Compensatory Movement of Contralateral Vocal Folds in Patients With Unilateral Vocal Fold Paralysis.

OBJECTIVES(#br)Previous studies of subjects with unilateral vocal fold paralysis (UVFP) as observed in a positron emission tomography-computed tomography (PET-CT) examination have demonstrated false positive results in the contralateral cricoarytenoid, in which the metabolism may be higher. This area may also be the site of contralateral compensatory movement in these patients. In this study, we compared the adduction speed of the contralateral vocal folds in patients with UVFP and in healthy subjects as measured by the stroboscopic laryngoscope frame rate. This study aimed to explore the contralateral compensatory movement of the vocal folds in subjects with UVFP.(#br)METHODS(#br)(1) We collected visual data from 14 patients with UVFP and 14 healthy subjects through a stroboscopic laryngoscope. These subjects were divided into a vocal fold paralysis group and a control group, and we analyzed the excessive adduction of the contralateral vocal folds in the vocal fold paralysis group by examining vocal fold movement speed (pixels/s) as featured in a stroboscopic laryngoscope video. (2) We analyzed the uptake of 18-FDG in the posterior vocal fold from positron emission tomography-computed tomography imaging from four subjects with UVFP and 12 healthy subjects. An independent sample t test and a χ2 test were used to compare data.(#br)RESULTS(#br)Four subjects with UVFP had a higher metabolic rate in the contralateral cricoarytenoid joints, with a significant difference between the two groups, P 0.05.(#br)CONCLUSION(#br)Subjects with UVFP exhibited faster adduction compensation in the contralateral vocal folds, and the contralateral cricoarytenoid joint’s metabolism in subjects with UVFP was higher. These data may help clarify the diagnostic criteria for laryngeal nerve damage

Quantitative Measurement of the Three-dimensional Structure of the Vocal Folds and Its Application in Identifying the Type of Cricoarytenoid Joint Dislocation.

OBJECTIVE(#br)The objective of this study was to quantitatively measure the three-dimensional (3D) structure of the vocal folds in normal subjects and in patients with different types of cricoarytenoid dislocation. We will analyze differences in parameters between the groups and also determine if any morphologic parameters possess utility in distinguishing the type and the degree of cricoarytenoid dislocation.(#br)STUDY DESIGN(#br)This retrospective study was conducted using university hospital data.(#br)METHODS(#br)Subjects’ larynges were scanned using dual-source computed tomography (CT). The normal subjects were divided into deep-inhalation and phonation groups, and patients with cricoarytenoid joint dislocation were divided into anterior-dislocation and posterior-dislocation groups. Membranous vocal fold length and width were measured directly on the thin-section CT images. Vocal fold and airway 3D models were constructed using Mimics software and used in combination to measure vocal fold thickness, subglottal convergence angle, and oblique angle of the vocal folds.(#br)RESULTS(#br)The phonation group displayed a greater vocal fold width, greater oblique angle, thinner vocal folds, and a smaller subglottal convergence angle than those of the deep-inhalation group (P < 0.05). The anterior-dislocation group displayed a smaller oblique angle and subglottal convergence angle than the posterior-dislocation group (P < 0.05).(#br)CONCLUSIONS(#br)The 3D structure of the vocal folds during deep inhalation and phonation can be accurately measured using dual-source CT and laryngeal 3D reconstruction. As the anterior-dislocation group yielded negative values for the oblique angle and the posterior-dislocation group yielded positive values, the oblique angle of the vocal folds may possess utility for distinguishing the type and for quantitatively determining the degree of cricoarytenoid dislocation

Quantitative Measurement of the Three-dimensional Structure of the Vocal Folds and Its Application in Identifying the Type of Cricoarytenoid Joint Dislocation

Summary(#br)Objective(#br)The objective of this study was to quantitatively measure the three-dimensional (3D) structure of the vocal folds in normal subjects and in patients with different types of cricoarytenoid dislocation. We will analyze differences in parameters between the groups and also determine if any morphologic parameters possess utility in distinguishing the type and the degree of cricoarytenoid dislocation.(#br)Study Design(#br)This retrospective study was conducted using university hospital data.(#br)Methods(#br)Subjects’ larynges were scanned using dual-source computed tomography (CT). The normal subjects were divided into deep-inhalation and phonation groups, and patients with cricoarytenoid joint dislocation were divided into anterior-dislocation and posterior-dislocation groups. Membranous vocal fold length and width were measured directly on the thin-section CT images. Vocal fold and airway 3D models were constructed using Mimics software and used in combination to measure vocal fold thickness, subglottal convergence angle, and oblique angle of the vocal folds.(#br)Results(#br)The phonation group displayed a greater vocal fold width, greater oblique angle, thinner vocal folds, and a smaller subglottal convergence angle than those of the deep-inhalation group ( P < 0.05). The anterior-dislocation group displayed a smaller oblique angle and subglottal convergence angle than the posterior-dislocation group ( P < 0.05).(#br)Conclusions(#br)The 3D structure of the vocal folds during deep inhalation and phonation can be accurately measured using dual-source CT and laryngeal 3D reconstruction. As the anterior-dislocation group yielded negative values for the oblique angle and the posterior-dislocation group yielded positive values, the oblique angle of the vocal folds may possess utility for distinguishing the type and for quantitatively determining the degree of cricoarytenoid dislocation

Effects of Angle of Epiglottis on Aerodynamic and Acoustic Parameters in Excised Canine Larynges.

OBJECTIVES(#br)The aim of this study is to explore the effects of the angle of epiglottis (Aepi) on phonation and resonance in excised canine larynges.(#br)METHODS(#br)The anatomic Aepi was measured for 14 excised canine larynges as a control. Then, the Aepis were manually adjusted to 60° and 90° in each larynx. Aerodynamic and acoustic parameters, including mean flow rate, sound pressure level, jitter, shimmer, fundamental frequency (F0), and formants (F1’-F4’), were measured with a subglottal pressure of 1.5 kPa. Simple linear regression analysis between acoustic and aerodynamic parameters and the Aepi of the control was performed, and an analysis of variance comparing the acoustic and aerodynamic parameters of the three treatments was carried out.(#br)RESULTS(#br)The results of the study are as follows: (1) the larynges with larger anatomic Aepi had significantly lower jitter, shimmer, formant 1, and formant 2; (2) phonation threshold flow was significantly different for the three treatments; and (3) mean flow rate and sound pressure level were significantly different between the 60° and the 90° treatments of the 14 larynges.(#br)CONCLUSIONS(#br)The Aepi was proposed for the first time in this study. The Aepi plays an important role in phonation and resonance of excised canine larynges

Effects of Angle of Epiglottis on Aerodynamic and Acoustic Parameters in Excised Canine Larynges

Summary(#br)Objectives(#br)The aim of this study is to explore the effects of the angle of epiglottis (Aepi) on phonation and resonance in excised canine larynges.(#br)Methods(#br)The anatomic Aepi was measured for 14 excised canine larynges as a control. Then, the Aepis were manually adjusted to 60° and 90° in each larynx. Aerodynamic and acoustic parameters, including mean flow rate, sound pressure level, jitter, shimmer, fundamental frequency (F0), and formants (F1′–F4′), were measured with a subglottal pressure of 1.5 kPa. Simple linear regression analysis between acoustic and aerodynamic parameters and the Aepi of the control was performed, and an analysis of variance comparing the acoustic and aerodynamic parameters of the three treatments was carried out.(#br)Results(#br)The results of the study are as follows: (1) the larynges with larger anatomic Aepi had significantly lower jitter, shimmer, formant 1, and formant 2; (2) phonation threshold flow was significantly different for the three treatments; and (3) mean flow rate and sound pressure level were significantly different between the 60° and the 90° treatments of the 14 larynges.(#br)Conclusions(#br)The Aepi was proposed for the first time in this study. The Aepi plays an important role in phonation and resonance of excised canine larynges

Spatial Motion of Arytenoid Cartilage Using Dynamic Computed Tomography Combined with Euler Angles.

OBJECTIVE(#br)To investigate the feasibility of dynamic computed tomography in recording and describing the spatial motion characteristics of the arytenoid cartilage.(#br)METHODS(#br)Dynamic computed tomography recorded the real-time motion trajectory of the arytenoid cartilage during inspiration and phonation. A stationary coordinate system was established with the cricoid cartilage as a reference and a motion coordinate system was established using the movement of the arytenoid cartilage. The Euler angles of the arytenoid cartilage movement were calculated by transformation of the two coordinate systems, and the spatial motion characteristics of the arytenoid cartilage were quantitatively studied.(#br)RESULTS(#br)Displacement of the cricoid cartilage was primarily inferior during inspiration. During phonation, the displacement was mainly superior. When the glottis closed, the superior displacement was about 5-8 mm within 0.56 s. During inspiration, the arytenoid cartilage was displaced superiorly approximately 1-2 mm each 0.56 s. The rotation angle was subtle with slight rotation around the XYZ axis, with a range of 5-10 degrees. During phonation, the displacement of the arytenoid cartilage was mainly inferior (about 4-6 mm), anterior (about 2-4 mm) and medial (about 1-2 mm). The motion of the arytenoid cartilage mainly consisted of medial rolling, and there was an alternating movement of anterior-posterior tilting. The arytenoid cartilage rolled medially (about 20-40 degrees within 0.56 s), accompanied by anterior-posterior tilting (about 15-20 degrees within 0.56 s).(#br)CONCLUSION(#br)Dynamic computed tomography recordings of arytenoid cartilage movement can be combined with Euler transformations as a tool to study the spatial characteristics of laryngeal structures during phonation.(#br)LEVEL OF EVIDENCE(#br)4 Laryngoscope, 2019

Measurement of phonation threshold power in normal and disordered voice production.

International audienceOBJECTIVES: Phonation threshold pressure (PTP) and phonation threshold flow (PTF) are useful aerodynamic parameters, but each is sensitive to different disorders. A single comprehensive aerodynamic parameter sensitive to a variety of disorders might be beneficial in quantitative voice assessment. We performed the first study of phonation threshold power (PTW) in human subjects. METHODS: PTP and PTF were measured in 100 normal subjects, 19 subjects with vocal fold immobility, and 94 subjects with a benign mass lesion. PTW was calculated from these two parameters. In 41 subjects with a polyp, measurements were obtained before and after excision. Receiver operating characteristic (ROC) analysis was used to determine the ability of the three parameters to distinguish between controls and disordered groups. RESULTS: The PTW (p < 0.001), PTP (p < 0.001), and PTF (p < 0.001) were different among the three groups. All parameters decreased after polyp excision. PTW had the highest area under the ROC curve for all analyses. CONCLUSIONS: PTW is sensitive to the presence of mass lesions and vocal fold mobility disorders. Additionally, changes in PTW can be observed after excision of mass lesions. PTW could be a useful parameter to describe the aerodynamic inputs to voice production

Mandarin Chinese version of the Aging Voice Index

Abstract Objectives This study developed the Mandarin Chinese version of the Aging Voice Index (AVI), with preliminary validation of the scale for potential clinical applications. Study Design Scale development. Methods The experimental procedure involved: (1) cross‐cultural adaptation of the original AVI into the Mandarin Chinese version (CAVI); (2) evaluation by expert panel; (3) back translation; (4) pilot testing; (5) development of the final CAVI; (6) scale validation with 68 older adults of 60–89 years old (29 females and 39 males), 34 with voice disorders and 34 age‐matched with normal voice. Internal consistency reliability, test–retest reliability, content validity, criterion‐related validity, and discriminatory ability (diagnostic accuracy) of the CAVI were evaluated. Results There were high internal consistency (Cronbach's alpha = 0.9733), high test–retest reliability (intraclass correlation coefficient = 0.9578, p < 0.01), high content validity (content validity index = 0.9710), high criterion‐related validity (Pearson's r = 0.9439, p < 0.01 between CAVI and Voice Handicap Index‐10; r = 0.8070, p < 0.01 between CAVI and voice‐related quality of life [V‐RQOL]), and significant difference in CAVI scores between the two groups with huge effect size (t(34.69) = −11.59, Cohen's d = 2.81, p < 0.001). Receiver operating characteristic analysis revealed a high diagnostic accuracy of the CAVI, with an area under the curve of 0.9974 (p < 0.001) and a cut‐off score of 12.0 with 100% sensitivity and 97.1% specificity. Conclusion Our findings suggested that the CAVI could be a reliable and valid standardized self‐assessment questionnaire tool for clinical evaluation of the impact of voice problems specifically for Mandarin‐speaking older adults. Further studies should explore a full‐scale validation of the CAVI for being a standard clinical tool, including for older adults in Mainland China. Level of evidence 3b (case–control study)

Differentiating Arytenoid Dislocation and Recurrent Laryngeal Nerve Paralysis by Arytenoid Movement in Laryngoscopic Video

National Institutes of Health (NIH); National Natural Science Foundation of China [81070773, 81028004]; NIH from the National Institute on Deafness and other Communicative Disorders [R01 DC008153, F31 DC012495]Objective To present a new method of quantifying arytenoid movement during inspiration and determine if it can be used to distinguish arytenoid dislocation from vocal fold paralysis. Study Design Case series with chart review. Setting Retrospective study conducted in a university laboratory based on university hospital data. Subjects and Methods Endoscopic videos from 8 patients with dislocation and 5 patients with vocal fold paralysis diagnosed by electromyography were included. Vector analysis measured cuneiform movement, an indirect measurement of arytenoid movement, during 1 inspiration. Measurements normalized and not normalized to vocal fold length were evaluated. Interrater reliability (2 raters) and intrarater reliability (1 rater performing the analysis twice) were evaluated using intraclass correlation coefficient (ICC) analysis. Raters were blinded to subject group during analysis. Results Pixel-valued cuneiform movement was 81.16 +/- 25.62 for dislocation and 30.22 +/- 23.60 for paralysis (P = .019). Unitless cuneiform movement was 0.58 +/- 0.17 for dislocation and 0.24 +/- 0.18 for paralysis (P = .030). Interrater ICC was 0.942 for pixel-valued measurements and 0.962 for unitless measurements. Intrarater ICC was 0.909 for pixel-valued measurements and 0.881 for unitless measurements. Conclusions Both pixel-valued and unitless measures of arytenoid movement were significantly greater in arytenoid dislocation than vocal fold paralysis. Pixel-valued measurements were included to demonstrate the ability to make quantitative comparisons across subjects without precise knowledge of camera precision, provided position is approximately stable, as each measurement is inherently normalized by vocal tract length. Future studies will apply this new method of evaluating vocal fold immobility disorders on a larger scale and incorporate a more diverse group of etiologies

Phonation Threshold Flow Measurements in Normal and Pathological Phonation

NIH National Institute on Deafness and Other Communication Disorders [R01 DC008153]Objectives/Hypothesis: Phonation threshold flow (PTF) may provide a tool to assess laryngeal function and could differentiate between normal and pathological voices. Both polyps and nodules contribute to an increased PTF by creating an incomplete glottal closure and increased vocal fold mass and thickness. Study Design: Prospective study. Methods: The Kay Elemetrics Phonatory Aerodynamic System (PAS) (Kay Elemetrics Corp., Lincoln Park, NJ) was used to collect mean flow rate (MFR) and PTF measurements from 40 normal subjects, 21 patients with vocal fold nodules, and 23 patients with vocal fold polyps. Gender-based differences were assessed using a t test. The effect of vocal pathology on PTF and MFR was determined with an ANOVA. Diagnostic potential was evaluated using a receiver operation characteristics (ROC) analysis. Results: Both PTF (P = .047) and MFR (P = .008) were significantly affected by gender. Using a two-way ANOVA and correcting for gender differences, the influence of pathology on PTF was determined to be significant (P < .001). Post hoc tests found a significant difference between normal and polyp subjects (P < .001) but not normal and nodule subjects (P = .177) or nodule and polyp subjects (P = .246). ROC analysis found that PTF (area under the curve [AUC] = 0.691) and MFR (AUC = 0.684) had a similar diagnostic utility. Conclusions: PTF can be used to differentiate between normal and pathological voices. As a parameter that is experimentally sensitive to the biomechanical parameters providing its theoretical basis, it could be used clinically to analyze laryngeal functionality. Future research could focus on measuring PTF in other pathologies, such as paralysis or scarring, which would also affect the effort required to produce voice