1Anatomy Division, Medical College, Jishou University, Jishou  416000, Hunan Province, China

2Anatomy Division, Shaoyang Medical College, Shaoyang  422000, Hunan Province, China

Changchu Wu, Associate professor, Anatomy Division, Medical College, Jishou University, Jishou  416000, Hunan Province, China Wu CC, Guo X, Li YW. Applied anatomy of the cervical region of the recurrent laryngeal nerve. Neural Regen Res 2008;3(6):663-5

Abstract

BACKGROUND AND OBJECTIVE: To avoid recurrent laryngeal nerve (RLN) injury during thyroid surgery, it is important to identify the nerve and to follow its projection carefully to discriminate it from the inferior thyroid artery.

DESIGN, TIME AND SETTING: All studies were performed at the Anatomy Division of Shaoyang Medical College from May 2003 to May 2004 with repeated measurement design.

MATERIALS: Fifty embalmed adult corpses, comprising 20 females and 30 males, were obtained by donation.

METHODS AND MAIN OUTCOME MEASURES: The projection, branches, and the relationship of the RLN to the inferior thyroid artery were observed.

RESULTS: The RLN in all cases ascended through the tracheoesophageal groove at the isthmus superior levels of the thyroid gland. However, the RLN in 14 cases were situated inferior to the isthmus of the thyroid gland; 11 cases were to the right side and 2 cases to the left side, projected in the tracheoesophageal groove, and ascended away from the groove after 4.5–6.5 mm. The RLN typically ramified at the thyroid isthmus plane (44 cases, 44% of all cases). The RLN branches were variable. Type 2 rami were most common in the RLN, accounting for 55%; the second most common was RLN branches with no rami. RLN braches with type 3 rami, 4 rami, and 5 rami were less common. Approximately 54% of nerves were situated behind the main branch artery. The nerves located adjacent to the arteries, and between the arterial branches, were similar; the former applied to 19 cases, accounting for 19%, whereas the latter applied to 18 cases, accounting for 18%. Left nerves behind the artery, and right nerves before the artery, were more common. There were significant differences between the left and right nerves (P < 0.01).

CONCLUSION: There was not a significant difference in the projection of the RLN, while a significant difference in the number of RLN branches existed. In addition, the anatomical relationship of the RLN and the inferior thyroid artery exhibited side differences.

Key Words: recurrent laryngeal nerve; inferior thyroid artery; applied anatomy

Full text:click