Published: 2022-07-25

Intra-operative discovery of nonrecurrent inferior laryngeal nerve: a report of 3 cases including one of left nonrecurrent inferior laryngeal nerve and literature review

Anwar Rahali, Rahal Mssrouri, Hamid Mohamed, Jalil Mdaghri, Khalid Lahlou, Said Benamr, Abdellatif Settaf


The nonrecurrent inferior laryngeal nerve (NRILN), a rare variant in the course of the inferior laryngeal nerve, passes transversely into larynx directly arising from the vagus nerve that increases the risk of damage to the nerve during thyroid and parathyroid surgery. We discussed clinical significance of non-recurrent laryngeal nerve during cervicotomy. Its importance was demonstrated in three clinical cases as well as the related literature reviews. All patients underwent bilateral thyroidectomy for a multinodular goiter. Two patients had identification of the NRILN on the right side. The third patient had the NRILN on the left side. The diagnosis of this anatomical variation was made per-operatively on all cases. The NRILN is an exceptional anomaly but overlooking its risk may lead to grave morbidity. This is a supplementary proof in favour of systematic dissection of the recurrent inferior laryngeal nerve (RILN) during all thyroid and parathyroid surgery.


Anatomy, Thyroidectomy, NRILN, Vocal cord palsy, Clinical cases

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