Chen Yen-Kung, Chen Yen-Ling, Cheng Ru-Hwa, Yeh Chia-Lu, Lee Chin-Cheng, Hsu Chung-Huei
Department of Nuclear Medicine and PET Center, Shin Kong Wu Ho-Su Memorial Hospital, Taipei Medical University, Taipei, Taiwan.
Nucl Med Commun. 2007 Feb;28(2):117-22. doi: 10.1097/MNM.0b013e328013eaf7.
To evaluate the significance of bilateral fluorodeoxyglucose (FDG) uptake in the thyroid glands.
Bilateral thyroid FDG uptake, defined as visualization of thyroid glands, was found in 66 (3.4%) of 1925 subjects who underwent our FDG PET cancer-screening program. Additionally, 16 of the 41 patients with Graves' disease and hyperthyroidism (GD(H)) and six of the 20 subjects with Graves' disease and euthyroidism (GD(E)), who had FDG uptake in thyroid glands, were enrolled in this study.
Among the 66 subjects, 22 were normal variant, 39 subjects had chronic thyroiditis (35 subjects presented with diffuse goitre and four with multinodular goitre), and five subjects had multinodular goitre (MNG) without chronic thyroiditis. Fourteen of 22 (63.6%) of the subjects with the normal variant had a visual uptake intensity less than that of the liver, while 30 of 39 (76.9%) of the subjects with chronic thyroiditis and 14 of 22 (63.6%) of the subjects with Graves' disease had visual uptake intensity greater than or equal to liver uptake. Two of the five subjects with MNG with focally intense uptake were proven to have thyroid carcinoma. Bilateral loser uptake in thyroids associated with thymus and symmetrical skeletal muscle uptake were found in GD(H). The standard uptake value (SUV) (mean+/-SD) in subjects with chronic thyroiditis (2.76+/-1.24) were higher, while those with GD(H) (1.59+/-0.36) were lower than that of the normal variant (1.99+/-0.63). Subjects with hypothyroidism (3.04+/-1.39) had higher SUV levels than those subjects with euthyroidism (2.44+/-1.11). In addition, patients with GD(H) had lower levels than those with GD(E) (2.0+/-0.38).
(1) Bilateral thyroidal uptake of FDG can be found in normal variants and subjects with various thyroid disorders, showing varieties of uptake patterns. (2) Diffuse intense uptake and higher SUV levels are a clue to a diagnosis of chronic thyroiditis, especially for those with hypothyroidism. (3) Focally intense uptake suggests the possibility of a thyroid carcinoma. (4) Sparse uptake associated with the thymus and symmetrical skeletal muscle uptake and lower SUV level raise the possibility of Graves' disease with hyperthyroidism.
评估甲状腺双侧氟脱氧葡萄糖（FDG）摄取的意义。
在1925例接受FDG PET癌症筛查项目的受试者中，66例（3.4%）发现甲状腺双侧FDG摄取，定义为甲状腺显影。此外，41例格雷夫斯病伴甲状腺功能亢进（GD(H)）患者中有16例以及20例格雷夫斯病伴甲状腺功能正常（GD(E)）受试者中有6例甲状腺有FDG摄取，纳入本研究。
66例受试者中，22例为正常变异，39例有慢性甲状腺炎（35例表现为弥漫性甲状腺肿，4例为多结节性甲状腺肿），5例有多结节性甲状腺肿（MNG）但无慢性甲状腺炎。22例正常变异受试者中有14例（63.6%）视觉摄取强度低于肝脏，39例慢性甲状腺炎受试者中有30例（76.9%）以及22例格雷夫斯病受试者中有14例（63.6%）视觉摄取强度大于或等于肝脏摄取。5例MNG且有局灶性强化摄取的受试者中有2例被证实患有甲状腺癌。在GD(H)患者中发现甲状腺与胸腺相关的双侧低摄取以及对称性骨骼肌摄取。慢性甲状腺炎患者的标准摄取值（SUV）（均值±标准差）（2.76±1.24）较高，而GD(H)患者（1.59±0.36）低于正常变异者（1.99±0.63）。甲状腺功能减退患者（3.04±1.39）的SUV水平高于甲状腺功能正常患者（2.44±1.11）。此外，GD(H)患者的水平低于GD(E)患者（2.0±0.38）。
（1）正常变异者及各种甲状腺疾病患者均可出现甲状腺双侧FDG摄取，表现出多种摄取模式。（2）弥漫性强化摄取及较高的SUV水平是诊断慢性甲状腺炎的线索，尤其是甲状腺功能减退者。（3）局灶性强化摄取提示甲状腺癌的可能性。（4）与胸腺相关的稀疏摄取以及对称性骨骼肌摄取和较低的SUV水平增加了格雷夫斯病伴甲状腺功能亢进的可能性。
