Scintigraphy of the thyroid The most crucial cues, preparation, and examination schedule

Thyroid scintigraphy is a procedure used to identify thyroid disorders due to its ability to absorb iodine from the body, allowing for the examination of thyroid nodules, goiters, and cancer metastases.

An imaging test called thyroid scintigraphy, also known as an isotopic thyroid examination, measures how well the thyroid tissue has been able to absorb a radioactive substance that has previously been injected into the body (orally or intravenously). A unique gamma camera is used for the examination. This allows for the examination of thyroid tumors and goiters as well as the morphology of the gland and the detection of thyroid tissue outside of the organ.

The radiotracer most frequently used in thyroid scintigraphy is technetium-99m (99m Tc). Iodine-131 (131I) is used less frequently. The patient must take the I-131 capsule orally 24 hours prior to the exam, while the first is given orally or intravenously 1 hour or 15 minutes prior to the examination, respectively.

Together with thyroid scintigraphy, the assessment of iodine uptake of this gland, i.e. the degree of iodine uptake after administration of radioactive iodine to the body, is often performed .

Thyroid scintigraphy – indications for examination

Thyroid scintigraphy is performed to:

  • assessment of the size and location of the thyroid gland,
  • thyroid goiter assessment,
  • assessment of thyroid tumor function,
  • differential diagnosis of hyperthyroidism,
  • diagnosis of congenital defects and thyroid disorders,
  • establishing the presence of retrosternal or ectopic goiter,
  • qualification for radioiodine therapy,
  • in suspected thyroid cancer.

Thyroid scintigraphy: how to prepare?

There are some prerequisites for thyroid scintigraphy. The main concern is the potential impact of various variables on the thyroid gland’s ability to absorb radioiodine.

As part of preparation for thyroid scintigraphy, the patient:

  • cannot take for at least 3 weeks before the thyroxine test,
  • at least 5 days earlier should discontinue antithyroid drugs,
  • up to 8 weeks before the examination, should not undergo a test with intravenous contrast agent with iodine,
  • before the examination, he should avoid food with a high content of iodine (e.g. sea fish, algae, supplements or medicines),
  • you should tell your doctor if you think you may be pregnant and if you are breast-feeding.

Thyroid scintigraphy

The process appears slightly different depending on which isotope is used. The patient must take the capsule containing radioisotope 131I 24 hours prior to the test if it is used. You will receive technetium right before the test if it’s necessary, which is more often the case. The primary imaging process lasts a short time. During this time, the patient remains motionless. You don’t need to be completely empty before the exam.

Thyroid scintigraphy: interpretation of results

The specialist can determine the cause of thyroid disorders (such as a picture typical of Graves’ disease or Hashimoto’s disease) and assess the changes based on the image of the radioisotope distribution.

 It is possible to gauge the level of iodine accumulation during thyroid scintigraphy. Based on this, “hot” and “cold” focal lesions (thyroid nodules) can be distinguished. The radioisotope is more strongly captured by “hot” nodules than by other tissues. These changes are typically benign. These primarily consist of adenomas. It is crucial to note that the identified “hot” nodules turn out to be cancerous lesions in about 5% of cases.

“Cold” nodules capture the isotope poorly and may be:

  • cysts,
  • malignant tumors,
  • abscesses,
  • inflammatory foci,
  • hematoma,
  • lymph node.

In the case of the diagnosis of “cold” nodules during scintigraphy, it is recommended to perform additional diagnostics in the form of thyroid ultrasound as well as a thyroid biopsy .

Recommendations after the examination

You can resume your regular activities right away after the thyroid scintigraphic examination. However, it is advised to drink a lot of water (roughly 1.5 liters) right away following the test to flush out the radioisotope’s remnants.

Thyroid scintigraphy: contraindications

Thyroid scintigraphy is a safe examination, but it should not be used in pregnant and lactating women . During the scintigraphic examination, the patient is exposed to small amounts of radiation.


Salt iodization and Hashimoto’s disease. Is it worth supplementing iodine?

Does Salt Iodization Cause Hashimoto’s Disease?

When we buy salt, we often reach for the one with the note "iodized". This means that iodine has been added to the salt – a microelement necessary for the proper functioning of the body. Both deficiency and excess of this element have serious health consequences, especially the thyroid gland. Many people are concerned that eating salt with added iodine leads to Hashimoto’s disease. Is it true?

Significant iodine deficiency causes hypothyroidism, including its most common form – Hashimoto’s disease. Long-term exposure to large amounts of iodine can also lead to Hashimoto’s disease. Excess of this element primarily promotes enlargement of the thyroid gland, hyperthyroidism of this gland and increases the risk of developing thyroid cancer. So it turns out that the most important thing in iodine intake is to maintain the "golden mean".

We get iodine from the environment and through the diet: it is present in the air, water, plants and animals that we eat. The problem is that its amount is not evenly distributed in the environment. Our areas are not very rich in this element. Therefore, in order to improve the health of Poles, in 1997 the obligation to iodize table salt was introduced . It is salt intended for use in households (the obligation does not apply to many types of salt, e.g. Himalayan salt, sea salt, so read the labels, and salt used in the food industry).

Does iodizing salt cause Hashimoto’s disease?

This is a popular myth. Iodizing table salt does not provide so much element to the body to cause any harm. Although excess iodine can actually promote the development of Hashimoto’s disease or worsen its course, as research shows. This applies mainly to people who are genetically predisposed to develop the disease, especially with selenium deficiency. Polish experts agree that the benefits of a common salt iodization program outweigh the possible risks.

Is it worth supplementing iodine?

If hypothyroidism is not caused by iodine deficiency, there is no need for supplementation of this element. Do not take high doses of iodine, Lugol’s liquid or other preparations with iodine without consulting a doctor.

The daily requirement for iodine is:

  • children up to 5 years of age: 90 μg,
  • children 6-12 years: 120 μg,
  • children > 12 and adults: 150 μg,
  • pregnant and lactating women: 250 μg.

A simple way to check the level of this microelement in the body is to test urine for iodine concentration (in healthy people , 90% is excreted by the kidneys). In adults, urinary excretion of iodine should not be lower than 100 micrograms per liter and not higher than 200-300 micrograms per liter.

Do we take the right amount of iodine with our diet?

Table salt is the main source of iodine in the diet. One teaspoon of iodized salt (5 g) contains about 150 micrograms of potassium iodide. Iodine constitutes about 77% of potassium iodide, so this amount does not meet the daily requirement of an adult, but the source of iodine is also a diet. Algae, sea fish, seafood, as well as plants that grew in the soil with a high content of iodine contain a lot of this element (the closer to the sea, the more iodine; the least element occurs in mountainous areas). Remember that you should not overdo it with salt. The WHO recommends limiting its consumption to 5 g per day…

Everything indicates that many people are at risk of iodine deficiency. According to the Krakow declaration on iodine signed in 2018 by scientists from 27 countries, iodine deficiencies occur almost throughout Europe. Children, pregnant women and pregnant women are particularly exposed to them. Scientists postulate in the document that governments should also introduce the obligation to add iodine to industrial salt used as an additive to food products.

What salt should I use for Hashimoto’s disease?

Nutritionists currently recommend that you choose iodized salt regardless of whether you have Hashimoto’s disease or not. According to the research of the Institute of Institute, a diet without iodized salt provides too little iodine in relation to the recommended standards and increases the risk of deficiencies of this element.

Since the introduction of the obligation to iodize salt, the number of goiter of the thyroid gland and the incidence of thyroid cancer has decreased significantly. Of course, it is worth remembering not to exceed the recommended amount of salt, because its excess also promotes other diseases, e.g. hypertension. A reasonable approach seems to be to check the level of iodine in the body, as well as consult an endocrinologist who can professionally assess our need for additional iodine.

Thyroid : Untreated Hashimoto’s disease can lead to male fertility impairment and infertility.

Men are five times less likely than women to get Hashimoto’s disease, according to statistics. Experts believe this is due to testosterone, which “protects” the male body from thyroid problems. If the level of testosterone in the male body declines for any cause, the probability of having Hashimoto’s disease increases.

Learn more at Munaeem’s blog

Fatigue, feeling cold and dry skin are symptoms of hypothyroidism (underactive thyroid)

The thyroid gland is placed in the front center of the neck, between the trachea and the larynx. It is the organ that produces the hormones triiodothyronine (T3), thyroxine (T4), and calcitonin. The thyroid requires iodine from the diet and the environment to manufacture it. The pituitary gland produces the hormone TSH, which regulates thyroid function.

learn more What are the risks of untreated hypothyroidism (Thyroid) ?

Hypothyroidism (hypothyroidism) is a group of symptoms caused by a thyroid gland hormone production. Women are more commonly affected; hypothyroidism is predicted to affect 5% of women and 1% of men. 1-6% of patients are under the age of 60, and the frequency increases with age.

Thyroid hormones affect many different processes and organs throughout the body, including:

  • metabolism,
  • energy use,
  • muscular strength,
  • fertility and potency,
  • heart work,
  • the functioning of the nervous system,
  • mental well-being,
  • condition of skin, hair and nails.

Thyroid hormone insufficiency thus has a negative impact on several bodily systems. Adults and children alike can become ill.

Hypothyroidism: causes

Hypothyroidism can be caused by a number of factors. They might be primary (induced by thyroid gland injury) or secondary (resulting from abnormalities in the functioning of the pituitary gland or hypothalamus):

Primary causes of hypothyroidism  are:

  • Hashimoto’s disease, otherwise chronic autoimmune thyroiditis,
  • postpartum thyroiditis,
  • radioiodine treatment,
  • neck radiotherapy,
  • significant iodine deficiency,
  • the use of certain medications (so-called drug-induced hypothyroidism), e.g. lithium salts, interferon, amiodarone,
  • surgical removal of the thyroid gland,
  • damage to the thyroid gland as a result of a disease, e.g. cancer,
  • congenital hypothyroidism.

Causes of secondary hypothyroidism  include

  • hypothalamic or pituitary tumors,
  • injury or inflammation in the hypothalamus or pituitary gland,
  • Sheehan’s syndrome
  • neurological disorders in which there is a deficiency of nerve impulses that stimulate the pituitary gland and hypothalamus to produce thyroid hormones.

It should be added that iodine deficiency is an increasingly rare cause of the development of hypothyroidism, because iodine deficiencies in the diet are less frequent than in the past.

Hypothyroidism: symptoms

The main symptoms of hypothyroidism are:

  • constant fatigue – inadequate to the effort,
  • drowsiness that does not go away despite drinking coffee or energy drinks,
  • problems with concentration and memory , and even memory loss or intellectual disorders that resemble dementia,
  • muscle weakness,
  • chronic  constipation ,
  • mood swings – especially despondency, indifference,  depression , apathy,
  • feeling cold – even when he is warmly dressed or in heated rooms,
  • decreased sweating, 
  • swelling of the face, eyelids, hands, resulting from the accumulation of mucous substance in the intercellular spaces (myxoedema),
  • pain, redness and burning of the eyes – the symptoms often resemble conjunctivitis,
  • decrease in immunity – the result is frequent infections,
  • problems with getting pregnant  or carrying it to term,
  • easy bruising,
  • tingling and numbness of the hands,
  • hair loss, paleness and dry skin.

Treatment of hypothyroidism

The oral administration of synthetic hormones is used to treat hypothyroidism. The treatment consists of taking levothyroxine, a medicine that is believed to compensate for a lack of the thyroid hormone thyroxine. Endocrinologists typically start youngsters on large doses. Individual dosages of the hormone are determined in adults. Levothyroxine is taken on an empty stomach every morning. Then you should not eat for 30-60 minutes.

Thyroid medications are frequently prescribed for life. Thankfully, the therapy produces positive results: most of the symptoms of hypothyroidism disappear, and there are no side effects. The treatment of hypothyroidism is highly effective. Many symptoms vanish in a matter of minutes. 

Regrettably, some people continue to have symptoms of the condition despite treatment. It is critical to maintain good health in order for therapy to be effective. TSH and, in some situations, T4 levels should be checked on a regular basis, as directed by your doctor.

Inflammation of the thyroid gland: investigations and diagnosis

To determine the cause of thyroid gland inflammation, the doctor will first conduct a thorough interview with the patient to gather medical history. An important point here is the occurrence of symptoms. They can provide valuable information to the doctor about the type of thyroid inflammation. Information from the past, such as a sore throat, radiation therapy, drug therapy, or injury, can also be useful.

A physical examination and the drawing of a blood sample come next. When inflammation values (such as C-reactive protein and blood sedimentation rate) are elevated, the latter can quickly confirm the suspicion of a thyroid gland inflammation. Acute thyroiditis results in an increase in white blood cell count, but subacute thyroiditis does not.

The thyroid hormone levels are also measured. In this way, the doctor can determine whether the thyroid gland is overactive or underactive. You can read more about this in the article Thyroid values .

Ultrasound is a crucial imaging technique when thyroid inflammation is suspected (sonography). On ultrasound, an inflamed thyroid gland will appear dark and have a loose structure (a healthy thyroid gland will appear more uniform). A smaller-than-normal thyroid gland is a symptom of Hashimoto’s thyroiditis.

The physician performs a fine-needle biopsy on the thyroid gland to obtain tissue samples for a more thorough examination. Under a microscope, the typical Langhans’ giant cells can be seen in the case of subacute Quervain thyroiditis.

If necessary, further examinations are carried out, for example, an antibody determination in suspected autoimmune thyroid inflammation (such as Hashimoto’s thyroiditis) or a scintigram.

Thyroiditis: treatment

Antibiotics are used to treat acute purulent (bacterial) inflammation of the thyroid gland. A cooling pad, such as an ice tie, can ease the discomfort. Drugs like acetylsalicylic acid and diclofenac also have an anti-inflammatory and pain-relieving effect. Pus must be removed from an abscess that has developed in the thyroid gland as a result of the inflammation through a puncture or surgical procedure.

Acute non-purulent thyroid gland inflammation that occurs after radiation therapy typically goes away on its own. Anti-inflammatory medications are given to patients when they are in pain. De Quervain thyroiditis that is subacute almost always resolves on its own. In severe cases, cortisone medications like prednisolone and anti-inflammatory medications like acetylsalicylic acid may be administered.

Usually mild and not requiring treatment, postpartum thyroiditis. Thyroid hormones are used if the inflammation resulted in hypothyroidism. Beta blockers may be administered for transient hyperfunction.

The treatment for drug-induced thyroid inflammation depends on the underlying dysfunction: When the thyroid is underactive, thyroid hormones are administered. A low-iodine diet, surgical thyroid gland removal, or radioiodine therapy are all options for treating hyperfunction, depending on its severity. If amiodarone is to blame for the thyroid inflammation, the medication should be stopped as soon as possible.

Inflammation of the thyroid gland: course of the disease and prognosis

With the right care, acute thyroid inflammation completely resolves. However, hypothyroidism may manifest either temporarily or permanently if the inflammation has severely damaged the thyroid tissue. In about 80% of cases, subacute de Quervain thyroiditis resolves spontaneously within three to six months. Rarely does hypothyroidism develop, necessitating the administration of thyroid hormones. 

Silent thyroiditis typically resolves on its own. Additionally, post-partum thyroiditis typically resolves naturally. However, in some patients, the hypothyroidism is persistent and needs to be treated with thyroid hormones. The drug may be discontinued on a trial basis after approximately six months. 

Within a year of giving birth, thyroid function returns to normal for the majority of women. However, chronic thyroid inflammation, specifically Hashimoto’s thyroiditis, develops in about 10% of cases of post-partum thyroiditis. Following post-partum thyroiditis, the risk of goiter (goiter) in the thyroid also rises. Therefore, those who are affected should routinely have their thyroid levels checked by a physician. Additionally, there is a high likelihood that postpartum thyroiditis will return following a subsequent pregnancy.

%d bloggers like this: