Continuous intraoperative neural monitoring of the recurrent nerves in thyroid surgery: a quantum leap in technology.
The continuous intraoperative neural monitoring (CIONM) technique is increasingly acknowledged as a useful tool to recognize impending nerve injury and to abort the related manoeuvre to prevent nerve injury during thyroid surgery. CIONM provides valuable real-time information constantly, which is really useful during complex thyroid surgeries especially in the settings of unusual anatomy. Thus, CIONM overcomes the key methodological limitation inherent in intermittent nerve monitoring (IINOM); which is allowing the nerve to be at risk in between the stimulations. The clinically important combined electromyographic (EMG) event, indicative of impending recurrent laryngeal nerve (RLN) injury, prevents the majority of traction related injuries to the anatomically intact RLN enabling modification of the causative surgical manoeuvre in 80% of cases. These EMG changes can progress to loss of EMG signal with postoperative vocal cord palsy (VCP) if corrective action is not taken. As a further extension, CIONM also helps to identify intraoperative functional nerve recovery with restitution of amplitude to ≥50% of initial baseline; this allows continuing of resection of contralateral side. CIONM facilitates for early corrective action before permanent damage to the nerve has been done. CIONM is a recent but rapidly evolving technique, constantly being refined by various studies focusing on improvement in its implementation and interpretation, as well as on the elimination of the technical snags.
Medical Faculty, Department of General, Visceral, and Vascular Surgery, Martin Luther University Halle-Wittenberg, Halle (Saale), Germany.
Rick
R
Schneider
Division of Thyroid and Parathyroid Surgery Harvard Medical School, Boston, Massachusetts, USA.
Gregory W
GW
Randolph
Department of Endocrine Surgery, 3 Chair of General Surgery, Jagiellonian University, Krakow, Poland.
Marcin
M
Barczynski
Department for Endocrine Surgery, University of Insubria, Varese, Italy.
Gianlorenzo
G
Dionigi
Department of Otolaryngology-Head and Neck Surgery, Kaohsiung Medical University, Kaohsiung City, Taiwan.
Che-Wei
CW
Wu
Department of Otolaryngology-Head and Neck Surgery, Kaohsiung Medical University, Kaohsiung City, Taiwan.
Feng-Yu
FY
Chiang
Medical Faculty, Department of General, Visceral, and Vascular Surgery, Martin Luther University Halle-Wittenberg, Halle (Saale), Germany.
Andreas
A
Machens
Division of Thyroid and Parathyroid Surgery Harvard Medical School, Boston, Massachusetts, USA.
Dipti
D
Kamani
Medical Faculty, Department of General, Visceral, and Vascular Surgery, Martin Luther University Halle-Wittenberg, Halle (Saale), Germany;; Department of General, Visceral and Transplantation Surgery, Section of Endocrine Surgery, University of Duisburg-Essen, Essen, Germany.
Henning
H
Dralle
Intraoperative neuromonitoring; continuous neuromonitoring; laryngeal nerve palsy; thyroidectomy; vagus nerve stimulation