation. The baseline thyroid 99mTc-pertechnetate uptake ranged from 0.4 to 1.7%. The uptake values obtained in these normal individuals showed that 95% presented a thyroid uptake that ranged from 0.4 to 1.5% of the injected dose.


CONCLUSIONS
The assessment of thyroid structure and function using 99mTc-pertechnetate is a simple, fast and efficient method, which could easily become a part of the routine studies in nuclear medicine laboratories.
Ramos
Celso Darío
CD
Division of Nuclear Medicine, Department of Radiology, School of Medical Sciences, Campinas State University, Campinas, Brazil. cdramos@mn-d.com
Zantut Wittmann
Denise Engelbrecht
DE
Etchebehere
Elba Cristina Sá de Camargo
EC
Tambascia
Marcos Antonio
MA
Silva
Cleide Aparecida Moreira
CA
Camargo
Edwaldo Eduardo
EE
D000328:Adult; D000368:Aged; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D011877:Radionuclide Imaging; D019275:Radiopharmaceuticals; D012015:Reference Standards; D013670:Sodium Pertechnetate Tc 99m; D013960:Thyroid Function Tests / Q000592:standards; D013961:Thyroid Gland / Q000000981:diagnostic imaging*; D013972:Thyrotropin / Q000097:blood*; D013974:Thyroxine / Q000097:blood*
D019275:Radiopharmaceuticals; D013972:Thyrotropin; D013670:Sodium Pertechnetate Tc 99m; D013974:Thyroxine