Intraoperative monitoring of the recurrent laryngeal nerve in surgeries for thyroid cancer: a review

Abstract

Intraoperative nerve monitoring (IONM) has evolved into an objective tool not only for the identification but also for the preservation and prognostication of function of the recurrent laryngeal nerve in thyroid surgeries. Technical improvements have resulted in the increasing incorporation of IONM into operating rooms around the world. The importance of adherence to recommended standards is also recognized as being vital in optimizing the efficacy of IONM. The advent of continuous IONM has made real-time nerve monitoring possible, thus providing the surgeon with an ally in difficult surgeries. Additionally, as thyroid surgeries are evolving into remote access and minimally invasive procedures, so also is the applicability of IONM. This review focuses on the use of IONM for nerve monitoring in thyroidectomies for neoplastic conditions while discussing the rationale, technique, and interpretation of findings and their implications.

Keywords

Intraoperative nerve monitoring / thyroidectomy / recurrent laryngeal nerve / electromyography / vagus nerve

References

[1] Gourin CG,Forastiere AA,Pawlik TM.Volume-based trends in thyroid surgery.Arch Otolaryngol Head Neck Surg2010;136:1191-8

[2] Misiolek M,Namyslowski G,Podwinski A.Recurrent laryngeal nerve palsy after thyroid cancer surgery: a laryngological and surgical problem.Eur Arch Otorhinolaryngol2001;258:460-2

[3] Toniato A,Piotto A.Complications in thyroid surgery for carcinoma: one institution's surgical experience.World J Surg2008;32:572-5

[4] Lefevre JH,Leenhardt L,Chigot JP.Reoperative surgery for thyroid disease.Langenbecks Arch Surg2007;392:685-91

[5] Pantvaidya G,Deshmukh A,D'Cruz A.Does the recurrent laryngeal nerve recover function after initial dysfunction in patients undergoing thyroidectomy?.Laryngoscope Investig Otolaryngol2018;3:249-52 PMCID:PMC6057219

[6] Steurer M,Denk DM,Niederle B.Advantages of recurrent laryngeal nerve identification in thyroidectomy and parathyroidectomy and the importance of preoperative and postoperative laryngoscopic examination in more than 1000 nerves at risk.Laryngoscope2002;112:124-33

[7] Baba M,Shimada M.Does hoarseness of voice from recurrent nerve paralysis after esophagectomy for carcinoma influence patient quality of life?.J Am Coll Surg1999;188:231-6

[8] Nouraei SAR,Kaddour H.Vocal palsy increases the risk of lower respiratory tract infection in low-risk, low-morbidity patients undergoing thyroidectomy for benign disease: a big data analysis.Clin Otolaryngol2017;42:1259-66

[9] Equipment, recording techniques, data analysis, and stimulation. Intraoperative neurophysiological monitoring. Totowa: Humana Press; 2006. p. 299-328.

[10] Irkorucu O,Arslan E.Nerve monitoring in the hands of less experienced surgeons.Indian J Surg2014;76:257-8 PMCID:PMC4141063

[11] Dionigi G,Kim HY,Boni L.Severity of recurrent laryngeal nerve injuries in thyroid surgery.World J Surg2016;40:1373-81

[12] Chiang FY,Kuo WR,Chang NC.The mechanism of recurrent laryngeal nerve injury during thyroid surgery-the application of intraoperative neuromonitoring.Surgery2008;143:743-9

[13] Zheng S,Wei Y,He J.Effect of intraoperative neuromonitoring on recurrent laryngeal nerve palsy rates after thyroid surgery-a meta-analysis.J Formos Med Assoc2013;112:463-72

[14] Schneider R,Randolph GW,Lorenz K.Opportunities and challenges of intermittent and continuous intraoperative neural monitoring in thyroid surgery.Gland Surg2017;6:537-45 PMCID:PMC5676169

[15] Johnson RL,Staff NP.Neuropathies after surgery: anatomical considerations of pathologic mechanisms.Clin Anat2015;28:678-82

[16] Lamadé W,Lauzana E.The weepy nerve-different sensitivity of left and right recurrent laryngeal nerves under tensile stress in a porcine model.Langenbecks Arch Surg2016;401:983-90

[17] Phelan E,Lorenz K.Continuous vagal IONM prevents recurrent laryngeal nerve paralysis by revealing initial EMG changes of impending neuropraxic injury: a prospective, multicenter study.Laryngoscope2014;124:1498-505

[18] Schneider R,Dionigi G.Prospective study of vocal fold function after loss of the neuromonitoring signal in thyroid surgery: The International Neural Monitoring Study Group's POLT study.Laryngoscope2016;126:1260-6

[19] Waller A.Experiments on the section of the glosso-pharyngeal and hypoglossal nerves of the frog, and observations of the alterations produced thereby in the structure of their primitive fibres.Edinb Med Surg J1851;76:369-76 PMCID:PMC5929074

[20] Schneider R,Dionigi G.International neural monitoring study group guideline 2018 part I: staging bilateral thyroid surgery with monitoring loss of signal.Laryngoscope2018;128 Suppl 3:S1-17

[21] Pragacz K.Evaluation of the learning curve for intraoperative neural monitoring of the recurrent laryngeal nerves in thyroid surgery.Pol Przegl Chir2015;86:584-93

[22] Dionigi G,Boni L,Dionigi R.What is the learning curve for intraoperative neuromonitoring in thyroid surgery?.Int J Surg2008;6 Suppl 1:S7-12

[23] Alesina PF,Meier B,Bolli M.Intraoperative neuromonitoring for surgical training in thyroid surgery: its routine use allows a safe operation instead of lack of experienced mentoring.World J Surg2014;38:592-8

[24] Prass RL,Hardy RW Jr,Lüders H.Acoustic (loudspeaker) facial EMG monitoring: II. Use of evoked EMG activity during acoustic neuroma resection.Otolaryngol Head Neck Surg1987;97:541-51

[25] Park JH.Intraoperative neurophysiological monitoring in spinal surgery.World J Clin Cases2015;3:765-73 PMCID:PMC4568525

[26] Thirumala PD,Habeych M.Value of free-run electromyographic monitoring of lower cranial nerves in endoscopic endonasal approach to skull base surgeries.J Neurol Surg B Skull Base2012;73:236-44 PMCID:PMC3424031

[27] Shedd DP.Electrical identification of the recurrent laryngeal nerve. I. Response of the canine larynx to electrical stimulation of the recurrent laryngeal nerve.Ann Surg1966;163:47-50 PMCID:PMC1476845

[28] Dralle H,Angelos P.Intraoperative monitoring of the recurrent laryngeal nerve during thyroidectomy: a standardized approach part 2.World Journal of Endocrine Surgery2012;4:33-40

[29] Julien N,Bozorg Grayeli A,Ferrary E.Intraoperative laryngeal nerve monitoring during thyroidectomy and parathyroidectomy: A prospective study.Eur Ann Otorhinolaryngol Head Neck Dis2012;129:69-76

[30] Lipton RJ,Litchy WJ.Intraoperative electrophysiologic monitoring of laryngeal muscle during thyroid surgery.Laryngoscope1988;98:1292-6

[31] Randolph GW,Abdullah H.International Intraoperative Monitoring Study Group. Electrophysiologic recurrent laryngeal nerve monitoring during thyroid and parathyroid surgery: international standards guideline statement.Laryngoscope2011;121 Suppl 1:S1-16

[32] NIM® 3.0 Systems: protocol and trouble Shooting guide - a comprehensive guide to nerve integrity monitoring, Medtronic Inc. Jacksonville: Johnson & Johnson; 2012. p.17.

[33] Randolph GW.Intraoperative neural monitoring in thyroid cancer surgery.Langenbecks Arch Surg2014;399:199-207

[34] Kim J.We Asked the Experts: How can one troubleshoot loss of intraoperative nerve monitoring during head and neck surgery?.World J Surg2020;44:1874-5

[35] Gurleyik E.Nonrecurrent laryngeal nerve in the era of intraoperative nerve monitoring.Adv Med2016;2016:1606029 PMCID:PMC5081457

[36] Pearlman RC,Ruben GD.Intraoperative monitoring of the recurrent laryngeal nerve using acoustic, free-run, and evoked electromyography.J Clin Neurophysiol2005;22:148-52

[37] Satoh I.Evoked electromyographic test applied for recurrent laryngeal nerve paralysis.Laryngoscope1978;88:2022-31

[38] Potenza AS,Cernea CR.Normative intra-operative electrophysiologic waveform analysis of superior laryngeal nerve external branch and recurrent laryngeal nerve in patients undergoing thyroid surgery.World J Surg2013;37:2336-42

[39] Caragacianu D,Randolph GW.Intraoperative monitoring: normative range associated with normal postoperative glottic function.Laryngoscope2013;123:3026-31

[40] Sritharan N,Kamani D,Randolph GW.The vagus nerve, recurrent laryngeal nerve, and external branch of the superior laryngeal nerve have unique latencies allowing for intraoperative documentation of intact neural function during thyroid surgery.Laryngoscope2015;125:E84-9

[41] Schneider R,Lorenz K.Intraoperative nerve monitoring in thyroid surgery-shifting current paradigms.Gland Surg2020;9:S120-8 PMCID:PMC7044089

[42] Brauckhoff K,Sandvik L.Impact of EMG changes in continuous vagal nerve monitoring in high-risk endocrine neck surgery.World J Surg2016;40:672-80 PMCID:PMC4746223

[43] Wu CW,Chen CC.Loss of signal in recurrent nerve neuromonitoring: causes and management.Gland Surg2015;4:19-26 PMCID:PMC4321049

[44] Miyauchi A,Matsusaka K,Matsuzuka F,Kuma K.[Treatment of recurrent laryngeal nerve paralysis by several types of nerve suture].Nihon Geka Gakkai Zasshi1993;94:550-5. (in Japanese)

[45] Wang LF,Kuo WR,Lu SP.The efficacy of intraoperative corticosteroids in recurrent laryngeal nerve palsy after thyroid surgery.World J Surg2006;30:299-303

[46] Schneider R,Machens A,Nguyen Thanh P.Postoperative vocal fold palsy in patients undergoing thyroid surgery with continuous or intermittent nerve monitoring.Br J Surg2015;102:1380-7

[47] Barczyński M,Cichoń S.Randomized clinical trial of visualization versus neuromonitoring of recurrent laryngeal nerves during thyroidectomy.Br J Surg2009;96:240-6

[48] Cavicchi O,Fernandez IJ.The value of neurostimulation and intraoperative nerve monitoring of inferior laryngeal nerve in thyroid surgery.Otolaryngol Head Neck Surg2009;140:866-70

[49] Maneeprasopchoke P,Pongsapich W,Kamani D.Intraoperative nerve monitoring in thyroid surgery: analysis of recurrent laryngeal nerve identification and operative time.Laryngoscope Investig Otolaryngol2021;6:354-61 PMCID:PMC8035947

[50] Salari B,Kamani D.Staged surgery for advanced thyroid cancers: safety and oncologic outcomes of neural monitored surgery.Otolaryngol Head Neck Surg2017;156:816-21

[51] Goretzki PE,Brinkmann J,Lammers BJ.The impact of intraoperative neuromonitoring (IONM) on surgical strategy in bilateral thyroid diseases: is it worth the effort?.World J Surg2010;34:1274-84

[52] Melin M,Pearson MD,Goretzki PE.Postoperative vocal cord dysfunction despite normal intraoperative neuromonitoring: an unexpected complication with the risk of bilateral palsy.World J Surg2014;38:2597-602

[53] Terris DJ,Carneiro-Pla D.American thyroid association surgical affairs committee writing task force. American thyroid association statement on outpatient thyroidectomy.Thyroid2013;23:1193-202

[54] Schneider R,Sekulla C,Weber F.Twenty-year experience of paediatric thyroid surgery using intraoperative nerve monitoring.Br J Surg2018;105:996-1005

[55] Hermann M,Freissmuth M.Neuromonitoring in thyroid surgery: prospective evaluation of intraoperative electrophysiological responses for the prediction of recurrent laryngeal nerve injury.Ann Surg2004;240:9-17 PMCID:PMC1356368

[56] Kamani D,Cernea CR,Randolph GW.The nonrecurrent laryngeal nerve: anatomic and electrophysiologic algorithm for reliable identification.Laryngoscope2015;125:503-8

[57] Dionigi G,Boni L.Continuous monitoring of the recurrent laryngeal nerve in thyroid surgery: a critical appraisal.International Journal of Surgery2013;11:S44-6

[58] Çekiç E,Sürmelioğlu Ö,Hatipoğlu E.Effect of intraoperative neuromonitoring on voice quality in total thyroidectomy.Haseki2018;56:118-24

[59] Lamadé W,Seimer A.A new system for continuous recurrent laryngeal nerve monitoring.Minim Invasive Ther Allied Technol2007;16:149-54

[60] Barczyński M,Cernea CR.International neural monitoring study group. External branch of the superior laryngeal nerve monitoring during thyroid and parathyroid surgery: international neural monitoring study group standards guideline statement.Laryngoscope2013;123 Suppl 4:S1-14

[61] Sun H.Monitoring the external branch of the superior laryngeal nerve in thyroid surgery.Ann Thyroid2018;3:9-9

[62] Uludag M,Kartal K.Contribution of intraoperative neural monitoring to preservation of the external branch of the superior laryngeal nerve: a randomized prospective clinical trial.Langenbecks Arch Surg2017;402:965-76

[63] Glover AR,Gundara JS,Sidhu SB.Use of the nerve integrity monitor during thyroid surgery aids identification of the external branch of the superior laryngeal nerve.Ann Surg Oncol2015;22:1768-73

[64] Lang BH.Feasibility on the use of intraoperative vagal nerve stimulation in gasless, transaxillary endoscopic, and robotic-assisted thyroidectomy.J Laparoendosc Adv Surg Tech A2011;21:911-7

[65] Kandil E,Aslam R,Bellows C.Transaxillary gasless robotic thyroid surgery with nerve monitoring: initial two experince in a North American center.Minim Invasive Ther Allied Technol2012;21:90-5

[66] Zhao Y,Zhang D.Continuous neural monitoring in endoscopic thyroidectomy: feasibility experimental study for transcutaneous vagal nerve stimulation.J Laparoendosc Adv Surg Tech A2020;30:1095-101

[67] Calò PG,Medas F.Identification alone versus intraoperative neuromonitoring of the recurrent laryngeal nerve during thyroid surgery: experience of 2034 consecutive patients.J Otolaryngol Head Neck Surg2014;43:16 PMCID:PMC4074847

[68] Calò PG,Erdas E.Role of intraoperative neuromonitoring of recurrent laryngeal nerves in the outcomes of surgery for thyroid cancer.Int J Surg2014;12 Suppl 1:S213-7