Transoral access for endoscopic thyroid resection

BACKGROUND: Endoscopic neck surgery is requested by an increasing number of patients. The access trauma of the axillary, breast, and chest approaches is greater than with open or video-assisted surgery. The authors tested the feasibility of the sublingual transoral access, which they believe is the most promising minimally invasive endoscopic access to the thyroid gland from outside the neck region. METHODS: The sublingual transoral access was first evaluated in two fresh human cadavers. An experimental investigation then was performed using a porcine model. A total of 10 endoscopic transoral thyroidectomies were performed in 10 pigs using a modified axilloscope with an obturator, ultrasonic scissors, and a neuromonitoring system to identify the recurrent laryngeal nerve. RESULTS: A complete transoral thyroid resection was achieved with both the human cadavers and all the living pigs. Despite the complexity of the anatomic region, the transoral procedure was astonishingly easy to perform. In the animal study, the time from the introduction of the obturator just above the larynx to its removal was 59 s. The average overall operation time was 50 min. The neuromonitoring system permitted the regular function of the recurrent laryngeal nerves on both sides to be proved after removal of the thyroid gland. The pigs were observed for another 2 h after the operation. No complications occurred during the operation or afterward. CONCLUSIONS: Endoscopic transoral thyroid resection is possible. It proved to be a safe procedure in living pigs and astonishingly easy to perform. The results may be helpful for thyroid resections in humans using a similar access, as suggested by the thyroidectomies in human cadavers preceding this study.