Thyroid belongs to thyroid surgery or endocrinology. Therefore, once the patient has thyroid-related diseases, it is suggested that the patient should go to these two departments of the hospital for treatment in time, and then undergo regular treatment.

First, the thyroid gland is a very important gland in vertebrates and belongs to endocrine organs. In mammals, it is located under the thyroid cartilage of the neck and on both sides of the trachea. The thyroid gland of human body is shaped like a butterfly and a shield, hence its name.

Second, the thyroid gland controls the speed of energy use, produces protein, and regulates the body's sensitivity to other hormones. The thyroid regulates these reactions by producing thyroxine, including triiodothyronine, also known as tetraiodothyronine. They all regulate metabolism, growth rate and other body systems. T3 and T4 are synthesized from iodine and tyramine acid. The thyroid gland also produces calcitonin, which regulates the balance of calcium in the body.

Third, the thyroid gland is the largest endocrine gland in adults, located in the front of the neck, brownish red, H-shaped, weighing about 25 g; It consists of left and right lobes, isthmus and conical lobes. The left and right lobes of the thyroid gland are conical (the right lobe is slightly larger) and stick to one side of the larynx and trachea. The upper end reaches the middle of thyroid cartilage and the lower end reaches the fourth tracheal ring, which is about 5cm long and 2.4cm wide. Its inner surface is attached to cricoid cartilage through lateral ligament. Therefore, when swallowing, the thyroid gland can move up and down with the larynx.

Fourthly, the thyroid isthmus connects the left and right lobes and is located in front of the 2-4 tracheal cartilaginous rings. A few people can live without thyroid isthmus. More than 60% people have conical leaves protruding upward from the isthmus. Conical leaves vary in length, and some of them can reach the hyoid bone, which is the residue of thyroid development. Near the left and right lobes of the thyroid gland, there is an independent thyroid tissue block called parathyroid gland. The thyroid gland has two capsules, the outer layer is thyroid capsule, which consists of deep cervical fascia (anterior tracheal fascia) and is closely connected with the vascular sheath of the neck. The inner layer, called fibrous capsule, is the capsule of the gland itself, which directly adheres to the surface of the gland tissue and goes deep into the essence of the gland, dividing the gland tissue into several lobules.

5. The connection between thyroid capsule and fibrous capsule is loose and easy to separate, which can be used for intracapsular thyroidectomy in clinic. From the hyoid bone to the isthmus or conical lobe of the thyroid gland, sometimes a small muscle bundle, called levator thyroideus, appears, which has the function of lifting the thyroid gland.

Six, the thyroid parenchyma is mainly composed of many thyroid follicles. Follicular epithelial cells have the function of synthesizing, storing and secreting thyroid hormone. The main function of thyroid hormone is to promote the metabolism of the body and maintain the normal growth and development of the body, which has a great influence on the development of bones and nervous system.

Seven, when the thyroid gland secretion function is low, the body's basal metabolic rate is low, and mucinous edema may occur. If the thyroid secretion function is lost in the fetus or infant period, the development of bones and brains will stagnate, showing short stature and mental retardation. At the onset of hyperthyroidism, there may be rapid heartbeat, insomnia, impatience, hand tremor, etc., which is related to the increased excitability of sympathetic nerve and central nervous system.