Author/Authors :
Nishii, Ryuichi Department of Molecular Imaging and Theranostics - National Institute of Radiological Sciences (NIRS) - Anagawa - Inage-ku - Chiba-shi - Chiba, Japan , Nagamachi, Shigeki Department of Radiology - Faculty of Medicine - University of Miyazaki - Kihara - Kiyotake-cho - Miyazaki-shi - Miyazaki, Japan , Mizutani, Youichi Department of Radiology - Faculty of Medicine - University of Miyazaki - Kihara - Kiyotake-cho - Miyazaki-shi - Miyazaki, Japan , Terada, Tamasa Department of Radiology - Faculty of Medicine - University of Miyazaki - Kihara - Kiyotake-cho - Miyazaki-shi - Miyazaki, Japan , Kiyohara, Syogo Department of Radiology - Faculty of Medicine - University of Miyazaki - Kihara - Kiyotake-cho - Miyazaki-shi - Miyazaki, Japan , Wakamatsu, Hideyuki Department of Radiology - Faculty of Medicine - University of Miyazaki - Kihara - Kiyotake-cho - Miyazaki-shi - Miyazaki, Japan , Fujita, Seigo Department of Radiology - Faculty of Medicine - University of Miyazaki - Kihara - Kiyotake-cho - Miyazaki-shi - Miyazaki, Japan , Higashi, Tatsuya Department of Molecular Imaging and Theranostics - National Institute of Radiological Sciences (NIRS) - Anagawa - Inage-ku - Chiba-shi - Chiba, Japan , Yoshinaga, Keiichiro Department of Molecular Imaging and Theranostics - National Institute of Radiological Sciences (NIRS) - Anagawa - Inage-ku - Chiba-shi - Chiba, Japan , Saga, Tsuneo Department of Diagnostic Imaging and Nuclear Medicine - Kyoto University - Graduate School of Medicine - ShogoinKawahara-cho - Sakyo-ku - Kyoto - Kyoto, Japan , Hirai, Toshinori Department of Radiology - Faculty of Medicine - University of Miyazaki - Kihara - Kiyotake-cho - Miyazaki-shi - Miyazaki, Japan
Abstract :
We retrospectively analyzed activated BAT visualization on FDG-PET/CT in patients with various conditions and TH
levels to clarify the relationships between visualization of BAT on FDG-PET/CT and the efect of TH. Methods. Patients who
underwent clinical FDG-PET/CT were reviewed and we categorized patients into 5 groups: (i) thyroid hormone withdrawal (THW)
group; (ii) recombinant human thyrotropin (rhTSH) group; (iii) hypothyroidism group; (iv) hyperthyroidism group; and (v) BAT
group. A total of sixty-two FDG-PET/CT imaging studies in ffy-nine patients were performed. To compare each group, gender;
age; body weight; serum TSH, FT3, and FT4 levels; and outside temperature were evaluated. Results. No signifcant visualization
of BAT was noted in any of the images in the THW, rhTSH, hypothyroidism, and hyperthyroidism groups. All patients in the BAT
group were in a euthyroid state. When the BAT-negative and BAT-positive patient groups were compared, it was noted that the
minimum and maximum temperature on the day of the PET study and maximum temperature of the one day before the PET study
were signifcantly lower in BAT-positive group than in all those of other groups. Conclusions. Elevated TSH condition before RIT,
hyperthyroidism, or hypothyroidism did not signifcantly impact BAT visualization of clinical FDG-PET/CT images.
