The role of intraoperative neuromonitoring of recurrent laryngeal nerve during thyroidectomy: a comparative study on 1000 nerves at risk.
BACKGROUND
The role of intraoperative neuromonitoring of recurrent laryngeal nerve (RLN) during thyroidectomy has not been well established. The present study evaluates whether RLN injury can be reduced by the application of this technique during thyroidectomy in a single center.


METHODS
Of 1000 RLNs that were at risk of injury in 639 consecutive patients who underwent thyroidectomy, the outcome of 501 RLNs with the use of neuromonitoring was compared with that of 499 nerves that were operated by routine identification only. The incidences of RLN paralysis were compared between the 2 groups and the assigned risk subgroups.


RESULTS
Postoperative palsy was identified in 47 RLNs (4.7%), with complete recovery in 37 of 44 RLNs (84%) without documented injury. The overall incidence of postoperative RLN paralysis was significantly higher during thyroidectomy for malignancy (P = .025) and secondary thyroidectomy (P = .017). There was no significant difference in postoperative, transient, and permanent paralysis rates between the neuromonitoring and control groups. In subgroup analysis, the postoperative RLN palsy rate was higher during reoperative thyroidectomy (19% vs 4.6%; P = .019) in the control group but not in the neuromonitoring group (7.8% vs 3.8%; P > .05).


CONCLUSIONS
Neuromonitoring of the RLN during thyroid surgery could not be demonstrated to reduce RLN injury significantly, compared with the adoption of routine RLN identification. However, its application can be considered for selected high-risk thyroidectomies.
Chan
Wai-Fan
WF
Department of Surgery, University of Hong Kong Medical Centre, Queen Mary Hospital, Hong Kong, China.
Lang
Brian Hung-Hin
BH
Lo
Chung-Yau
CY
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002648:Child; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D016343:Monitoring, Intraoperative / Q000379:methods*; D011183:Postoperative Complications / Q000175:diagnosis / Q000209:etiology / Q000517:prevention & control; D012009:Recurrent Laryngeal Nerve / Q000502:physiology*; D061226:Recurrent Laryngeal Nerve Injuries; D012307:Risk Factors; D013965:Thyroidectomy / Q000009:adverse effects* / Q000379:methods; D016896:Treatment Outcome; D014826:Vocal Cord Paralysis / Q000175:diagnosis / Q000209:etiology / Q000517:prevention & control