Selective Laryngeal Examination: Sensitivity of Endocrine Surgeons in Screening Voice Abnormality

J Voice. 2019 Jan 3;S0892-1997(18)30395-3. doi: 10.1016/j.jvoice.2018.12.003. Online ahead of print.


Objectives: Selective laryngeal examination for patients undergoing thyroidectomy is recommended for patients with voice alterations, history of prior cervical or chest surgery, and patients with proven or suspected thyroid malignancy. The study objective is to measure the sensitivity of surgeons in detecting voice abnormalities in patients undergoing thyroidectomy, parathyroidectomy complicated with laryngeal nerve paralysis, or patients with known vocal cords palsy (VCP) due to other neck surgeries.

Design and setting: Descriptive cross-sectional study in a tertiary center.

Participants and methods: The subjects are 274 audio files of voices of patients undergoing thyroid, parathyroid surgeries, and known VCP due to other neck surgeries. Voice assessments were done by three endocrine surgeons (A, B, and C) with 20, 12, and 4 years of surgical experience.

Main outcome measures: Sensitivity and specificity of surgeon documented voice assessment in patients with underlying VCP. Subjects' acoustic analysis and Voice Handicap Index (VHI-10) were analyzed.

Results: Raters A, B, and C have sensitivity of 63.6%, 78.8%, and 66.7%, respectively. Inter-rater reliability shows substantial agreement (ƙ = 0.67). VHI-10 has sensitivity of 75.8% and strong correlation of 0.707 (p value <0.001) to VCP. Subjects with VCP have notably higher jitter, shimmer, and noise-to-harmonic ratio compared to normal subjects with sensitivity of 74.2%, 71.2%, and 72.7%, respectively.

Conclusions: The results for surgeons documented voice assessment did not reach the desired sensitivity for a screening tool for patients with underlying VCP. Other tools such as VHI-10 and acoustic analysis may not be used as standalone tools in screening patients with underlying VCP. Routine preoperative laryngeal examination may be recommended for all patients undergoing thyroid, parathyroid, or other surgeries that places the laryngeal nerves at risk.

Keywords: Acoustics; Endoscopy; Larynx; Vocal cords; Voice.