Voice outcomes following thyroid surgery: A study on non-nerve-related changes

Objectives: This study aimed to examine voice changes in patients without nerve damage after thyroid surgery and to analyze the effects of the scope of surgery, age, sex, and histopathological results on voice quality. Patients and Methods: A prospective study was conducted on patients who underwent thyroid surgery between April 2018 and April 2020. Harmonics-to-noise ratio (HNR), fundamental frequency (F0), jitter, shimmer, maximum phonation time, and voice-related quality of life (VRQOL) scores were evaluated at the preoperative stage and at the first-month postoperative stage. Patients were classified by surgery type, age, sex, and histopathological results, and changes in voice characteristics were examined. Results: The study included 77 patients (52 females, 25 males; mean age: 45.2±9.6 years; range, 18 to 62 years). Postoperative voice changes were observed in all thyroidectomy types, except for hemithyroidectomy. Patients who underwent surgery for malignant conditions experienced significant alterations in all voice parameters and VRQOL scores. In contrast, no significant changes were found in benign pathologies. Postoperatively, jitter and VRQOL scores significantly changed in females, while HNR changed in males. In patients over 50 years, F0, jitter, and HNR were affected, while jitter and shimmer were the altered parameters postoperatively in those under 50 years. Conclusion: After thyroidectomy, voice is influenced by the extent of surgery, patient demographics, and thyroid pathology. More extensive surgeries and malignant conditions lead to significant postoperative vocal changes. The influence of age and sex on voice varies and warrants further investigation.