Non-Neural Post-Thyroidectomy Dysphonia

Sunday, September 29, 2024

2:36 PM – 2:42 PM EDT

Location: MBCC, 209

Disclosure(s):

Jeong-Yeon Ji, MD:

faculty for this accredited education activity has no relationship(s) with ineligible companies to disclose.

Seo Young Kim, MD:

faculty for this accredited education activity has no relationship(s) with ineligible companies to disclose.

Joonsik Yoon, MD:

faculty for this accredited education activity has no relationship(s) with ineligible companies to disclose.

Woo-Jin JEONG, MD, PhD:

faculty for this accredited education activity has no relationship(s) with ineligible companies to disclose.

Introduction: Post-thyroidectomy dysphonia (PTD) is commonly attributed to injuries to the recurrent laryngeal nerve (RLN) or the external branch of the superior laryngeal nerve (EBSLN), but can also arise from non-neural injuries. Postoperative electromyography (EMG) of the cricothyroid muscle is the gold standard for evaluating the integrity of the EBSLN. However, little research on PTD with non-neural injury exists, as most studies have not performed routine EMG. This study utilized postoperative EMG to investigate the long-term voice outcomes of non-neural PTD.

Methods: Patients undergoing primary thyroid surgery from December 2013 to December 2019 were included in the analysis. Voice evaluations were conducted preoperatively and at 3 days, 2 weeks, 1, 3, 6, and 12 months post-thyroidectomy. Postoperative EMG of the EBSLN was performed 2-3 months after surgery. Exclusion criteria included vocal fold pathology, previous superior laryngeal nerve injury, and previous brain or neck surgery.

Results: Among 559 patients with normal EMG, female patients' fundamental frequency (F0) decreased postoperatively, normalizing after 12 months. Male patients' F0 normalized within a month. When patients were categorized into 3 groups based on initial F0, each group showed varied F0 recovery timelines. The Voice Handicap Index-10 scores in females rose post-surgery, recovering after 6 months, while no significant changes were observed in males. Maximum phonation time significantly decreased 1 month after surgery for all groups, with no notable changes in Jitter, Shimmer, and Noise-to-Harmonic Ratio.

Conclusions: PTD can occur without RLN or EBSLN injury. This study’s findings on the characteristics of non-neural PTD are valuable for informed patient counseling in thyroid surgery.

Presenting Author(s)

Jeong-Yeon Ji, MD

Clinical Assistant Professor
Department of Otorhinolaryngology - Head and Neck Surgery, Seoul National University Bundang Hospital
Seongnam-si, Kyonggi-do, Republic of Korea

Disclosure(s):
faculty for this accredited education activity has no relationship(s) with ineligible companies to disclose.

Co-Author(s)

Seo Young Kim, MD

Fellow
Seoul National University Bundang Hospital
Seongnam-si, Kyonggi-do, Republic of Korea

Disclosure(s):
faculty for this accredited education activity has no relationship(s) with ineligible companies to disclose.
Joonsik Yoon, MD

Resident
Seoul National University Bundang Hospital
Songpa-Gu, Seoul-t'ukpyolsi, Republic of Korea

Disclosure(s):
faculty for this accredited education activity has no relationship(s) with ineligible companies to disclose.
Woo-Jin Jeong, MD, PhD

Professor
Seoul National University Bundang Hospital
Seoul, Kyonggi-do, Republic of Korea

Disclosure(s):
faculty for this accredited education activity has no relationship(s) with ineligible companies to disclose.

Senior Author(s)

Wonjae Cha, MD, PhD

Associate Professor
Department of Otorhinolaryngology - Head and Neck Surgery, Seoul National University Bundang Hospital
Seongnam-si, Kyonggi-do, Republic of Korea

Disclosure information not submitted.