Neural monitoring of the superior laryngeal nerve in thyroid surgery

• Research type

  Research Study

• Full title

  Intra-operative monitoring of the external branch of the superior laryngeal nerve (EBSLN) during thyroid surgery: does it improve voice preservation?

• IRAS ID

  147216

• Contact name

  Paramita Baruah

• Contact email

  paramita.baruah@nhs.net

• Sponsor organisation

  The Royal Wolverhampton NHS Trust

• Duration of Study in the UK

  2 years, 0 months, 1 days

• Research summary

  Thyroid surgeons place an enormous amount of importance and rightly so to the preservation of the recurrent laryngeal nerve (RLN) during thyroidectomies. A good knowledge of the anatomy of the nerve and meticulous dissection technique and intra-operative identification of the nerve are crucial to the anatomic and functional integrity of the nerve. The use of intra-operative neural monitoring to aid the surgeon in the identification of the RLN has gained acceptance and is considered standard practice in several units.
  However, lesser emphasis has been placed historically on the identification and preservation of the external branch of the superior laryngeal nerve (EBSLN) during thyroid surgery. The EBSLN supplies the cricothyroid muscle that controls pitch variation during phonation. Unlike damage to the recurrent laryngeal nerve which manifests readily as vocal cord paralysis, intra-operative damage to EBSLN is difficult to assess post-operatively as visual assessment of the larynx is not indicative of the integrity of the nerve. Injury of the EBSLN can cause weakness or complete paralysis of the ipsilateral cricothyroid muscle. Patients may report a deeper voice or an inability to produce high pitched sounds. Patients may also complain of weakness, tightness of the voice, and require extra effort to speak. Of note, voice changes with EBSLN injury are subtle in the general population but can be devastating in patients who depend on their voice for a living. Importantly, EBSLN injury is reported in up-to 50% of thyroid surgery in contrast to 1-2% of recurrent laryngeal nerve injury during thyroid surgery. The new guidelines published in the Laryngoscope recommend routine intra-operative neural monitoring of EBSLN. We have a functional system in use currently for monitoring recurrent laryngeal nerve intra-operatively and propose to study the impact of monitoring the EBSLN using the same neural monitoring device to improve voice results following thyroid surgery.

• REC name

  West Midlands - South Birmingham Research Ethics Committee

• REC reference

  15/WM/0053

• Date of REC Opinion

  31 Mar 2015

• REC opinion

  Further Information Favourable Opinion