J Endocr Surg.  2021 Dec;21(4):79-85. 10.16956/jes.2021.21.4.79.

Sympathetic Inferior Laryngeal Anastomosing Branch: Our Two-Year Experience

• Parpounas C
• Yiallourides M
• Constantinides V

• KMID: 2525970
• DOI: http://doi.org/10.16956/jes.2021.21.4.79

Abstract

Purpose
The knowledge of sympathetic inferior laryngeal anastomosing branch (SILAB) is of great importance as it may mimic the non-recurrent laryngeal nerve (NRLN) leading to recurrent laryngeal nerve (RLN) damage in inexperienced hands. We describe our 2-year experience in SILAB recognition, describing the prevalence, diameter, and method of avoiding SILAB misinterpretation.
Methods
Consecutive patients undergoing total thyroidectomy with either prophylactic or therapeutic central compartment lymphadenectomy were included. Operative technique was standardized amongst 2 endocrine surgeons. Data was prospectively collected in a dedicated database. Demographic, pathological, operative, and biochemical parameters were collected, and subgroup outcomes were compared.
Results
One hundred thirty-three patients were included in the study, 100 were female (75.2%). Nineteen SILABS were recognized (19/202; 9.4%), 14 (14/99; 14.14%) on the right and 5 (5/103; 4.85%) on the left side. In a total of 6 cases (6/19; 31.5%), the SILAB diameter was similar to the RLN.
Conclusion
SILAB may not be as rare as previously thought. It not only branches to the RLN up to 2 cm from the level of the larynx but can branch more caudally up to the level of the clavicle. Intraoperative nerve monitoring is a very useful tool to avoid misinterpretation of SILAB to NRLN when used appropriately.

Keyword

Thyroid gland; Recurrent laryngeal nerve; Vagus nerve; Surgery