Skip to main content
SpringerLink
Log in

Prospective validation study of Cernea classification for predicting EMG alterations of the external branch of the superior laryngeal nerve

  • Original Article
  • Published:
Surgery Today Aims and scope Submit manuscript

Abstract

Purposes

Cernea classification is applied to describe the external branch of the superior laryngeal nerve (EBSLN). Using intraoperative neural monitoring we evaluated whether or not this classification is useful for predicting which EBSLN subtype has an increased risk of injury.

Methods

An analysis of 400 EBSLN. The identification of EBSLN was achieved with both cricothyroid muscle twitch and the glottis evoked electromyography response. We defined S1 initial EBSLN stimulation at identification and S2 final nerve stimulation achieved in the most cranial aspect of the nerve exposed above the area of surgical dissection after superior artery ligation.

Results

The mean S1 amplitude acquired was 259+/67 (180–421), 321 +/79 (192–391), 371 +/38 (200–551) μV, respectively, for type 1, 2A, 2B (p = 0.08). The S1 and S2 amplitudes were similar in type 1 (p = 0.3). The S1 and S2 determinations changed significantly in type 2A and 2B (p = 0.04 and 0.03). EBSLN which demonstrated a >25 % decreased amplitude in S2 increased significantly from Type 1 (4.9 %) to Type 2A (11.2 %) and 2B (18 %) (p = 0.01). None of type 1, 2.8 % type 2A and 3 % type 2B showed a loss of EBSLN conductivity. The latency determinations did not vary significantly for any parameter compared.

Conclusions

The Cernea classification was, therefore, found to predict the risk of EBSLN stress. We identified amplitude differences between S1 and S2 determinations in type 2A and 2B, thus confirming that surgical dissection in these subtypes is, therefore, extremely difficult to perform.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Log in via an institution

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Institutional subscriptions

Fig. 1
Fig. 2

Similar content being viewed by others

References

  1. Kambic V, Zargi M, Radsel Z. Topographic anatomy of the external branch of the superior laryngeal nerve. Its importance in head and neck surgery. J Laryngol Otol. 1984;98:1121–4.

    Article  CAS  PubMed  Google Scholar 

  2. Monfared A, Gorti G, Kim D. Microsurgical anatomy of the laryngeal nerves as related to thyroid surgery. Laryngoscope. 2002;112:386–92.

    Article  PubMed  Google Scholar 

  3. Barczynski M, et al. External branch of the superior laryngeal nerve monitoring during thyroid and parathyroid surgery: international neural monitoring study group standards guideline statement. Laryngoscope. 2013;123(Suppl 4):S1–14.

    Article  PubMed  Google Scholar 

  4. Mangano A, Dionigi G. The need for standardized technique in intraoperative monitoring of the external branch of the superior laryngeal nerve during thyroidectomy. Surgery. 2011;149:854–5.

    Article  PubMed  Google Scholar 

  5. Cernea CR, et al. Surgical anatomy of the external branch of the superior laryngeal nerve. Head Neck. 1992;14:380–3.

    Article  CAS  PubMed  Google Scholar 

  6. Whitfield P, Morton RP, Al-Ali S. Surgical anatomy of the external branch of the superior laryngeal nerve. ANZ J Surg. 2010;80:813–6.

    Article  PubMed  Google Scholar 

  7. Kim S-H, Park HS, Kim K-H, Yoo H, Chae B-J, Bae J-S, Jung S-S, Song B-J. Correlation between obesity and clinicopathological factors in patients with papillary thyroid cancer. Surg Today. 2015;45(6):723–9.

    Article  CAS  PubMed  Google Scholar 

  8. Yalcin Bnt, Develi S, Tubbs RS, Poyrazoglu Y, Yazar F. Blood supply of the terminal part of the external branch of the superior laryngeal nerve. Surg Today. 2014;. doi:10.1007/s00595-014-1051-9.

    PubMed  Google Scholar 

  9. Kierner AC, Aigner M, Burian M. The external branch of the superior laryngeal nerve: its topographical anatomy as related to surgery of the neck. Arch Otolaryngol Head Neck Surg. 1998;124:301–3.

    Article  CAS  PubMed  Google Scholar 

  10. Friedman M, LoSavio P, Ibrahim H. Superior laryngeal nerve identification and preservation in thyroidectomy. Arch Otolaryngol Head Neck Surg. 2002;128:296–303.

    Article  PubMed  Google Scholar 

  11. Selvan B, et al. Mapping the compound muscle action potentials of cricothyroid muscle using electromyography in thyroid operations: a novel method to clinically type the external branch of the superior laryngeal nerve. Ann Surg. 2009;250:293–300.

    Article  PubMed  Google Scholar 

  12. Gimm O, et al. An update on thyroid surgery. Eur J Nucl Med Mol Imaging. 2002;29(Suppl 2):S447–52.

    Article  PubMed  Google Scholar 

  13. Berti P, et al. Visualization of the external branch of the superior laryngeal nerve during video-assisted thyroidectomy. J Am Coll Surg. 2002;195:573–4.

    Article  PubMed  Google Scholar 

  14. Jonas J, Bahr R. Neuromonitoring of the external branch of the superior laryngeal nerve during thyroid surgery. Am J Surg. 2000;179:234–6.

    Article  CAS  PubMed  Google Scholar 

  15. Hurtado-Lopez LM, et al. Importance of the intraoperative identification of the external branch of the superior laryngeal nerve during thyroidectomy: electromyographic evaluation. Thyroid. 2005;15:449–54.

    Article  PubMed  Google Scholar 

  16. Dionigi G, et al. Neuromonitoring and video-assisted thyroidectomy: a prospective, randomized case-control evaluation. Surg Endosc. 2009;23:996–1003.

    Article  PubMed  Google Scholar 

  17. Masuoka H et al. A prospective randomized study on injury of the external branch of the superior laryngeal nerve during thyroidectomy comparing intraoperative nerve monitoring and a conventional technique. Head Neck 2014.

  18. Darr EA, et al. Superior laryngeal nerve quantitative intraoperative monitoring is possible in all thyroid surgeries. Laryngoscope. 2014;124:1035–41.

    Article  PubMed  Google Scholar 

  19. Moosman DA, DeWeese MS. The external laryngeal nerve as related to thyroidectomy. Surg Gynecol Obstet. 1968;127:1011–6.

    CAS  PubMed  Google Scholar 

  20. Potenza AS, et al. Normative intra-operative electrophysiologic waveform analysis of superior laryngeal nerve external branch and recurrent laryngeal nerve in patients undergoing thyroid surgery. World J Surg. 2013;37:2336–42.

    Article  PubMed  Google Scholar 

  21. Randolph GW, et al. Electrophysiologic recurrent laryngeal nerve monitoring during thyroid and parathyroid surgery: international standards guideline statement. Laryngoscope. 2011;121(Suppl 1):S1–16.

    Article  PubMed  Google Scholar 

  22. Schneider R, Randolph GW, Sekulla C, Phelan E, Thanh PN, Bucher M, Machens A, Dralle H, Lorenz K. Continuous intraoperative vagus nerve stimulation for identification of imminent recurrent laryngeal nerve injury. Head Neck. 2013;35(11):1591–8.

    Article  PubMed  Google Scholar 

  23. Brauckhoff M, Walls G, Brauckhoff K, Thanh PN, Thomusch O, Dralle H. Identification of the non-recurrent inferior laryngeal nerve using intraoperative neurostimulation. Langenbecks Arch Surg. 2002;386(7):482–7.

    Article  PubMed  Google Scholar 

  24. Jansson S, et al. Partial superior laryngeal nerve (SLN) lesions before and after thyroid surgery. World J Surg. 1988;12:522–7.

    Article  CAS  PubMed  Google Scholar 

  25. Kark AE, et al. Voice changes after thyroidectomy: role of the external laryngeal nerve. Br Med J (Clin Res Ed). 1984;289:1412–5.

    Article  CAS  Google Scholar 

  26. Rossi RL, et al. Current results of conservative surgery for differentiated thyroid carcinoma. World J Surg. 1986;10:612–22.

    Article  CAS  PubMed  Google Scholar 

  27. Aluffi P, et al. Post-thyroidectomy superior laryngeal nerve injury. Eur Arch Otorhinolaryngol. 2001;258:451–4.

    Article  CAS  PubMed  Google Scholar 

  28. Lore JMJ, et al. Thirty-eight-year evaluation of a surgical technique to protect the external branch of the superior laryngeal nerve during thyroidectomy. Ann Otol Rhinol Laryngol. 1998;107:1015–22.

    Article  PubMed  Google Scholar 

  29. Reeve TS, et al. The recurrent and external laryngeal nerves in thyroidectomy. Med J Aust. 1969;1:380–2.

    CAS  PubMed  Google Scholar 

  30. Barczynski M, et al. Randomized controlled trial of visualization versus neuromonitoring of the external branch of the superior laryngeal nerve during thyroidectomy. World J Surg. 2012;36:1340–7.

    Article  PubMed  PubMed Central  Google Scholar 

  31. El-Kashlan HK, et al. Selective cricothyroid muscle reinnervation by muscle-nerve-muscle neurotization. Arch Otolaryngol Head Neck Surg. 2001;127:1211–5.

    Article  CAS  PubMed  Google Scholar 

  32. Bellantone R, et al. Is the identification of the external branch of the superior laryngeal nerve mandatory in thyroid operation? Results of a prospective randomized study. Surgery. 2001;130:1055–9.

    Article  CAS  PubMed  Google Scholar 

  33. Adour KK, Schneider GD, Hilsinger RLJ. Acute superior laryngeal nerve palsy: analysis of 78 cases. Otolaryngol Head Neck Surg. 1980;88:418–24.

    Article  CAS  PubMed  Google Scholar 

  34. Lifante JC, et al. A prospective, randomized trial of nerve monitoring of the external branch of the superior laryngeal nerve during thyroidectomy under local/regional anesthesia and IV sedation. Surgery. 2009;146:1167–73.

    Article  PubMed  Google Scholar 

  35. Aina EN, Hisham AN. External laryngeal nerve in thyroid surgery: recognition and surgical implications. ANZ J Surg. 2001;71:212–4.

    Article  CAS  PubMed  Google Scholar 

  36. Lennquist S, Cahlin C, Smeds S. The superior laryngeal nerve in thyroid surgery. Surgery. 1987;102:999–1008.

    CAS  PubMed  Google Scholar 

  37. Dionigi G, Dionigi R. Standardization of intraoperative neuromonitoring of recurrent laryngeal nerve in thyroid operation: to the editor. World J Surg. 2010;34:2794–5.

    Article  CAS  PubMed  Google Scholar 

  38. Sritharan N, et al. 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. Laryngoscope. 2014;. doi:10.1002/lary.24781.

    Google Scholar 

  39. Dionigi G, et al. Limits of neuromonitoring in thyroid surgery. Ann Surg. 2013;258:e1–2.

    Article  PubMed  Google Scholar 

Download references

Author information

Authors and Affiliations

  1. 1st Division of Surgery, Department of Surgical Sciences and Human Morphology, Research Center for Endocrine Surgery, University of Insubria (Como-Varese), via Guicciardini 9, 21100, Varese, Italy

    Gianlorenzo Dionigi

  2. Division of Breast and Endocrine Surgery, Department of Surgery, Minimally Invasive Surgery and Robotic Surgery Center, KUMC Thyroid Center, Korea University Anam Hospital, Korea University College of Medicine, Korea University, 73, Inchon-ro, Seongbuk-gu, Seoul, 136-705, South Korea

    Hoon Yub Kim

  3. Division of Thyroid and Parathyroid Endocrine Surgery, Department of Laryngology and Otology, Massachusetts Eye and Ear Infirmary, Harvard Medical School, Boston, USA

    Gregory W. Randolph

  4. Department of Otolaryngology-Head and Neck Surgery, Kaohsiung Medical University Hospital, Kaohsiung Medical University, Kaohsiung, Taiwan

    Che-Wei Wu & Feng-Yu Chiang

  5. Jilin Provincial Key Laboratory of Surgical Translational Medicine, Division of Thyroid Surgery, China-Japan Union Hospital of Jilin University, Changchun, Jilin Province, China

    Hui Sun & Xiaoli Liu

  6. Third Chair and Department of General Surgery, Jagiellonian University, Medical College, Krakow, Poland

    Marcin Barczynski

Authors
  1. Gianlorenzo Dionigi
    View author publications

    You can also search for this author in PubMed Google Scholar

  2. Hoon Yub Kim
    View author publications

    You can also search for this author in PubMed Google Scholar

  3. Gregory W. Randolph
    View author publications

    You can also search for this author in PubMed Google Scholar

  4. Che-Wei Wu
    View author publications

    You can also search for this author in PubMed Google Scholar

  5. Hui Sun
    View author publications

    You can also search for this author in PubMed Google Scholar

  6. Xiaoli Liu
    View author publications

    You can also search for this author in PubMed Google Scholar

  7. Marcin Barczynski
    View author publications

    You can also search for this author in PubMed Google Scholar

  8. Feng-Yu Chiang
    View author publications

    You can also search for this author in PubMed Google Scholar

Corresponding author

Correspondence to Hoon Yub Kim.

Ethics declarations

Conflict of interest

The authors have no conflicts of interest to disclosure, no other funding or financial relationship with surgical industry.

Rights and permissions

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Dionigi, G., Kim, H.Y., Randolph, G.W. et al. Prospective validation study of Cernea classification for predicting EMG alterations of the external branch of the superior laryngeal nerve. Surg Today 46, 785–791 (2016). https://doi.org/10.1007/s00595-015-1245-9

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1007/s00595-015-1245-9

Keywords

Search

Navigation