Analysis of Temporal Change in Voice Quality After Thyroidectomy: Single-institution Prospective Study

Voice Changes Without Laryngeal Nerve Alterations After Thyroidectomy: The Need For Prospective Trials - A Review Study

BACKGROUND

Thyroidectomy is a commonly performed surgical procedure that is offered for different thyroid pathologies. The most frequent complication after total thyroidectomy is transient or permanent hypoparathyroidism followed by transient or permanent recurrent laryngeal nerve palsy. Patients may experience voice impairment despite intact laryngeal nerve function. These patients are of special interest because they experience subjective symptoms which are difficult to measure and therefore to treat.

SUMMARY

The Voice Handicap Index (VHI) and VHI-10 are the most commonly used subjective questionnaires. Their results correlate with objective findings. Female sex, in particular after menopause, is a dominant factor for developing voice impairment after thyroidectomy. The extent of neck surgery and the weight and volume of the removed thyroid correlates directly with both objective and subjective voice impairment after surgery. Videolaryngostroboscopy should be considered to examine vocal cord pathologies in this patient group. Surprisingly, there are no studies showing that speech and voice therapy are beneficial for patients with voice alterations but with intact laryngeal nerves.

CONCLUSIONS

While recurrent laryngeal nerve (RLN) paralysis can be evaluated by objective exams postoperatively, we are still left with the issue of possible partial or complete external branch of superior laryngeal nerve (EBSLN) injury. It is therefore quite difficult to segregate neural (RLN and EBSLN) and non-neural voice change populations, regardless of the method of literature evaluation. Perhaps patients' perspectives on how they experience voice functionality should play a superior role in deciding which patients should be investigated further with laryngoscopy, acoustic or perceptual analysis, and which patients should be offered treatment.

Predictions for Three-Month Postoperative Vocal Recovery after Thyroid Surgery from Spectrograms with Deep Neural Network

Despite the lack of findings in laryngeal endoscopy, it is common for patients to undergo vocal problems after thyroid surgery. This study aimed to predict the recovery of the patient's voice after 3 months from preoperative and postoperative voice spectrograms. We retrospectively collected voice and the GRBAS score from 114 patients undergoing surgery with thyroid cancer. The data for each patient were taken from three points in time: preoperative, and 2 weeks and 3 months postoperative. Using the pretrained model to predict GRBAS as the backbone, the preoperative and 2-weeks-postoperative voice spectrogram were trained for the EfficientNet architecture deep-learning model with long short-term memory (LSTM) to predict the voice at 3 months postoperation. The correlation analysis of the predicted results for the grade, breathiness, and asthenia scores were 0.741, 0.766, and 0.433, respectively. Based on the scaled prediction results, the area under the receiver operating characteristic curve for the binarized grade, breathiness, and asthenia were 0.894, 0.918, and 0.735, respectively. In the follow-up test results for 12 patients after 6 months, the average of the AUC values for the five scores was 0.822. This study showed the feasibility of predicting vocal recovery after 3 months using the spectrogram. We expect this model could be used to relieve patients' psychological anxiety and encourage them to actively participate in speech rehabilitation.

Voice Disorders after Total Thyroidectomy: Prospective Evaluation by Patient Self-Assessment, Indirect Laryngoscopy and Ultrasonography

Voice alterations after thyroidectomy with mobile vocal folds are common. Ultrasonography has been used to assess the mobility of the vocal folds after thyroidectomy. Fifty-four patients underwent thyroidectomy. Indirect laryngoscopy, ultrasonography, and GRBAS (grade, roughness, breathiness, asthenia, strain) scoring were performed preoperatively, 3 days, 2 and 6 months, postoperatively. On the third postoperative day, the mobility of the vocal folds was preserved in 52 patients and pareses were recorded in 2 patients. All patients after thyroidectomy noted the presence of voice alteration in the absence of the postoperative paresis of the vocal folds. On the third postoperative day, the voice was impaired by all criteria of the GRBAS scale, but mainly due to roughness (85%). Sixth month postoperatively, 62% of the subjects considered the voice to be altered. Asthenia was observed in 39%. On the third postoperative day indirect laryngoscopy revealed the unchanged vocal folds, the edema and the shortening of one of the vocal folds in 56%, 42%, and 1.9%. Six months postoperatively, the vocal folds returned to their original form. Indirect laryngoscopy and ultrasonography had 100% concordance in assessing the mobility of the vocal folds. Patients with edema of the vocal folds had a significantly higher mean GRBAS grade than patients without edema. The mean GRBAS score decreased from 3.36 to 0.90, 3 days and 6 months, postoperatively. Voice alteration after thyroidectomy is always present. Postoperative edema represents a likely main cause of voice alteration and resolves within 6 months. Ultrasonography is recommended as alternative to indirect laryngoscopy in assessing of the vocal folds after thyroidectomy.

Objective Analysis Of Voice Quality In Patients With Thyroid Pathology

OBJECTIVE

The goal of this study is to analyze the voice in patients with thyroid pathology through two objective indexes with great diagnostic accuracy. Overall vocal quality was evaluated with the Acoustic Voice Quality Index (AVQI v.03.01) and the breathy voice with the Acoustic Breathiness Index (ABI).

DESIGN

Observational case-control study.

SETTING

Hospital Universitario Nuestra Señora de Candelaria.

PARTICIPANTS

Fifty-eight subjects, 29 controls and 29 thyroidectomy candidates.

MAIN OUTCOME MEASURES

All participants with thyroid pathology completed the Spanish version of Voice Handicap Index-10. Also, patient complaints relating to possible laryngeal dysfunction were assessed through closed questions. A sustained vowel and three phonetically balanced sentences were recorded for each subject (118 samples). AVQI v.03.01 and ABI were assessed using the Praat program. Two raters perceptually evaluated each voice sample by using the Grade parameter of GRABS scale.

RESULTS

Acoustic analysis shows that 55.17% of subjects present values above the pathological threshold of the AVQI, and 58.62% above that of the ABI. Results of the Student's test comparisons of the AVQI and ABI values between the control group and the thyroid group show significantly higher values of AVQI (t_[56]  = -3.85, p < .001) and ABI (t_[54.39]  = -4.82, p < .001) in thyroidectomy candidates.

CONCLUSION

A mild decrease in vocal quality is part of the symptomatology presented by thyroidectomy candidates.

Long-term voice quality outcome after thyroidectomy without laryngeal nerve injury: a prospective 10 year follow up study

PURPOSE

This study investigates the long-term voice outcome of thyroidectomy up to 10 years after the surgery using a longitudinal prospective study design.

METHODS

Eighteen participants (6 men and 12 women, mean age: 54 years) who underwent a thyroidectomy between September 2006 and May 2007 were included in this study. A voice assessment protocol consisting of subjective (videolaryngostroboscopic evaluation, auditory- perceptual evaluation, patients' self-report) and objective voice assessments (maximum performance task, acoustic analysis, voice range profile and Dysphonia Severity Index) was used to evaluate the participants' pre- and postoperative voice. Voice measurements were compared before and one week, six weeks, three months and 10 years after the surgery.

RESULTS

No significant differences over time in auditory-perceptual and objective voice parameters were found, except for shimmer. Only in the first postoperative condition, significantly more patients reported vocal complaints. A progressive amelioration of the vocal folds' movement patterns was observed in the postoperative conditions.

CONCLUSION

The findings of this small longitudinal prospective study suggest that thyroidectomy without laryngeal nerve injury does not cause a permanent deterioration of the laryngeal aspect or function, vocal fold behavior and the self-perceived, perceptual and objective vocal quality. The increase of the shimmer 10 years post-thyroidectomy may be related to vocal aging.

Influence of Recurrent Laryngeal Nerve Transient Unilateral Palsy on Objective Voice Parameters and on Voice Handicap Index after Total Thyroidectomy (Including Thyroid Carcinoma)

Introduction: Total thyroidectomy (TT) is one of the most common surgical endocrine surgeries. Voice impairment after TT can occur not only in patients with recurrent laryngeal nerve (RLN) transient paralysis, but also in cases of normal vocal cord mobility. Aim: To compare voice limits using a speech range profile (SRP) in patients before and 14 days after TT and to investigate the influence of the early results of voice quality after TT on the personal lives of patients. We focused on the perception of voice change before and shortly after TT. Materials and methods: A retrospective study, in the period 2018–2020, included 65 patients aged 22–75 years. We compared two groups of patients: group I (n = 45) (without RLN paresis) and group II (n = 20) (with early transient postoperative RLN paresis). Patients underwent video flexible laryngocopy, SRP, and Voice Handicap Index-30 (VHI-30). Results: In group I, the mean values of F_max (maximum frequency) and I_max (maximum intensity) decreased in women (both p = 0.001), and VHI-30 increased (p = 0.001). In group II after TT in women, the mean F_max and I_max values decreased (p = 0.005 and p = 0.034), and the frequency range of the voice was reduced from 5 to 2 semitones. The dynamic range of the voice was reduced by 3.4 dB in women and 5.1 dB in men.VHI-30 increased (p = 0.001). Conclusion: The study documented a worsening of the mean values of SRP, VHI-30, and voice parameters of patients in group II. Voice disorders also occurred in group I without RLN paresis. Non-paretic causes can also contribute to voice damage after TT. SRP and VHI-30 are suitable tools for comparing voice status in two groups of patients, including those with dysphonia. Our data support the claim that the diagnosis of a thyroid cancer does not necessarily imply a higher postoperative risk of impaired voice quality for the patient.

Evaluation of Voice and Vocal Fold Vibration after Thyroidectomy Using Two-Dimensional Scanning Digital Kymography and High-Speed Videolaryngoscopy

OBJECTIVE

Vocal dysfunction is one of the major factors that affect the health-related quality of life of patients after thyroidectomy. Conventionally, voice changes after thyroidectomy have been evaluated by videostroboscopy and acoustic analysis. Recently, two-dimensional scanning digital kymography (2D DKG) and high-speed videolaryngoscopy (HSV) have been developed and have shown usefulness in accurately evaluating vocal fold vibration. This study aimed to evaluate changes of vocal fold vibration and voice after thyroidectomy using 2D DKG and HSV.

MATERIALS AND METHODS

We evaluated the voice and vocal fold movement of 24 female patients who underwent thyroidectomy in a single tertiary hospital from December 2018 to October 2019. We obtained serial 2D DKG and HSV data one day before thyroidectomy, and 1 week and 1 month after surgery. We analyzed the peak glottal area of HSV, amplitude symmetry index, phase symmetry index, and open quotient using the 2D DKG data. The parameters were calculated at three levels of the vocal fold (line 1=anterior, line 2=middle, line 3=posterior). In the same period, we performed a voice analysis evaluating voice frequency, jitter, shimmer, and noise to harmonic ratio. We also assessed maximum phonation time and subjective voice changes with voice handicap index-10 questionnaires.

RESULTS

Highest frequency (F-high), frequency range (F-range), and fundamental frequency (F0) decreased at 1 week and 1 month after thyroidectomy compared with preoperative values (P = 0.003, 0.004, <0.001 and P = 0.002, 0.015, 0.001 at 1 week and 1 month, respectively). The open quotient of 2D DKG in lines 1 and 2 increased at 1 week after thyroidectomy (P = 0.011, 0.006) and recovered to preoperative levels at 1 month postoperatively (P = 0.189, 0.153). Other quantitative measures by 2D DKG and HSV did not show significant changes between the preoperative and postoperative periods. In a correlation analysis between vocal parameters from the acoustic analysis and the values obtained from 2D DKG and HSV, significant negative correlations were observed between peak glottal area and three factors (F-high, F-range, and F0) at 1 month after surgery (r = -0.589, -0.529, -0.708; P = 0.002, 0.008, <0.001, respectively). There were positive correlations between phase symmetry indexes in lines 1 and 2 and shimmer at 1 week after thyroidectomy (r = 0.489, 0.425; P = 0.015, 0.038, respectively). Phase symmetry index in line 3 showed a significant negative correlation with maximum phonation time at both 1 week and 1 month after surgery (r = -0.497, -0.439; P = 0.013, 0.032, respectively). However, there was no correlation between total score on the voice handicap index-10 questionnaires and quantitative measurements of vocal fold vibration.

CONCLUSION

2D DKG and HSV may provide important information on vocal fold vibratory patterns after thyroidectomy, and measurements made with them were correlated with maximal phonation time and acoustic parameters such as F-high, F-range, F0, shimmer.

Evaluation of one-year incidence of vocal dysfunction and associated demographic factors in thyroidectomy patients: A descriptive analytical study

Background

Voice changes are common complaint following thyroidectomy that might or might not be associated with laryngeal nerve damage. Objective: The aim of this study is to evaluate the effect thyroidectomy on voice alteration and its association with gender and age.

Methods

In this descriptive analytical study, patients who underwent thyroidectomy at (XXX) without laryngeal nerve damage were included. These patients were evaluated based on subjective (self-reported) and objective (videostroboscopy) voice assessment. The data was collected immediately after the surgery and 6 months after the surgery during the follow-up.

Results

Of 76 patients included, the mean age of patients was 46.3 year. 25 (43.4%) were males and 51 (56.6%) were female. 28.9% patients were presented with apparent damage to the vocal cords, of which 8 (10.5) had voice changes. There was no statistically significant difference between sex and postoperative vocal cord dysfunction (P = 0.592). However, in male gender, late postoperative voice changes were significantly more, p = 0.013. The age was also not associated with immediate or late postoperative changes and damage to vocal cords, p > 0.05.

Conclusion

Our study reported that male gender can be an important factor in deterring voice changes after thyroidectomy nonetheless, it can not predict the risk of vocal cord damage. Furthermore, age might not a risk factor either. Studies with greater sample size are required to confirm these findings.

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Voice changes are common complaint following thyroidectomy.

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That might or might not be associated with laryngeal nerve damage.

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Male gender can be an important factor in deterring voice changes after thyroidectomy.

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Studies with greater sample size are required to confirm these findings.

Comparison Between Patient-Perceived Voice Changes and Quantitative Voice Measures in the First Postoperative Year After Thyroidectomy: A Secondary Analysis of a Randomized Clinical Trial

Importance

Voice changes after thyroidectomy are typically attributed to recurrent laryngeal nerve injury. However, most postoperative voice changes occur in the absence of clinically evident vocal fold paralysis. To date, no study has compared the prevalence, duration, and consequences of voice-related disability from the patient perspective with use of quantitative vocal measures.

Objectives

To assess the quality-of-life consequences of postthyroidectomy voice change from the perspective of patients with thyroid cancer and to compare patient-perceived voice changes with changes in quantitative vocal variables at 5 time points in the first postoperative year.

Design, Setting, and Participants

This prospective mixed methods observational study within a randomized clinical trial occurred at the University of Wisconsin Hospital and Clinics. Participants were 42 patients with clinically node-negative papillary thyroid cancer without a preexisting vocal cord paralysis who were recruited and enrolled from outpatient clinics between June 6, 2014, and March 6, 2017, as part of the ongoing randomized clinical trial.

Intervention

Total thyroidectomy.

Main Outcomes and Measures

Semistructured interviews, symptom prevalence, and instrumental voice evaluations (laryngoscopy, phonation threshold pressure, Dysphonia Severity Index, and Voice Handicap Index) occurred at baseline (n = 42) and 2-week (n = 42), 6-week (n = 39), 6-month (n = 35), and 1-year (n = 30) postoperative time points.

Results

Participants had a mean age of 48 years (interquartile range, 38-58 years; age range, 22-70 years) and were mostly female (74% [31 of 42]) and of white race/ethnicity (98% [41 of 42]). Impaired communication was the primary theme derived from patient interviews from before thyroidectomy to after thyroidectomy. Voice changes were perceived by 24 participants at 2 weeks after thyroidectomy. After surgery, voice symptoms were prevalent and persisted for 50% (21 of 42) of participants out to at least 1 year of follow-up. Quantitative vocal perturbations were detected in the Dysphonia Severity Index and Voice Handicap Index at the 2-week follow-up but returned to baseline levels by the 6-week follow-up visit.

Conclusions and Relevance

Voice changes are common after surgery for papillary thyroid cancer and affect quality of life for many patients out to 1 year of follow-up. Directly querying patients about postoperative voice changes and questioning whether commonly used aerodynamic and acoustic variables detect meaningful voice changes are important in identifying patients whose quality of life has been affected by postthyroidectomy dysphonia.

Trial Registration

ClinicalTrials.gov Identifier: NCT02138214.