Transoral endoscopic neck surgery: feasibility and safety in a porcine model based on the example of thymectomy

In anatomical studies and cadaver dissections, we developed an endoscopic transoral access to the anterior neck region to reduce surgical access trauma. Through a sublingual trocar and two additional trocars in the vestibule of the oral cavity, the pretracheal and thyroid region was reached with standard laparoscopic instruments.

We conducted an experimental trial in five pigs under general anesthesia to estimate the safety and feasibility of the method; via this approach, the thymus was partially resected. Perioperative antibiotics were administered but analgesics were not given in the postoperative course. Oral intake and behavior were observed during the following 2 days. After necropsy, examination of the access route took place by means of dissections. The tissue surrounding the working trocar was histologically examined.

The pretracheal region could be reached without a problem and the procedure was performed almost "bloodlessly" in an anatomically defined layer. The intervention time decreased successively. Postoperative awakening was uneventful. Regular oral food intake was observed after 2-3 h. Pain reactions were not registered during the entire postoperative phase. After dissection, all relations appeared inconspicuous (no infections, fresh/old hematoma). Two local encapsulated seromas were observed. Histologically, only a mild tissue reaction was noted.

In this study, the endoscopic transoral approach to minimally invasive neck surgery seemed safe and feasible. Minimally invasive endoscopic procedures in the anterior neck region could be a possible application of this new approach.