Videoendoscopic thyroidectomy: experimental development of a new technique.

Applications of minimally invasive surgery have evolved from laparoscopic cholecystectomy and spread beyond conventional body cavities to new applications and disease processes. The purpose of the present study was to evaluate the feasibility of performing videoendoscopic thyroidectomy in a canine model. Adult mongrel dogs served as the experimental model for this study. The pretracheal space was entered via a 2.5-cm midline neck incision superior to the sternal notch and then expanded with a balloon spacemaker. A mechanical lift device was used to maintain exposure, and a 12-mm midline cervical port and two lateral 5-mm cervical ports were placed. Dissection was carried out with pediatric endoscopic instruments, and hemostasis was obtained with endoscopic clips and an ultrasonic coagulator. Histologic analysis of the excised tissue was performed in all cases. Mean operative time for thyroid lobectomy was 69 minutes (range 58 to 99). The laryngeal nerves and external parathyroid glands were identified endoscopically in all cases. Blood loss was minimal. No complications were observed intraoperatively or during 1 week of postoperative follow-up. Serum calcium levels were stable. No wound hematomas, laryngeal nerve injuries, or other complications occurred. On average 16 mL (range 2 to 65) of seroma fluid was present in the pretracheal space at autopsy. In conclusion, a videoendoscopic approach to thyroid lobectomy is feasible in an animal model and provides adequate visualization of the important anatomy relevant to this procedure. These techniques may be applicable to thyroidectomy in humans and may impact on minimally invasive surgery in other nontraditional locations.