False Vocal Folds Research Articles

Quantitative Assessment of True Vocal Fold Movement by the Lateral-Approach Laryngeal Ultrasonography: A Pilot Study

Background/ObjectivesUltrasonography is a new method for subjective and qualitative assessment of true vocal fold movement, and true vocal fold visualization with the lateral approach could be better than that with the anterior approach. Our aim was to explore the feasibility of the lateral-approach ultrasonography in objective and quantitative assessment of true vocal fold movement. MethodsThe lateral-approach laryngeal ultrasonography was performed during calm breathing and breath-holding in young healthy adult volunteers. The morphology and anatomical position of false vocal fold, true vocal fold and arytenoid cartilage were observed and measured through the ultrasonic self-contained measurement function. All parameters, including the distance from false vocal fold to thyroid cartilage lamina, true vocal fold length, and the distance from true vocal fold to thyroid cartilage lamina, were obtained at the end of the calm inspiratory and breath-holding phases. Data were analyzed using a t test (P <0.05). ResultsForty healthy adult volunteers (age 20-34 years, Body Mass Index 19.5-23.8 kg/m2, 20 males and 20 females) with satisfactory ultrasonic images were included in the study. There were no significant differences in all laryngeal parameters between the left and right sides in either phase (P > 0.05). From the end of the calm inspiratory phase to the breath-holding phase, changes in all laryngeal parameters were significantly different (P < 0.05), regardless of gender. ConclusionsThis study demonstrated that the lateral-approach laryngeal ultrasonography seemed feasible to quantify and objectively assess true vocal fold movement, utilizing differences between laryngeal parameters before and after true vocal fold movement.

The larynx in 3 dimensions: A digital anatomical model derived from radiographic imaging, refined with peer-reviewed literature, and optimized with medical illustration

ObjectivesDevelopment of an anatomically accurate three-dimensional (3D) digital model of the human larynx derived from published literature and radiographic imaging. Materials and MethodsThe laryngeal framework was segmented from a computed tomography (CT) angiogram of a healthy 29-year-old female. Data derived from published anatomical studies were compiled to provide additional anatomical detail to each structure. Anatomical details beyond the resolution of the imaging study or which could not be elucidated from the study were refined according to descriptions in the anatomic literature. The 3D model was refined by the medical illustrator, and its mesh was reformatted to optimize online viewing and manipulation. ResultsDue to the small size of the laryngeal muscles, there was no attempt to segment these muscles using radiographic imaging. All intrinsic laryngeal muscles were generated de novo, as were the superior laryngeal nerve and recurrent laryngeal nerve. CT imaging was utilized to generate meshes of the hyoid bone, epiglottis, thyroid cartilage, cricoid cartilage, and thyrohyoid membrane. Additionally, the airway space was segmented to provide size and spatial location to the vallecula, false vocal folds, true vocal folds, piriform sinus, subglottis, and a scaffold for the mucosa. These meshes were processed to limit radiographic artifact and serve as a foundation for the construction of the remainder of the laryngeal anatomy. The model was uploaded to a 3D repository, which can be accessed here (https://shorturl.at/nJPYZ). ConclusionThe larynx is a highly specialized organ essential for speech, swallowing, and airway protection. This study describes a digital 3D model of the larynx, created by combining radiographic imaging with critical review of anatomic literature. Utilizing the expertise of neuroradiology, laryngeal surgery, and medical illustration, we highlight surgically-relevant anatomic relationships and important aspects to consider during laryngeal surgery.

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

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. Feasibility study. 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). The ultrasonic images were satisfactory in all 40 healthy adult volunteers (age 19-35 years; body mass index 18.55-23.93kg/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. 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.

The influence of source-filter interaction on the voice source in a three-dimensional computational model of voice production.

The goal of this computational study is to quantify global effects of vocal tract constriction at various locations (false vocal folds, aryepiglottic folds, pharynx, oral cavity, and lips) on the voice source across a large range of vocal fold conditions. The results showed that while inclusion of a uniform vocal tract had notable effects on the voice source, further constricting the vocal tract only had small effects except for conditions of extreme constriction, at which constrictions at any location along the vocal tract decreased the mean and peak-to-peak amplitude of the glottal flow waveform. Although narrowing in the epilarynx increased the normalized maximum flow declination rate, vocal tract constriction in general slightly reduced the source strength and high-frequency harmonic production at the glottis, except for a limited set of vocal fold conditions (e.g., soft, long vocal folds subject to relatively high pressure). This suggests that simultaneous laryngeal and vocal tract adjustments are required to maximize source-filter interaction. While vocal tract adjustments are often assumed to improve voice production, our results indicate that such improvements are mainly due to changes in vocal tract acoustic response rather than improved voice production at the glottis.

The effect of vocal tract semi-occlusion on the voice source and implications for voice therapy

Semi-occluded vocal tract exercises are often used in voice therapy to improve voice production. It is generally assumed that by enhancing source-filter interaction, such vocal exercises improve vocal efficiency while minimizing vocal fold collision. The goal of this computational study is to quantify such effects of source–filter interaction on the voice source. Voice simulations were performed with vocal tract constriction at various locations (false vocal folds, aryepiglottic folds, pharynx, oral cavity, and lips). The results showed that effects of vocal tract constriction on the voice source were generally small except for conditions of extreme constriction, at which constrictions at any location along the vocal tract decreased the mean and peak-to-peak amplitude of the glottal flow waveform. In general, source-filter interaction that reduced vocal fold contact pressure also decreased sound pressure level, thus making it impractical when targeting a desired output vocal intensity. While source–filter interaction is often assumed to improve vocal efficiency and economy, our results indicate that such improvements are mainly due to improvement in the filter rather than the voice source at the glottis. It is possible that speakers make additional laryngeal adjustments during vocal exercises, which may also contribute to the therapeutic benefits of such exercises.

Using a vertical three-mass computational model of the vocal folds to match human phonation of three adult males.

Computer models of phonation are used to study various parameters that are difficult to control, measure, and observe in human subjects. Imitating human phonation by varying the prephonatory conditions of computer models offers insight into the variations that occur across human phonatory production. In the present study, a vertical three-mass computer model of phonation [Perrine, Scherer, Fulcher, and Zhai (2020). J. Acoust. Soc. Am. 147, 1727-1737], driven by empirical pressures from a physical model of the vocal folds (model M5), with a vocal tract following the design of Ishizaka and Flanagan [(1972). Bell Sys. Tech. J. 51, 1233-1268] was used to match prolonged vowels produced by three male subjects using various pitch and loudness levels. The prephonatory conditions of tissue mass and tension, subglottal pressure, glottal diameter and angle, posterior glottal gap, false vocal fold gap, and vocal tract cross-sectional areas were varied in the model to match the model output with the fundamental frequency, alternating current airflow, direct current airflow, skewing quotient, open quotient, maximum flow negative derivative, and the first three formant frequencies from the human production. Parameters were matched between the model and human subjects with an average overall percent mismatch of 4.40% (standard deviation = 6.75%), suggesting a reasonable ability of the simple low dimensional model to mimic these variables.

An Unusual Laryngeal Foreign Body in Adult: Denture

Background: Foreign bodies in the larynx are reported quite rarely, with a prevalence of around 4% among patients, especially geriatrics, and represent an acute airway emergency with significant morbidity and mortality rate. Objective: This case report aimed to provide information on managing the extraction of foreign bodies and the accompanying problems. Discussion: A 49-year-old man with a history of wearing dentures was admitted to the emergency room. The patient complained of a hoarse voice upon waking up, painful swallowing, and a lumpy sensation in his throat, but he had no chest pain, cough, nausea, or vomiting. An indirect laryngoscopy examination revealed a foreign body lodged in the anterior rima glottis, impeding the mobility of the vocal folds. Under general anesthesia, emergency direct laryngoscopy, evacuation, and tracheoscopy were performed. It was observed that a foreign denture body was lodged in the larynx and was evacuated using grasping forceps. Post-evacuation, the vocal folds were swollen, with a false vocal fold hematoma, posterior subglottic laceration, and no active bleeding. Conclusion: Foreign bodies in the larynx must be prompted and gently removed because it leads to life-threatening. In suspected swallowed foreign bodies, plain radiographs are the initial imaging approach. Inhalational or intravenous induction is operated to administer the general anesthetic, along with the maintenance of spontaneous ventilation.

A Case of Inverted Papilloma in the False Vocal Fold Coexisting With Fungiform Papillomas of the True Vocal Fold

Inverted papilloma is a pathologic subtype of papilloma that mainly occurs in the sinonasal tract. Laryngeal inverted papilloma is extremely rare, and only a few cases have been reported so far. A 78-year-old male visited our clinic complaining of voice change that lasted five months. The rigid laryngoscopy showed multiple exophytic papillomatous masses in both vocal folds, and the left false vocal fold showed slight protruding appearance without a definite mass shadow. We performed laryngeal microsurgery with CO&lt;sub&gt;2&lt;/sub&gt; laser. While the masses in both true vocal folds were pathologically diagnosed as fungiform papillomas, the left false vocal fold was diagnosed as an inverted type. We report this very rare and unique case of laryngeal papilloma with a relevant literature review.

Quantification of False Vocal Fold Hyperfunction During Quiet Breathing in Muscle Tension Dysphonia.

False vocal fold (FVF) hyperfunction during phonation is thought to be a diagnostic sign of primary muscle tension dysphonia (pMTD). However, hyperfunctional patterns with phonation are also observed in typical speakers. This study tested the hypothesis that FVF posturing during quiet breathing, as measured by the curvature of FVF, could differentiate patients with pMTD from typical speakers. Laryngoscopic images were collected prospectively in 30 subjects with pMTD and 33 typical speakers. Images were acquired at the end of expiration and maximal inspiration during quiet breathing, during sustained /i/, and during loud phonation before and after a 30-min vocal loading task. The FVF curvature (degree of concavity/convexity) was quantified using a novel curvature index (CI, >0 for hyperfunctional/convex, <0 for "relaxed"/concave) and compared between the two groups. At end-expiration, the pMTD group adopted a convex FVF contour, whereas the control group adopted a concave FVF contour (mean CI 0.123 [SEM 0.046] vs. -0.093 [SEM 0.030], p = 0.0002) before vocal loading. At maximal inspiration, the pMTD group had a neutral/straight FVF contour, whereas the control group had a concave FVF contour (mean CI 0.012 [SEM 0.038] vs. -0.155 [SEM 0.018], p = 0.0002). There were no statistically significant differences in FVF curvature between groups in either the sustained voiced or loud conditions. Vocal loading did not change any of these relationships. A hyperfunctional posture of the FVFs during quiet breathing especially at end-expiration may be more indicative of a hyperfunctional voice disorder than supraglottic constriction during voicing. 3 Laryngoscope, 133:3449-3454, 2023.

High-Speed Image Analysis Comparing Loading of Vocal Folds During Coughing and Phonation: A Case Study

Coughing is related to voice problems, since it involves firm glottal closure, fast glottal opening, and high subglottic pressure and flow rate. In this study, the glottal area variation and movements of laryngeal structures during coughing and phonation are compared. High-speed laryngoscopy recordings were made of a normophonic male participant with a healthy larynx producing a neutral vowel and coughing. Oral air pressure was registered in a mouthpiece, through which an endoscope was inserted into the pharynx. Electroglottography, acoustic, and pressure signals were recorded simultaneously. The glottal width variation at the membranous and cartilaginous parts of the glottis was derived from the high-speed images, and the strong vibration of the false vocal folds was also registered. In coughing, compared to ordinary vowel phonation in nearly the same sound pressure level (93-94 dB6cm), the glottal width was 25% larger at the middle of the vocal folds, the maximum glottal opening velocity was 39% higher, and the maximum glottal width declination rate during glottal closing was up to three times higher. The maximum acceleration was 40% higher, and the maximum deceleration was 47% higher. Fundamental frequency f0 was the highest (ca. 400 Hz) at the beginning of the first phase of a typical coughing process. During the last part of the coughing process, f0 decreased from ca. 250 Hz to ca. 85 Hz at the phonation offset. The remarkable increase in maximum glottal width declination rate implies much higher vocal fold loading in coughing compared to phonation.

Auditory-perceptual Parameters as Predictors of Voice Acoustic Measures

Much research has examined the relationship between perceptual and acoustic measures. However, little is known about the prediction values of perceptual measures on an acoustic parameter. This study utilized simulated and disordered voice samples to investigate the prediction values of breathiness, roughness, and strain ratings on the selection of some time-based and spectral-based measures of voice quality. This study retrospectively analysed two sets of precollected data. The experimental data had been collected from nine trained speakers manipulating false vocal fold activity, true vocal fold mass, and larynx height. The voice-disordered data had been extracted from a clinical database for 68 patients with muscle tension voice disorders (MTVD). Both data sets had been perceptually rated for breathiness, roughness, and strain. Voice samples (prolonged vowel /ɑ/ and Rainbow Passage readings) had undergone acoustic analysis using Praat for harmonics-to-noise ratio (HNR) and the program "Analysis of Dysphonia in Speech and Voice" (ADSV) for cepstral peak prominence (CPP), Cepstral/Spectral Index of Dysphonia (CSID), and Low/High spectral ratio (L/H ratio). Perceptual parameters were regressed against these acoustic measures to test their prediction values. Reliability data showed satisfactory intra- and inter-reliability of perceptual ratings for both data sets. Breathiness significantly predicted CPP (both vocal tasks) and CSID (Rainbow Passage) in experimental data and predicted all the acoustic measures in MTVD data. Roughness significantly predicted HNR, CPP, and CSID in experimental data, and CPP (Rainbow Passage) and CSID (both vocal tasks) in MTVD data. Strain (both vocal tasks) significantly predicted L/H ratio in both data sets. Breathiness ratings predicted selection of HNR, CPP and CSID; roughness ratings predicted selection of CPP and CSID, and strain ratings predicted L/H ratio.

Assessment of Laryngeal Sensory Function using a Tactile Aesthesiometer in Healthy Adults.

Laryngeal sensory function in healthy adults was assessed through the delivery of tactile stimuli using Cheung-Bearelly monofilaments. 37 healthy adults were recruited with 340 tactile stimuli analyzed. Four calibrated tactile stimuli were delivered to three laryngeal sites: false vocal fold (FVF), aryepiglottic fold (AEF), and lateral pyriform sinus (LPS). Primary outcome was the elicitation of laryngeal adductor reflex (LAR). Secondary outcomes were gag, patient-reported laryngeal sensation (PRLS), and perceptual strength. Analysis was performed with mixed effects logistic regression modeling. Positive LAR was observed in 35.7%, 70.2%, and 91.2% of stimuli at LPS, AEF, and FVF respectively. LAR rates were significantly associated with laryngopharyngeal subsite (p< 0.001), tactile force (p= 0.001), age (p= 0.022) and sex (p= 0.022). LAR, gag, PRLS, and perceptual strength significantly increased as a more medial laryngeal subsite was stimulated and as stimulus force increased. Each of the ten years of age increase was associated with 19% reduction in odds of LAR (aOR=0.81, 95% CI [0.68, 0.97]; p= 0.022). Male gender was associated with a 55% reduction in odds of LAR (aOR=0.45, 95% CI [0.23, 0.89]; p= 0.022). LAR elicitation capability decreases in the male gender, aging, and a more lateral subsite. This study provides insight into the pathophysiology of hypo- and hyper-sensitive laryngeal disorders and is paramount to making accurate diagnostic assessments and finding novel treatment options for various laryngological disorders. Laryngoscope, 133:2525-2532, 2023.

Computational Estimates of Pitch Height and Pitch Strength in Dysphonic Voices

<h3>Research Objectives</h3> To evaluate the utility of automated computational estimates of pitch height and pitch strength in characterizing dysphonic voices that have glottal (i.e., true vocal folds) and supraglottal (e.g., false vocal folds), vibratory sources (GVS and SGVS). Furthermore, the utility of such pitch-based measures (Zwicker & Fastl, 1990) in characterizing and differentiating these voice signals that vary in periodicity (Type I, II, and III) was also tested (Titze, 1994). <h3>Design</h3> Repeated measures. <h3>Setting</h3> University. <h3>Participants</h3> Dysphonic voice samples (sustained /a/ and sentence) from 30 adults with GVS (10 per signal type) and 30 adults with SGVS (10 per signal type) were selected from a large database through stratified-random sampling. Pitch height and pitch strength were estimated from Auditory-Sawtooth Waveform Inspired Pitch Estimator Prime (Aud-SWIPE', Camacho, 2012) algorithm and compared with conventional fundamental frequency (f0) estimates from PRAAT software (Boersma, 2022). <h3>Interventions</h3> Not Applicable. <h3>Main Outcome Measures</h3> It is hypothesized that dysphonic voices with SGVS will have lower pitch height and pitch strength than GVS due to the inherent differences in anatomical structures of vibration and their associated physiological properties (Alipour & Karnell, 2014; Schwarz et al., 2011). It is also hypothesized that there will be a significant difference in pitch height and pitch strength between the Type I, II, and III voice signals varying in periodicity (Anand et al., 2021). <h3>Results</h3> Pitch height and pitch strength were higher in GVS compared to SGVS. Estimates of pitch height and f0 from were highly correlated and were in close agreement for Type I signals compared to other signal types where PRAAT was unable to provide f0 trace for some voices. Pitch strength was highest for Type I signals and lowest for Type III signals. <h3>Conclusions</h3> Pitch height and pitch strength can be measured in all dysphonic voices irrespective of signal periodicity. <h3>Author(s) Disclosures</h3> Supraja Anand receives salary from the University of South Florida.

Localization of TRPV3/4 and PIEZO1/2 sensory receptors in murine and human larynges.

The primary aim of this study was to identify expression of TRPV3 and TRPV4 chemoreceptors across perinatal and adult stages using a murine model with direct comparisons to human laryngeal mucosa. Our secondary aim was to establish novel cell expression patterns of mechanoreceptors PIEZO1 and PIEZO2 in human tissue samples. In vivo. We harvested murine laryngeal tissue to localize and describe TRPV3/4 endogenous protein expression patterns via immunofluorescence analyses across two developmental (E16.5, P0) and adult (6 weeks) timepoints. Additionally, we obtained a 60-year-old female larynx including the proximal trachea and esophagus to investigate TRPV3/4 and PIEZO1/2 protein expression patterns via immunofluorescence analyses for comparison to murine adult tissue. Murine TRPV3/4 expression was noted at E16.5 with epithelial cell colocalization to supraglottic regions of the arytenoids, aryepiglottic folds and epiglottis through to birth (P0), extending to the adult timepoint. Human TRPV3/4 protein expression was most evident to epithelium of the arytenoid region, with additional expression of TRPV3 and TRPV4 to proximal esophageal and tracheal epithelium, respectively. Human PIEZO1 expression was selective to differentiated, stratified squamous epithelia of the true vocal fold and esophagus, while PIEZO2 expression exhibited selectivity for intermediate and respiratory epithelia of the false vocal fold, ventricles, subglottis, arytenoid, and trachea. Results exhibited expression of TRPV3/4 chemoreceptors in utero, suggesting their importance during fetal/neonatal stages. TRPV3/4 and PIEZO1/2 were noted to adult murine and human laryngeal epithelium. Data indicates conservation of chemosensory receptors across species given similar regional expression in both the murine and human larynx.

Abnormal Laryngopharyngeal Sensation in Adductor Laryngeal Dystonia Compared to Healthy Controls.

Laryngeal sensory abnormality has been implicated as a component of adductor laryngeal dystonia (AdLD). The study objective was to assess laryngopharyngeal sensation in AdLD utilizing a calibrated, tactile aesthesiometer to deliver differential stimuli to lateral pyriform sinus (LPS), aryepiglottic fold (AEF), and false vocal fold (FVF). Patients with known Botox-responsive AdLD underwent sensory testing using a previously-validated methodology involving calibrated tactile stimuli (6-0, 5-0, 4.5-0, 4-0 nylon monofilaments). Laryngeal adductor reflex (LAR) and participant-rated perceptual strength of stimulI were evaluated. Responses were compared to normative controls (n=33). Two-samples, Mann-Whitney and Fisher exact tests compared mean strength ratings and LAR between AdLD and control groups. Mixed-effects logistic regression and linear models assessed association of filament size, stimulus site, age, sex, and LD status on LAR and perceptual strength rating respectively. Thirteen AdLD patients (nine women, mean age 60+/-15 years) completed testing. Average LAR response rates were higher amongst all filament sizes in AdLD versus controls at LPS (56.3% vs. 35.7%) and AEF (96.1% vs. 70.2%) with comparable rates at FVF (90.2% vs. 91.7%). AdLD had 3.3 times the odds of observed LAR compared to controls (p=0.005), but differences in subjective detection of stimuli, perceptual strength ratings, and cough/gag rates were insignificant on multivariate modeling (p > 0.05). This is the first study to objectively assess laryngopharyngeal sensation in AdLD. Findings demonstrated increased laryngopharyngeal sensation in AdLD compared to controls. The identification of increased laryngeal hypersensitivity in these patients may improve understanding of AdLD pathophysiology and identify future targets for intervention. 2 Laryngoscope, 133:2271-2278, 2023.

Hyperfunctional Laryngeal Behavior: Is It the Cause or Consequence of Vocal Fold Polyps?

To evaluate the relationship between arytenoid adduction asymmetry (AAA) and the demographic and morphological characteristics of true vocal fold (TVF) polyps and establish the cause and effect relationship between AAA and TVF polyps. Videolaryngostroboscopic findings of 163 patients with TVF polyps were retrospectively reviewed and categorized into Group 1 with AAA or Group 2 without AAA. Demographic details, clinicomorphological polyp characteristics, supraglottic phenomena, and AAA attributes were analyzed. Group 1 was younger than Group 2 (fourth vs fifth decade; P = .0066). Polyp characteristics showed no significant intergroup differences. The association between AAA and false vocal fold (FVF) adduction (65.28% vs 47.62% in Group 1 and 2 respectively; P = .0441) was significant. In relation to TVF polyp laterality, contralateral and bilateral AAA and FVF adduction respectively, was significant. AAA is a compensatory laryngeal adaptation akin to a FVF adduction muscle tension pattern. With a concomitant laryngeal pathology and high vocal demand, AAA is a consequence and not the cause for underlying laryngeal pathology which hinders glottic closure.

Beyond Laryngeal Clefts: Interarytenoid Injection Augmentation to Predict Success of Suture Augmentation in Children.

To assess the efficacy of interarytenoid injection augmentation (IAIA) and the ability of IAIA to predict response to interarytenoid suture augmentation (IASA) based on diet advancement on video fluoroscopic swallow studies (VFSS). Retrospective cohort analysis of patients with persistent pharyngeal dysphagia at a tertiary children's hospital with VFSS pre- and post-IAIA were included between March 2011 and June 2019. Median age of the 229 patients was 2.2 years (5.8 months-19 years). Interarytenoid mucosal height (IAMH) was found to be above the false vocal folds in 112 patients (53.4%) and at true vocal folds in 10 (4.9%) patients. On VFSS post-IAIA, 95 (41.5%) patients were successfully advanced in recommended diet consistency, 115 (50.2%) were stable, and 19 (8.3%) needed thicker consistency. Paired t-tests on pre- and post-operative consistency scores showed significant improvement, p-value of <0.0001, 95% confidence interval (CI; 0.50-0.85). Poisson regression found no covariates with significant association with improvement on IAIA. For IASA patients, 35/60 (58.3%) improved on post-op VFSS. Paired t-tests on pre- and post-operative consistency scores showed significant improvement, p-value of <0.0001, 95% CI (0.63-1.33). Positive predictive value for IAIA predicting response to IASA was 77% with positive likelihood ratio of 2.3. The response to IAIA versus no response to IAIA likelihood ratios were found to have a statistically significant difference (p< 0.05). Our study suggests IAIA yields objective improvement in swallow function on VFSS in nearly half of our patients and may be a reliable diagnostic tool to predict response to IASA in patients with persistent pharyngeal dysphagia with or without a laryngeal cleft. 3 Laryngoscope, 133:1749-1756, 2023.

Glottal Stop Production in Controls and Patients With Unilateral Vocal Fold Paresis/Paralysis.

The purposes of this study were to determine whether the acoustic measures from glottal stops distinguished between controls and patients with unilateral vocal fold paresis/paralysis (UVFP) at initial evaluation and posttreatment/observation, to explore the types of false vocal fold (FVF) movement during glottal stop production in UVFP, and to assess the agreement between normalization of various measures and reported voice normalization. Patients with UVFP and controls were recorded acoustically and laryngoscopically speaking two sets of five repeated /i/s, controls once and patients with UVFP initially and posttreatment/observation. Averaged intensity differences and slopes for offsets (maximum voicing intensity to minimum glottal stop intensity) and onsets (minimum glottal stop intensity to maximum voicing intensity) were measured. FVF movements were rated separately for paretic and nonparetic sides. Patients were asked to report voice normalization posttreatment/observation. Cohen's kappas were calculated for agreements between patient-reported voice normalization and normalization of Voice-Related Quality of Life (V-RQOL), translaryngeal flow, four acoustic measures of glottal stop production, and FVF movement. Significant differences (analysis of variance [ANOVA]; p < .014) were found for all acoustic measures between controls and patients with UVFP and between patients with UVFP initially and posttreatment/observation (paired t tests; p < .05). In addition, 78% of UVFP patients had no FVF movement on the paretic side initially, and 42% had bilateral dynamic FVF movement posttreatment/observation. Cohen's kappa showed moderate agreement between voice normalization and V-RQOL, slight agreement with offset measures, and fair agreement with onset measures. This study provided proof of concept for using acoustic measures of glottal stops to distinguish between controls and patients with UVFP, both initially and posttreatment/observation.

Can a flexible surgical robot be used in the pediatric population: A feasibility study

ObjectivesTransoral robotic surgery in adults confers excellent results and decreased morbidity. Application of these techniques has not yet been rigorously investigated in children. The goal of this study is to evaluate the feasibility of a flexible robotic surgical system in a pediatric population. MethodsThis was a non-randomized, non-blinded, prospective clinical trial. An Investigational Device Exemption was obtained from the FDA. Patients 8–12 years old scheduled for tonsillectomy and adenoidectomy between February and December 2019 at an academic tertiary care children's hospital were included. Exclusion criteria included pulmonary or vascular conditions posing risks for extended anesthesia, or a smaller mouth opening than the instrumentation (28 mm × 15 mm). Tonsillectomy was completed with standard monopolar cautery. After the surgery was complete, the robot was utilized for evaluation and assessment of exposure. A pediatric anesthesiologist screened patients for tolerance of additional anesthesia (up to 15 min). A flexible robotic surgical system, the MedRobotics Flex® Robotic System, was used to visualize and access the tonsillar fossa, posterior pharynx, base of tongue, epiglottis and false vocal folds. Visualization and access were graded on a five-point Likert scale. ResultsA total of ten patients, eight males and two females, with obstructive sleep apnea (OSA) or sleep disordered breathing (SDB) were recruited in 2019. One patient did not complete the study due to equipment malfunction. The average patient demographics were: age 10.1 years (8.6–11.8 years), height 142.4 cm (127–164.9 cm), weight 47.5 kg (24.4–84.5 kg), and BMI 22.6 (13.9–31.0). Study time averaged 10.3 min (5–13 min). The tonsillar fossa, base of tongue, and posterior pharynx were visualized completely and easily accessed with the robotic instruments. The epiglottis and false vocal folds were visualized and accessed in 66% and 55% of patients, respectively. There were no adverse effects. ConclusionsThis study demonstrated that a flexible robotic surgical system is feasible for use in children 8–12 years of age when performing otolaryngology - head and neck surgery procedures of the oropharynx and larynx.

Ultrasound Elastography Detects Age-Related Changes in Adult False Vocal Folds.

To investigate the feasibility of ultrasound elastography for assessing the symmetry in stiffness values and movements of both false vocal folds (FVFs). After Institutional Review Board's approval and written informed consent obtained, we measured ultrasound strain and shear wave velocity (SWV) of the bilateral FVF in vocal fold abduction and adduction in 30 participants using a linear array transducer (4-10 MHz). Twenty-eight participants met inclusion criteria as healthy subjects for analysis. Mean strain of FVF produced by FVF movement from abduction to adduction was analyzed using 2D speckle-tracking software offline. A SWV ratio ([SWVadduction - SWabduction ]/SWabduction ) was developed to test the contractibility of FVF. Statistical analysis included one-way ANOVA to test the difference in mean strain, SWV (adduction and abduction), and SWV ratio among the three age groups; linear regression to analyze correlations of stiffness and movement between the right and left FVF; and intraclass correlation coefficient (ICC) to examine intra- and interobserver reliability in performing shear wave elastography (SWE) of FVF. The 28 healthy participants were divided into 3 age groups (10 of young 20-44 years; 9 of mid-age 45-64 years; and 9 of senior ≥65 years). The SWV in FVF abduction was higher and the SWV ratio was lower in seniors compared to young participants (P < .05). Good to excellent correlation of mean strain and SWV between both FVFs (R2 > 0.89). The reliability of performing SWE of FVF was moderate to excellent. Ultrasound elastography is feasible to assess the stiffness, dynamic movement, and symmetry of adult FVF, and healthy seniors may exhibit increased FVF stiffness.