Goiter

What is the thyroid gland and where is it located?

The largest cartilage that forms the larynx was named thyroid, meaning shield, by the Ancient Greeks because it resembles a shield. The gland located in the midline, just below and in front of the larynx, was given the same name due to its proximity to this cartilage. The thyroid gland consists of right and left parts that meet in the middle. In front of this gland, there are muscle groups and neck skin extending from top to bottom. This organ has more vessels than many tissues in the body and releases the hormones it secretes into the blood through these vessels, and these hormones that regulate metabolism are carried to all body tissues by blood. These vitally important hormones regulate metabolism.

How to understand whether the thyroid gland is working or not?

The best information about the functions of the thyroid gland is given by the TSH hormone secreted from the part of the brain called the pituitary. This substance stimulates the hormone-secreting structures in the thyroid gland, allowing more hormones to be produced and released into the blood. When the thyroid gland is underactive, the release of TSH from the pituitary into the blood increases. If the thyroid begins to produce more hormones on its own, the pituitary reduces TSH production and the TSH measurement in the blood shows values ​​below normal limits. In addition to TSH, measurement of free T4 (FT4) and free T3 (FT3) hormones also provides information about the functions of the thyroid in some cases and is requested from the laboratory by your physician.

What happens if the thyroid gland works poorly?

The underactivity of this gland and the inability to secrete the required amount of thyroid hormone for body tissues is called hypothyroidism. In this case, the level of thyroid hormones in the blood decreases and sufficient amounts of hormones do not reach the tissues. Body functions slow down, the patient begins to feel cold more easily, gets tired easily, and symptoms such as weight gain, hair loss, dry skin, constipation, and forgetfulness occur. Hypothyroidism most commonly occurs as a result of thyroid gland inflammation called autoimmune thyroiditis, which occurs when the body's immune system wages war on its own tissues, surgical removal of the thyroid gland for cancer or other reasons, or radioactive iodine (atomic) treatment. This situation is usually It lasts a lifetime and the patient must take thyroid hormone orally in pill form for life and must be under the control of a hormone diseases specialist (endocrinologist).

What happens if the thyroid gland works too much?

Overwork of the thyroid gland and its secretion of hormones above the amount required for the tissues is called hyperthyroidism. Thyroid hormones reaching the tissues in higher than normal amounts cause an increase in all functions in the body. Symptoms include increased heart rate, palpitations, tremors in the hands, clammy skin, irritability, restlessness, and weight loss without loss of appetite. In Basedow-Graves disease, which is one of the most common causes of hyperthyroidism, in addition to these signs and symptoms, the eyes appear excessively large and protrude as a result of the eyelids opening too much.

Apart from Basedow-Graves disease, toxic (poisonous) nodular goiter ( Thyroid containing a single or multiple lumps) and thyroiditis are also among the causes of hyperthyroidism. The treatment of this disorder can be done in 3 ways:
 

• Eliminating the effects of over-secreted thyroid hormones with oral medications.
• Reducing the overactive thyroid tissue with radioactive iodine (atomic) treatment. destruction and a decrease in the amount of secreted hormones.
• Removal of the entire or almost complete part of the thyroid gland by surgery.
• What is goiter? Conditions in which the thyroid gland enlarges is called goiter. This may be due to cancer, or it may be due to insufficient iodine intake in the diet or intake of goiter-inducing foods such as kale. The condition in which the entire thyroid gland grows homogeneously is called diffuse goiter, and the condition in which nodules (lumps) are located within the thyroid gland is called multinodular goiter. As the devices called ultrasound, which create images by very sensitively recording the reflections of sound waves sent to body tissues, have developed, most of the diffuse goiters have been classified as multinodular goiters, with the detection of previously undetected nodules.

Thyroid nodule. why?

Cells in certain areas of the thyroid gland grow and form a mass, different density and hardness compared to other parts of the thyroid. When it forms a lump, it is called a nodule. Nodules may be found singly within the thyroid gland (solitary thyroid nodule) or may be multiple spread throughout the thyroid. (multinodular goiter) In addition, nodules are divided into two according to their content: solid nodule (containing no fluid) and cystic nodule (containing fluid).

In the medical imaging method called Thyroid scintigraphy, which is performed by administering a small amount of radioactive material, nodules are divided into two: cold nodule (non-functioning) and hot nodule (functioning). Most nodules do not cause any symptoms and are only noticed by the patient if they are large enough. Very large nodules create swelling on the patient's neck that can be easily noticed by others. Large nodules can also cause some symptoms by putting pressure on the trachea and esophagus. Nodules that secrete excessive hormones are the cause of hyperthyroidism, the signs and symptoms of which are listed above. In medical examinations performed with a device called ultrasound, millimetric nodules that are impossible for the physician to detect during manual examination can also be seen, but in general, nodules smaller than 10 millimeters do not worry physicians much. The clinical importance of nodules is that they can harbor cancer. Various scientific studies have reported that 5 to 10% of nodules are malignant. This risk increases even more in some cases. For example, in children, men, elderly patients, patients who received radiotherapy (beam or radiation therapy) to the head and neck region in childhood for any reason, patients with hoarseness or a lymph node in the neck along with the nodule, the probability of the nodule being malignant is higher. In addition to manual examination in the evaluation of nodules, measurement of thyroid hormones (T3, T4 and TSH), needle biopsy of the nodule, ultrasound examination of the nodule and the remaining thyroid tissue and its length help us decide on the character of the nodule and the type of treatment. Thyroid scintigraphy, which was more widely used in previous years and was a film taken by injecting radioactive substances into the body, has now become an imaging method used only in certain special cases. With the development of technology, ultrasound, which provides much more detailed images, has largely replaced thyroid scintigraphy. Thyroid nodule� � During the follow-up of the patient, after a good history taken from the patient and a good examination of the patient, the basic examinations that provide the most information to the physicians and are probably the most frequently requested are: TSH and free T4 measurement, imaging of the thyroid and neck with ultrasound, and biopsy of suspicious nodules with a fine needle. can be listed as.

When is thyroid surgery performed?

Surgical removal of one side or the entire thyroid gland is a generally applied treatment method in the following cases:

• The nodule is detected to be cancerous or raises suspicion of cancer,
• The thyroid gland or nodule puts pressure on the esophagus and respiratory pipes and causes symptoms related to swallowing and breathing,
• The thyroid gland or nodule is excessively large and distorts the patient's appearance,
• The thyroid gland or nodule causes symptoms related to swallowing and breathing. overactivity of the nodule, leading to hyperthyroidism

What should be taken into consideration during thyroid surgery?

Since the thyroid gland is located just in front of the larynx and the beginning of the trachea, it is in close proximity to the vocal cord nerve. Damage to these nerves causes voice changes that can lead to severe hoarseness. In addition, on the back surface of the thyroid, there are four glands called parathyroids, two on the right and two on the left, each about the size of a lentil. It regulates the calcium level in the blood with the hormone secreted by these glands. In order for calcium to be kept at a certain level in the blood, it is sufficient for at least two of these glands to be fully functional. However, in surgeries where both sides of the thyroid are removed, all four parathyroids are unintentionally removed or their vessels are damaged and they become anemic, resulting in temporary, but sometimes permanent, decreases in blood calcium levels. A decrease in blood calcium may cause numbness around the patient's hands, feet and lips, as well as contractions and cramps in the arms and legs. While oral or intravenous calcium medications are sufficient for temporary calcium drops, vitamin D should be given to the patient in addition to calcium in case of permanent hormone deficiency and calcium drop. It is very important to protect the important structures described above and not damage them during the surgery. The surgeon's main goal is to remove the thyroid gland n must also protect these vital structures. In the hands of an experienced surgeon who uses the correct surgical technique, the likelihood of the permanent complications mentioned above is very low.

What kind of surgical technique should be applied to the patient? The problem in the thyroid gland (a cancer-suspicious nodule or a nodule that secretes excessive hormones) may sometimes be limited to only one half of the gland. In this case, removing the problematic side of the thyroid will be sufficient. In this case, it is essential to remove the entire gland on the operated side. However, sometimes pathology examinations performed during and sometimes after the surgery may indicate the need to remove the other half of the thyroid. In these patients, the other half of the thyroid gland is completely removed. In some cases, the problem exists on both sides of the thyroid and it may be decided to remove the entire thyroid gland from the beginning. Occasionally, a small piece may be left in place on one side of the gland, often adjacent to the upper feeding vessels. However, if the patient has thyroid cancer, the surgeon must often choose to remove the entire gland.

As a result, contemporary practice in surgery of the thyroid gland is to remove the entire gland on the operated side, with some exceptions. In fact, in bilateral thyroid surgery, an attempt is made to remove the anatomical appendages and extensions of the gland. Some disadvantages may arise for the patient after surgeries that are not performed in this way:

• If the disease on the removed side (for example, nodular goiter) recurs in the future, it will be more difficult to operate on the same side again, and the risk of complications in the second surgery is higher.
• In case the patient has thyroid cancer, examination of the substance called thyroglobulin, secreted by healthy and cancerous thyroid cells after surgery, will reveal possible recurrences at an early stage. If thyroid tissue is left behind, it is not known whether the thyroglobulin detected in the blood is secreted due to a recurrence or whether it is secreted from the thyroid tissue left behind. In this case, this valuable recurrence marker cannot be used for that patient.
• In addition, postoperative radioactive iodine (atomic) treatment may be required in most thyroid cancers. In both cases, leaving thyroid tissue behind will be a serious disadvantage. Thyroid gland is OK

  _{Read: 0}