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Updated: Mar 26, 2026

Identification and Protection of the Recurrent Laryngeal Nerve during Transoral Robotic Thyroidectomy
Published on: October 24, 2025
Nonrecurrent Laryngeal Nerve and Associated Anatomical Variations: The Art of Prediction
Marina Morais1, João Capela-Costa1, Luís Matos-Lima1
1Endocrine and Cervical Unit, General Surgery Department, São João Medical Center, Porto, Portugal.
Introduction:
A nonrecurrent laryngeal nerve (NRLN) is a rare anatomical variation in which the nerve enters the larynx directly off the cervical vagus nerve.
Case Report:
We present 2 patients who underwent thyroid surgery for benign disease. Intraoperatively, type 2a and 1 NRLN were identified. Due to the frequent association with a vascular abnormality, an ultrasound and a computed tomography were performed which showed a right aberrant subclavian artery with a retroesophageal course and a common trunk of the common carotids in both patients.
Discussion And Conclusion:
The presence of an NRLN is a major risk during surgical procedures and the surgeon should be aware of the possibility of its existence. NRLN may be associated with rare vascular anomalies, such as arteria lusoria and a bicarotid trunk. This paper reveals this association in 2 patients for the first time.
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