A Study of Variations in the Relation of Recurrent Laryngeal Nerve to the Thyroid Gland and Its Vascular Pedicles

Abstract

Introduction: One of the important nerves in the neck area is the recurrent laryngeal nerve. Due to the anatomical variation in the course and the branching pattern the nerve is more prone to get injured during neck surgeries. This is due to lack of understanding about the anatomical variation of the recurrent laryngeal nerve, the course and branching pattern.

Aim: To study the variation in the course of recurrent laryngeal nerve to the thyroid gland and its vascular pedicle.

Methods: This prospective hospital-based study was undertaken in the Department of ENT at Sri Manakula Vinayagar Medical College and Hospital in Madagadipet, Puducherry. A total of 69 patients were included in the study. The study was conducted for 18 months, from November 2022 to May 2024. Throughout the investigation, each side of the neck was handled as an independent unit. This study looked at the entry into the larynx, the inferior thyroid artery, the course of recurrent laryngeal nerve, the branching pattern, and the relation to the thyroid gland.

Results: A total of 69 study participants participated in the study. And among them, 64 were patients, and 5 were cadavers from the anatomy lab. The mean age of the patients was found to be 46.68 + 12.46 years. The recurrent laryngeal nerve's location in the neck (p-0.335), its branching pattern between the two sides (p-0.427), and its position with respect to the Berry ligament (p-0.962) were all shown to be insignificantly different by the study. Concurrently, the study found a statistically significant variation in the recurrent laryngeal nerve's correlation with the tubercle of Zuckerkandl (p-0.009) and the inferior thyroid artery (p-0.002). Approximately 11.5% of the patients experienced hypocalcemia during the post-operative phase, for which conservative measures were taken.

Conclusion: The operating surgeon should have a thorough knowledge of the anatomical variation in the recurrent laryngeal nerves to avoid any adverse events during the surgical procedures. This helps prevent unnecessary complications and improves the patient's quality of life.