Thyroid surgery with a harmonic scalpel: an experimental study

Abstract

BackgroundThe goal of the study was to determinate the safety of the harmonic scalpel, widely used in thyroidectomy, near the recurrent laryngeal nerve (RLN).MethodsThe study involved ten pigs of either sex. Twenty RLNs at risk were dissected using the new harmonic scalpel FOCUS. The distances between the nerve and the activated instrument were checked with a millimeter ruler. After dissection, the pigs were euthanized, and both RLNs were fixed in formol and examined by histology after staining with hematoxylin–eosin. Due to technical reasons, only 18 RLNs from the ten pigs could be examined.ResultsIn the experiment that investigated the extent of heat injury, ultrasonic dissection did not cause any immediate damage of the nerve even close to the RLN (1 mm away from the RLN).ConclusionThe use of harmonic scalpel FOCUS for thyroid surgery is safe for the surrounding structures (nerves). Careful tissue applications of the device near the RLN (1 mm) did not cause any lesion histologically.

Safety of energy based devices for hemostasis in thyroid surgery

“…In the activation study, there was no adverse electromyography (EMG) event at more than 1 mm distance (Figure 1). In the cooling study, there was no adverse EMG event after a 10-second cooling period (22,24). When the HF was cooled on the sternocleidomastoid muscle, there was no adverse EMG event after 2 seconds cooling time.…”

“…On the contrary, a potential drawback is, for some authors, the increased health care costs (10)(11)(12)(13)(14)(15)(16). In addition, EBD are essential for endoscopic procedures (16)(17)(18)(19)(20)(21)(22).…”

“…Different surveys describe the safety of EBD around the RLN (22)(23)(24)(25)(26)(27). Such investigations are needful as they highlighted areas for correction in the adoption of the technology in thyroid and parathyroid surgery (19).…”

“…Recent studies were to provide RLN functional data that define the safety parameters of the HF during thyroidectomy (22,24). Most these studies were prospective porcine model using continuous electrophysiologic monitoring.…”

“…Most these studies were prospective porcine model using continuous electrophysiologic monitoring. Piglets were used (22,24). At varying distances from the RLN, the HF was activated (activation study).…”