1000 radioactive cats.

This handsome cat has hyperthyroidism, a condition which can be very serious and often eventually fatal. There are several ways of treating the disease, which is very very common in cats in Britain.

The most successful treatment is to give radioactive iodine to the cats using a radioactive isotope of iodine, I131. Hyperthyroidism is caused by a benign, but physiologically active, tumour of the thyroid gland. Iodine is stored by the body in active thyroid tissue because iodine is a substrate required for the manufacture of thyroid hormone, T4. If a cat with hyperthyroidism is injected with I131 that radioactive iodine is stored inside the tumour tissue. The radioactivity from the isotope destroys the tumour cells but also disappears quickly from the body so each treated cat is radioactive for only a few days but the thyroid disease is cured (in more than 95% of cases).

In our practice we treated this cat with I131 this week. He is the 1,000th cat we have treated in this way - which makes our centre the most experienced site in the UK for the treatment of hyperthyroid cats in this way.

I131 is a rare example of radiation use as a magic bullet in medicine which very selectively and safely destroys the diseased tissue whilst sparing healthy tissues nearby. Radiation, like many things, can be horribly destructive and dangerous but like many others it can also be used to good ends.

I give you a toast: "to radioactive iodine..."