Endoscopic selective neck dissection in a porcine model

Objective: To investigate the feasibility of accomplishing a selective neck dissection (SND) endoscopically. Study Design: Prospective, nonrandomized experimental investigation in a porcine model. Methods: Unilateral endoscopic SNDs were performed in Yorkshire pigs. A spacious operative pocket was developed using a combination of hernia balloon expansion followed by low-pressure (4 mm Hg) carbon dioxide insufflation. The sternomastoid muscle, thymus, submandibular gland, lymph nodes, and fibrofatty tissue were removed in a procedure approximating a human SND. Data (operative time, blood loss, arterial blood gas values, weight of the specimen, and complications) were prospectively recorded. The specimens were analyzed by a pathologist, and the number and size of lymph nodes were recorded. Results: Fourteen endoscopic SNDs were successfully performed. No conversions to open surgery were necessary. The median operative time was 131 minutes (range, 95-235 minutes). The median estimated blood loss was 4 mL (range, 0-150 mL). The mean ± SD specimen weight was 42.9 ± 8.3 g; the mean number ± SD of nodes retrieved from the neck specimen was 4.8 ± 2.2, and the mean ± SD maximal nodal dimension was 2.4 ± 0.5 cm. The arterial PCO₂ increased by an average of only 3.9 mm Hg from the beginning to the end of the surgery; correspondingly, the pH fell by only 0.02. There were no major complications, and no animals had to be euthanized prior to the completion of the procedure. Conclusions: Endoscopic neck dissection in a porcine model can be accomplished with a combination of strategies to overcome the dilemma of creating and maintaining an operative pocket. The merger of SND with endoscopic technology offers the promise of truly minimally invasive surgery for the node-negative neck.