Inferior Approach: a Safe Method for Identification of Recurrent Laryngeal Nerve During Thyroidectomy

Abstract

The recurrent laryngeal nerve (RLN) and external branch of superior laryngeal nerve (EBSLN) and parathyroids have to be deliberately identified and preserved during each and every thyroidectomy. The RLN is vulnerable to injury at three sites during surgery. Various approaches have been adopted by surgeons the world over to identify and preserve the RLN. Here, we have adopted the ‘inferior approach’ (IA), which is an easy and a fruitful one. To safely identify and preserve the RLN in the neck using the inferior approach, an intra-operative analysis of RLN were conducted in 393 patients who underwent thyroidectomy for various indications at a tertiary care centre in North Malabar, Kerala, from January 2004 to December 2011 prospectively. The RLN was identified and preserved by inferior approach. Three hundred ninety-three cases were assessed (343 total and 50 hemi thyroidectomy); 358 and 375 RLN on left and right and 1 NRLN were identified. 64.88% of RLN was underneath, 7.14% was superficial to the main trunk and 27.97% was in between the branches of ITA. RLN enters the larynx mainly as a single trunk in 624 cases (85.11%), while it had branches in 110 cases (14.89%). Eighty-four cases (76.3%) had two branches and 26 cases (23.7%) had three branches. All nerves were identified and preserved using the inferior approach. We were unable to identify 2 RLN due to extensive adhesions and fibrosis of thyroiditis and malignancy. Fourteen patients had temporary hoarseness and no permanent vocal cord palsy was reported. Every thyroid surgeon should be aware of the anatomical variations of the RLN. Inferior approach is a safe technique for its identification and preservation.