Turrel J M, Feldman E C, Hays M, Hornof W J
J Am Vet Med Assoc. 1984 Mar 1;184(5):554-9.
Eleven cats with hyperthyroidism were treated with radioactive iodine (131I). Previous unsuccessful treatments for hyperthyroidism included hemithyroidectomy (2 cats) and an antithyroid drug (7 cats). Two cats had no prior treatment. Thyroid scans, using technetium 99m, showed enlargement and increased radionuclide accumulation in 1 thyroid lobe in 5 cats and in both lobes in 6 cats. Serum thyroxine concentrations were high and ranged from 4.7 to 18 micrograms/dl. Radioactive iodine tracer studies were used to determine peak radioactive iodine uptake (RAIU) and effective and biological half-lives. Activity of 131I administered was calculated from peak RAIU, effective half-life, and estimated thyroid gland weight. Activity of 131I administered ranged from 1.0 to 5.9 mCi. The treatment goal was to deliver 20,000 rad to hyperactive thyroid tissue. However, retrospective calculations based on peak RAIU and effective half-life obtained during the treatment period showed that radiation doses actually ranged from 7,100 to 64,900 rad. Complete ablation of the hyperfunctioning thyroid tissue and a return to euthyroidism were seen in 7 cats. Partial responses were seen in 2 cats, and 2 cats became hypothyroid. It was concluded that 131I ablation of thyroid tumors was a reasonable alternative in the treatment of hyperthyroidism in cats. The optimal method of dosimetry remains to be determined.
11只患有甲状腺功能亢进的猫接受了放射性碘（131I）治疗。先前治疗甲状腺功能亢进失败的方法包括甲状腺半切除术（2只猫）和抗甲状腺药物治疗（7只猫）。2只猫未接受过先前治疗。使用锝99m进行的甲状腺扫描显示，5只猫的1个甲状腺叶增大且放射性核素积累增加，6只猫的两个甲状腺叶均如此。血清甲状腺素浓度较高，范围为4.7至18微克/分升。放射性碘示踪研究用于确定放射性碘摄取峰值（RAIU）以及有效半衰期和生物半衰期。根据RAIU峰值、有效半衰期和估计的甲状腺重量计算给予的131I活度。给予的131I活度范围为1.0至5.9毫居里。治疗目标是向功能亢进的甲状腺组织输送20,000拉德的辐射剂量。然而，根据治疗期间获得的RAIU峰值和有效半衰期进行的回顾性计算表明，实际辐射剂量范围为7,100至64,900拉德。7只猫的功能亢进甲状腺组织完全消融并恢复至甲状腺功能正常。2只猫出现部分反应，2只猫出现甲状腺功能减退。得出的结论是，131I消融甲状腺肿瘤是治疗猫甲状腺功能亢进的一种合理替代方法。剂量测定的最佳方法仍有待确定。
