Stepwise approach to preserve the external branch of superior laryngeal nerve during thyroidectomy

Abstract
Background
Most of the surgeons tend to avoid exposing and identification the external branch of the superior laryngeal nerve (EBSLN) during thyroidectomy. In this study, our aim is to assess sequential steps to ligate superior thyroid vessels safely away from the External branch of superior laryngeal nerve (EBSLN).

Methods
This prospective case series study was conducted on 60 patients going for either total or hemi thyroidectomy in a tertiary teaching hospital between January 2016 and June 2019. During thyroidectomy, firstly we skeletonized the upper pole of the thyroid gland by its capsular dissection followed by anterolateral down retraction of the superior pole. Then, entry and opening of the cricothyroid space and lastly clamping and ligating superior thyroid pedicle close to the upper pole away from EBSLN.

Results
This study included 60 cases; 19 total thyroidectomy and 41 hemi thyroidectomy with 79 superior thyroid vessels ligation and EBSLN at risk. In all patients, no evidence of superior laryngeal nerve (SLN) palsy or bleeding was detected. Postoperative video laryngoendoscopy showed apparently normal mobility, length, level, and position of the vocal folds with symmetry of the larynx. The patients’ voice showed no changes from preoperative evaluation in all studied patients at 3 months postoperative evaluation. No patients complained of any changes in their voice or voice activities.

Conclusion
The described stepwise approach for preservation of the EBSLN serves to completely remove the superior pole of the thyroid gland and ligate superior thyroid vascular pedicle without risk of SLN injury.