Author(s)
Hung-Chun Chen
Tuan-Jen Fang
Yu-Chen Pei
Affiliation(s)
Chang Gung Memorial Hospital
Abstract:
Objective: To identify the risk factors of unilateral vocal fold paralysis (UVFP) after thyroid surgery and stratify preoperative patient status so as to justify the subgroup of patients that are especially in need of new nerve monitoring technologies. Study design: Retrospective study. Methods: From April 2011 to February 2016, patients with UVFP caused by thyroid-related surgeries in a tertiary referral medical center in Taiwan were reviewed. UVFP was diagnosed through laryngoscopy and laryngeal electromyography (LEMG). Factors including patient demographics, surgery types, and the entity of thyroid lesions were evaluated. Results: Sixty out of 2637 patients received thyroid surgery (2.3%) were complicated with UVFP. The incidence of UVFP differed among surgery types (p<0.001) with the highest caused by total thyroidectomy with neck dissection (10.0%). The incidence of UVFP was comparable among age, gender, comorbidity and tumor status. Twenty out of the UVFP patients (33%) also had neuropathy in the external branch of superior laryngeal nerve (eSLN), among whom total thyroidectomy and neck dissection had the highest incidence (3.9%) (p<0.001). Conclusion: The total thyroidectomy with neck dissection has the highest risk for UVFP and also for eSLN injury. Therefore, intraoperative nerve monitoring and novel surgery technologies are especially needed for patients receiving total thyroidectomy with neck dissection. Key Words: Thyroid surgery, unilateral vocal fold paralysis, external branch of superior laryngeal nerve, intraoperative nerve monitoring. Level of Evidence: 4.