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Updated: Nov 25, 2025

Identification and Protection of the Recurrent Laryngeal Nerve during Transoral Robotic Thyroidectomy
Published on: October 24, 2025
Comprehensive Comparison of Right and Left Recurrent Laryngeal Nerves in the Tracheoesophageal Groove
Michael J Herr1,2, J Macy Cottrell1, Madison Kahl1
112325 College of Medicine, University of Tennessee Health Science Center, Memphis, TN, USA.
Objective:
A left-sided cervical approach to esophageal mobilization is considered safer given the perceived oblique path and more lateral orientation of the right recurrent laryngeal nerve (RLN) in the tracheoesophageal groove. Given the risk of recurrent laryngeal nerve, the current study investigated if there are differences in right and left RLN location in the tracheoesophageal groove.
Methods:
Right and left RLNs were carefully exposed in human cadavers. Comparison of location was determined at tracheal rings 2, 4, and 6 using 3 parameters: depth of the RLN from the anterior margin of the tracheal ring, lateral distance of the RLN from the posterior margin of the tracheal ring, and distance of the RLN to the anterior midline trachea following the curvature of the trachea. Statistical analysis was used to determine differences between the right and left sides.
Results:
Compared with the right RLN, the left RLN was slightly over 1 mm deeper at the second tracheal ring. Despite this trend, there was no significant difference in RLN location between individual sides or as an aggregate for any of the 3 parameters at tracheal rings 2, 4, or 6.
Conclusions:
Careful characterization of RLN location precludes avoiding hoarseness, aphonia, and vocal cord paralysis. Counter to common surgical perception and educational beliefs, this study demonstrated that right and left RLN anatomical courses do not significantly differ along the trachea. Therefore, ensnarement on either side during a blind mobilization of the cervical esophagus is equally likely to occur.
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