Objective Assessment of Vocal Function Changes Following Radiofrequency Ablation for Benign Thyroid Nodules

Background and/or Objectives: Radiofrequency ablation (RFA) is a treatment for benign thyroid nodules, but transient voice changes are a known complication often assessed subjectively. This study aimed to objectively evaluate changes in vocal function following RFA.

Design: Prospective observational study with repeated measures. Vocal function was assessed pre-RFA, immediately post-RFA, and three months post-RFA.

Setting : Outpatient clinic at a single medical center.

Participants : Seventy-five patients with benign thyroid nodules undergoing RFA were included. Inclusion criteria comprised age > 18, biopsy-confirmed benign and symptomatic nodules. Patients with pre-existing vocal pathologies were excluded. Mean age 46±13 years; 83% female.

Interventions: Ultrasound-guided RFA.

Main Outcome Measures: Aerodynamic function: maximum phonation time (MPT), s/z ratio. Acoustic function: jitter, shimmer, mean fundamental frequency (F0), noise-to-harmonic ratio (NHR).

Results: A significant MPT decrease was observed immediately post-RFA (11.25 s, P< 0.001) and at 3 months (12.40 s, P=0.007) compared to pre-RFA (13.88 s), suggesting potential dysphonia. Transient increases in jitter (P=0.013) and shimmer (P=0.039) were observed immediately post-RFA and resolved by 3 months. No significant changes were found in s/z ratio, F0, or NHR.

Conclusions: RFA affects acoustic and aerodynamic vocal function based on objective assessment. Acoustic changes are transient. Significant MPT reduction persists at 3 months. Objective vocal assessment is therefore crucial post-RFA to accurately monitor voice changes, track vocal recovery, and inform patient management and rehabilitation strategies.