Che-Wei Wu1,2, Young Jun Chai3, Gianlorenzo Dionigi4, Feng-Yu Chiang1,2, Xiaoli Liu5, Hui Sun5, Gregory W Randolph6,7, Ralph P Tufano8, Hoon Yub Kim9. 1. Department of Otorhinolaryngology-Head and Neck Surgery, Kaohsiung Medical University Hospital, Kaohsiung Medical University. 2. Faculty of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan. 3. Department of Surgery, Seoul National University Boramae Medical Center, Seoul, Korea. 4. Endocrine Surgery Research Center, Department of Surgical Sciences, University of Insubria, Varese-Como, Varese, Italy. 5. Department of Thyroid and Parathyroid Surgery, China-Japan Union Hospital, Jilin University & Jilin Provincial Key Laboratory of Surgical Translational Medicine, Changchun, Jilin, China. 6. Division of Thyroid and Parathyroid Surgery, Department of Laryngology and Otology, Massachusetts Eye and Ear Infirmary, Harvard Medical School. 7. Division of Surgical Oncology, Department of Surgery, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts, U.S.A. 8. Division of Head and Neck Endocrine Surgery, Department of Otolaryngology-Head and Neck Surgery, Johns Hopkins School of Medicine, Baltimore, Maryland, U.S.A. 9. Department of Surgery, KUMC Thyroid Center, Korea University Hospital, Korea University College of Medicine, Seoul, Korea.
Abstract
OBJECTIVES/HYPOTHESIS: The Harmonic Focus (HF) is one of the most popular energy-based devices. The aim of this study was to provide recurrent laryngeal nerve (RLN) functional data that define the safety parameters of the HF during thyroidectomy. STUDY DESIGN: Prospective porcine model using continuous electrophysiologic monitoring. METHODS: Ten piglets were used. At varying distances from the RLN, the HF was activated (activation study). The HF was also applied directly on the RLN after activation on sternocleidomastoid muscle for 10 seconds with different cooling times (cooling study). RESULTS: In the activation study, there was no adverse electromyography (EMG) event at more than 1 mm distance. In the cooling study, there was no adverse EMG event after a 10-second cooling period. When the HF was cooled on the sternocleidomastoid muscle, there was no adverse EMG event after 2 seconds cooling time. CONCLUSIONS: The safe distance of the HF was 1 mm, and it should be cooled for more than 10 seconds or 2 seconds after cooling on muscle. The HF should be used in a standardized manner to avoid RLN injury. LEVEL OF EVIDENCE: NA.
OBJECTIVES/HYPOTHESIS: The Harmonic Focus (HF) is one of the most popular energy-based devices. The aim of this study was to provide recurrent laryngeal nerve (RLN) functional data that define the safety parameters of the HF during thyroidectomy. STUDY DESIGN: Prospective porcine model using continuous electrophysiologic monitoring. METHODS: Ten piglets were used. At varying distances from the RLN, the HF was activated (activation study). The HF was also applied directly on the RLN after activation on sternocleidomastoid muscle for 10 seconds with different cooling times (cooling study). RESULTS: In the activation study, there was no adverse electromyography (EMG) event at more than 1 mm distance. In the cooling study, there was no adverse EMG event after a 10-second cooling period. When the HF was cooled on the sternocleidomastoid muscle, there was no adverse EMG event after 2 seconds cooling time. CONCLUSIONS: The safe distance of the HF was 1 mm, and it should be cooled for more than 10 seconds or 2 seconds after cooling on muscle. The HF should be used in a standardized manner to avoid RLN injury. LEVEL OF EVIDENCE: NA.
Authors: Sam Van Slycke; Jean-Pierre Gillardin; Klaas Van Den Heede; Joan Minguet; Hubert Vermeersch; Nele Brusselaers Journal: Langenbecks Arch Surg Date: 2016-05-25 Impact factor: 3.445