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

Gianlorenzo Dionigi, Hoon Yub Kim, Gregory W. Randolph, Che Wei Wu, Hui Sun, Xiaoli Liu, Marcin Barczynski, Feng Yu Chiang

Research output: Contribution to journalArticle

9 Citations (Scopus)


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.

Original languageEnglish
Pages (from-to)785-791
Number of pages7
JournalSurgery Today
Issue number7
Publication statusPublished - 2016 Jul 1



  • Cernea classification
  • External branch of the superior laryngeal nerve
  • Intraoperative nerve monitoring
  • IONM
  • Nerve injury
  • Neural monitoring study group

ASJC Scopus subject areas

  • Surgery

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