Feasibility and accuracy of laryngeal ultrasound for the assessment of vocal cord mobility in children

Imaging Characteristics and Reference Values of the Vocal Cords in Chinese Adults Based on High-Frequency Ultrasound

OBJECTIVE

To elucidate the imaging characteristics of and establish reference values for measurement parameters of the vocal cords in healthy volunteers.

METHODS

A total of 1000 healthy Han Chinese adults (694 women) aged 18-79 y will be enrolled between October 2023 and April 2024. The length and width of vocal cord abduction and adduction and vocal cord thickness were measured, and the widening and shortening rates of vocal cord adduction were calculated as indicators of vocal cord motor function. The data were stratified by age group and sex. The correlations of vocal cord measurements with age, height, weight, BMI and BSA were analyzed.

RESULTS

The parathyroid section clearly revealed the vocal cord structure. Image quality decreases with age. Normal reference ranges (from the 2.5th to the 97.5th percentile) were established for vocal cord abduction length, adduction length, abduction width, adduction thickness, shortening rate and broadening rate based on data from 638 healthy adults: males: 13.98-28.17 mm, 11.33-21.21 mm, 2.90-5.66 mm, 5.65-7.44 mm, 3.16-6.18 mm, 9.97%-44.31% and 14.13%-137.78%, respectively; females: 12.55-19.42 mm, 9.59-14.80 mm, 3.40-4.80 mm, 5.65-7.90 mm, 3.40-4.90 mm, 10.05%-39.34% and 32.88%-102.66%, respectively. Vocal cord length, width, thickness, shortening rate and broadening rate were not correlated with age, height, weight, BMI or BSA.

CONCLUSION

This study summarized the characteristics of and initially established reference values for quantitative parameters of the vocal cords, ultimately providing reference values for the clinic.

Transcutaneous laryngeal ultrasound for long-term voice function and vocal fold evaluation after thyroidectomy: a prospective study

BACKGROUND

Transcutaneous laryngeal ultrasound (TLUSG) has come up as a practical alternative to laryngoscopy for the diagnosis of vocal fold palsy (VFP), as it's non-invasive and capable for dynamic real-time evaluation.

AIMS/OBJECTIVES

To assess the features of the vocal cord (VF) recovery process and the diagnostic significance of TLUSG for VFP during long-term follow-up on patients with voice disorders post-thyroidectomy.

MATERIAL AND METHODS

Fifty-seven patients with voice impairment following thyroidectomy were enrolled. The image features of VFs and the voice handicap index (VHI) scores were recorded at various intervals after surgery. Laryngoscopy was performed for comparison.

RESULTS

75.4%(43/57) patients recovered voice function as assessed by VHI, 41 (71.9%) patients demonstrated recovery by TLUSG. Eighteen patients underwent laryngoscopy, and 14 were identified as VFP. The ultrasonic images of VFP presented with different manifestations at different periods after thyroidectomy. The diagnostic accuracy of TLUSG increased from 77.8% to 88.9% over time, whereas that of VHI exhibited a decrease. TLUSG and Laryngoscope were highly consistent (κ = 0.679), as were the evaluations of two physicians.

CONCLUSIONS AND SIGNIFICANCE

The TLUSG is an effective alternative to laryngoscopy in patients with vocal dysfunction following thyroidectomy.

Comparison of the diagnostic and prognostic abilities of flexible laryngoscopy and dynamic digital radiography for vocal cord paralysis: A prospective observational study

BACKGROUND

Although flexible laryngoscopy (FL) is the reference modality for diagnosing vocal cord paralysis (VCP), FL involves patient discomfort and insertion intolerance. Dynamic digital radiography (DDR) with high spatial and temporal resolution is easier to use and less invasive when evaluating VCP.

METHODS

Seventy-eight patients underwent FL and DDR before and after neck surgery. Qualitative and quantitative vocal cord movement (VCM) evaluations were conducted. Patients with postoperative VCP were followed-up regularly.

RESULTS

DDR exhibited diagnostic performance with 67% sensitivity and 100% specificity. The cutoff for VCM was 2.4 mm, with DDR exhibiting 100% sensitivity and 78% specificity. All cords with transient VCP had positive VCM at both 3 weeks and 2 months. Additionally, 50% and 75% of cords with permanent VCP had negative VCM at 3 weeks and 2 months, respectively.

CONCLUSIONS

DDR is promising for the diagnosis of postoperative VCP and early prediction of permanent postoperative VCP.

Can Transcutaneous Laryngeal Ultrasonography Systematically Quantify Vocal Fold Movement?-A Feasibility Study

OBJECTIVES

Several studies have assessed adult vocal fold movement using transcutaneous laryngeal ultrasonography (TLUSG) during the perioperative period of thyroidectomy. However, the movement was not objectively quantified. This study aimed to provide a feasible and objective method for assessing vocal fold movement using TLUSG.

STUDY DESIGN

Feasibility study.

METHODS

TLUSG was performed during calm breathing and breath-holding in healthy adult volunteers. The morphology and anatomy of the larynx were observed and measured using an ultrasonic self-contained measurement function. At the end of the calm inspiratory and breath-holding phases, vocal fold angle, vocal fold length, distance from vocal process to the midline, distance from anterior vocal commissure to arytenoid cartilage, distance from false vocal fold to the midline, and distance from the anterior horn of thyroid cartilage to false vocal fold were measured. Data were analyzed using a t test (significance <0.05).

RESULTS

The ultrasonic images were satisfactory in all 40 healthy adult volunteers (age 19-35 years; body mass index 18.55-23.93 kg/m2; 20 men and 20 women). There were no significant differences in all laryngeal parameters between the left and right sides in both phases (P > 0.05). Moreover, all differences in laryngeal parameters between the end of the calm inspiratory phase and the breath-holding phase were statistically significant (P < 0.05), regardless of sex.

CONCLUSION

The relevant positional parameters of the vocal fold, arytenoid cartilage, and false vocal fold and their differences before and after vocal fold movement in healthy adult volunteers can be obtained objectively using TLUSG.