Endoscopic or minimally invasive surgery (MIS – Minimally Invasive Surgery) is becoming increasingly popular. Since the first endoscopic cholecystectomy was performed in the early 1980s, endoscopic techniques have been prevalent in almost all areas of surgery. In view of the extremely rapid advance in technical means, the evolution of these innovative processes seems to be unstoppable.
In thyroid surgery, these applications were started later. It is much more difficult to find endoscopic access to the thyroid gland, Mainly because of its location in the human body. All space required for the manipulations must be created because there is no physical cavity.
Endoscopic thyroidectomy has been practiced since the late 1990s. Minimally invasive cervical surgeries can be classified into a direct/cervical approach and an indirect / extra-cervical approach. Immediate access involves a small incision in the neck, while gland resection is performed in a conventional manner, though using endoscopic instruments. Extracellular access includes axillary, posterior, and nipple access. The development of extra-cervical thyroid surgery is a big step towards a better aesthetic outcome. However, these techniques have essentially moved the incisions from the cervical region to the armpit or chest where they are still visible. In addition, they do not fully meet the term “minimally invasive” because they are associated with extensive preparations in the thoracic and throat area, so they are probably much more invasive to patients. So while endoscopic thyroidectomy may not be an innovative technique, transverse endoscopic thyroidectomy is a recent development, really free of skin incisions and scars.
The main goal of the innovation was to introduce a technical thyroid resection that fulfills the following criteria: a) Respect for surgical anatomy and minimize surgical trauma b) Access should be close to the thyroid gland in order to achieve a minimum invasive procedure c) Achieving an optimal aesthetic effect can only be achieved by performing an operation without obvious incision d) The desired aesthetic result should be achieved with the least possible trauma e) The minimally invasive nature of this approach and the optimal aesthetic effect cannot be achieved to the detriment of patient safety.
The technique that meets all the above criteria is cross-sectional, because the distance to the thyroid gland is small, thus avoiding extensive preparations. In addition, the mucosa of the mouth can be easily stitched and has the ability to heal without leaving visible scars.
Patient selection criteria are specific and internationally include small gland diameter, thyroid volume ≤ 45mL, nodule size ≤ 50mm, benign nodule, and selected cases of malignancy have been added in recent years. TOETVA (TransOral Endoscopic Thyroidectomy Vestibular Approach) is performed using a three-trocar technique placed on the lower lip of the mouth. The CO2 supply pressure is low. The anterior cervical space is made from the lower lip to the sternum, and laterally to the sternocleidomastoid muscles. Thyroidectomy is performed completely endoscopically using conventional endoscopic instruments. Postoperative neurodegeneration is used to identify both the upper and lower laryngeal nerves. The preparation is extracted from the central incision in an endoscopic bag. The patient is discharged the next day with instructions for reassessment as in conventional open thyroidectomy. Although technically more difficult, the expected intraoperative and postoperative complications do not differ from those of conventional thyroidectomy as basic anatomical structures such as vessels, nerves, parathyroid glands, are more easily recognized due to the enlarged endoscopic field.
In conclusion, oral endoscopic thyroidectomy is a safe innovative method with specific indications. A basic condition is that it can be performed exclusively by a specialized and highly trained surgeon. It is becoming more and more widely accepted worldwide, not only for its equal results compared to open thyroidectomy, but also for its unique aesthetic effect. It is still the only method of thyroidectomy without incision in the skin and without obvious scarring.