Laryngeal nerve morbidity in 1.273 central node dissections for thyroid cancer

Area of Science:

• Otolaryngology
• Endocrinology
• Surgical Oncology

Background:

• Recurrent laryngeal nerve (RLN) injury is a significant complication in thyroid surgery.
• Central neck dissection (CND) is often performed for advanced thyroid cancer, increasing the risk of RLN injury.
• Intraoperative neural monitoring (IONM) is used to minimize nerve damage.

Purpose of the Study:

• To determine the prevalence and mechanisms of RLN injury during CND for thyroid cancer.
• To compare the incidence of RLN injury between thyroidectomy and CND procedures.
• To analyze factors contributing to RLN lesions, including timing, mechanism, and nerve segment involved.

Main Methods:

• A retrospective analysis of 1,273 nerves at risk (NAR) undergoing CND with IONM.
• RLN lesions were categorized by timing (thyroidectomy vs. CND), injury type (segmental/diffuse), mechanism, severity, and location.
• Electromyography (EMG) parameters were recorded to assess nerve function.

Main Results:

• Overall RLN palsy occurred in 3.8% (49/1,273 NAR).
• Nerves were injured more frequently during thyroidectomy (25) than CND (8).
• Traction was the primary cause during thyroidectomy, while traction, entrapment, and thermal injury were equally frequent during CND. Permanent injuries occurred in 8% of cases.

Conclusions:

• RLN palsy remains a risk during CND, even with IONM.
• The incidence of RLN lesions is higher during the thyroidectomy phase compared to the CND phase.
• Understanding injury mechanisms is crucial for further prevention strategies in thyroid cancer surgery.