Broome MR, Donner GS.
This report describes the use of 99mtechnetium pertechnetate (99mTcO4−) and 131[for imaging of a metastatic thyroid carcinoma in a dog. The 131] imaging showed metastatic lesions undetected by the 99mTcO4− imaging on 2 separate occasions. The possible mechanisms for the discrepancies between 131I and 99mTcO4− imaging of thyroid carcinomas are discussed. The use of 131I for the imaging of functional thyroid carcinomas in the dog is recommended.