Feline hyperthyroidism. The contribution of nuclear medicine.

This paper overviews the incidence, aetiology, clinical signs and complications of hyperthyroidism in cats as well as the contribution of nuclear medicine in the diagnosis and management of this veterinary disease. Thyroid gland scintigraphy is of particular value in detecting autonomic adenoma in occult cases of fenile hyperthyroidism (FH), particularly when hormone tests are doubtful or conflicting. Also, thyroid scintigraphy is useful in detecting the shape of the thyroid gland, hyperfunctioning accessory or ectopic thyroid tissue, multi-nodular goitre and unilateral or bilateral cold lesions. Quantitative radioiodine uptake measurements of 131I, 123I or 99mTc-pertechnetate are rarely performed. Radioiodine uptake is often examined in occult FH. Radioiodine treatment is considered to be the easiest, the most effective and with fewer complications treatment for FH compared to thyreostatic drugs or surgical treatment. The contribution of nuclear medicine in FH is an interesting challenge for both veterinary and nuclear medicine.