Why is a lobe removed and not the entire organ?
When the pathological process is limited to one lobe, there is no point in removing the entire gland. Hemithyroidectomy preserves the contralateral lobe and in most cases is sufficient to maintain normal hormone levels without lifelong replacement therapy. In addition, with unilateral intervention, the risk of damage to the recurrent laryngeal nerve and parathyroid glands is half as much as when the entire gland is removed.
The main indications are a nodular goiter of one lobe with signs of compression of the trachea or esophagus, a cosmetic defect, a follicular tumor of uncertain malignant potential based on puncture results (Bethesda categories III and IV), an autonomously functioning node, as well as small differentiated low-risk thyroid cancer, where such a volume is considered sufficient by modern recommendations.
The operation is performed through a 4-6 centimeter incision in the natural crease of the neck under general anesthesia and takes about an hour. The removed lobe is necessarily sent for histological examination, the result of which is ready in 7–10 days and is the final diagnosis. If histology reveals cancer with unfavorable features, a second stage may require removal of the remaining lobe. After 4–6 weeks, the TSH level is checked: in approximately some patients, the remaining portion does not fully compensate for the function, and a dose of levothyroxine is selected for them.
Thyroid nodules: what is important to know
Thyroid nodules are very common and in the vast majority of cases are benign. The doctor’s task is to identify those few that require intervention, and not subject the rest to unnecessary procedures.
The selection is carried out according to ultrasound characteristics: shape, contours, echogenicity, the presence of microcalcifications and the nature of blood flow. Based on their totality, the node is assigned a TI-RADS category, which, together with its size, determines the indications for puncture.
The role of the recurrent laryngeal nerve
The recurrent laryngeal nerve runs directly along the posterior surface of the thyroid gland and controls the vocal cords. Its damage leads to hoarseness, and if bilateral, to respiratory failure.
That is why thyroid surgery is performed by a specialized surgeon, and the mobility of the vocal cords is assessed before and after the intervention. Modern techniques include visual identification of the nerve, and in some cases, intraoperative neuromonitoring.
Hormonal control after intervention
Removing part of the gland can lead to decreased hormone production. Therefore, 4–6 weeks after surgery, the TSH level is determined and, if necessary, the dose of levothyroxine is adjusted.
Blood calcium is separately controlled: next to the thyroid gland there are parathyroid glands that regulate calcium metabolism. Their temporary dysfunction after surgery is possible and is manifested by numbness and tingling in the fingers and around the mouth.