Risks
Scintigraphy of the thyroid gland is a very low-risk examination. The radiation exposure is quite low. Only pregnant women are at risk, as malformations of the child can occur.
Therefore, pregnancy speaks against a scintigraphy. There is no danger for people with a so-called iodine allergy. This is an allergy that is not directed against iodine, but against other components of contrast media containing iodine. However, these are not used in a scintigraphy.
Duration
The scintigraphy of the thyroid gland usually takes no more than half an hour from the injection of the radioactive substance to the completion of the actual measurement. After completion of the measurement, it is important to note that one still emits radioactive radiation for several hours. Close contact with pregnant women, nursing mothers and children should be avoided during this time. By the next day at the latest, the radioactivity has decayed so far and the substances have been excreted in the urine that there is no longer any danger to other people.
Carbimazole
Carbimazole is a drug that inhibits the function of the thyroid gland and thus hormone production. It is used in cases of hyperthyroidism.Due to its influence on thyroid function, it also influences the results of a scintigraphy. Therefore, it should be discontinued a few days before the examination if possible. If the examination is nevertheless performed under the influence of carbimazole, this must be taken into account in the evaluation.
Radiation exposure
Many people are afraid of a thyroid scintigraphy due to the radioactive radiation used. This fear is largely unjustified, since the exposure to radiation is very low during this examination. Our body experiences a low radiation exposure in everyday life anyway.
In some situations it is higher, such as a long-distance flight. There are also regional differences. The additional radiation exposure of a thyroid scintigraphy corresponds approximately to a natural radiation exposure of half a year.
If there is an indication for the examination, the advantages outweigh the small risks. An exception is made for pregnant women, as the possible consequences of radiation exposure would be particularly fatal for the growing child. Therefore, no scintigraphy of the thyroid gland should be performed during pregnancy. In children, advantages and disadvantages must be weighed up, but in principle a scintigraphy can be performed with dosages adapted to age and weight.