Temporary Vocal Fold Augmentation Outcomes for Refractory Chronic Cough with Concurrent Nonparalytic Glottic Insufficiency due to Vocal Fold Atrophy.

OBJECTIVE: Determine the effect of temporary vocal fold augmentation on refractory chronic cough (RCC) in patients with glottic insufficiency (GI) due to vocal fold atrophy. METHODS: Retrospective electronic chart review was conducted for patients with a diagnosis of bilateral vocal fold atrophy and RCC undergoing vocal fold augmentation with carboxymethylcellulose (CMC). Patients with vocal fold immobility were excluded, and cough must have been present for at minimum 8weeks. VHI-10, CSI, and RSI scores along with subjective overall patient report of chronic cough improvement were collected. RESULTS: A total of 28 patients underwent 30 vocal fold augmentation procedures with CMC. All had undergone extensive cough work-up and treatment trials prior to their augmentation procedure. From chart review, 13 overall subjectively reported satisfactory improvement in their cough, 5 reported partial improvement, and 7 reported no improvement in their cough. An uncertain effect on cough was documented in 5 (either patient was uncertain or no mention of cough symptom in the interval chart history note). For those subjects with both pre- and post-augmentation data, mean preaugmentation CSI: 22.08± 6.8 (n = 13); VHI-10: 13.6± 8.9 (n = 18); RSI: 22.4± 7.5 (n = 17). Mean postaugmentation CSI was 20.7± 9.2 (n = 13); VHI-10: 15.2± 8.2 (n = 18); RSI: 21.1± 5.8 (n = 17). Mean pre-post change in CSI was -1.4± 5.1 (P = 0.175, n = 13, range -10 to +6). CONCLUSIONS: Vocal fold augmentation seems to provide subjective cough improvement in some patients with concurrent GI due to vocal fold atrophy and RCC. It can be offered as a diagnostic trial, on which further augmentation may be offered, for patients with persistent cough despite prior work-up and treatment trials. Further controlled prospective studies are needed to identify factors that are predictive of successful cough improvement following vocal fold augmentation, as well as the effect of durable augmentation in those patients who had improvement with a diagnostic trial.

Comparing cadaveric and 3D-printed laryngeal models in transcutaneous injection laryngoplasty.

Background: There is increasing focus on the development of high-quality simulation models for medical education. Cadaveric models, although considered more realistic, may be difficult to obtain and costly. The advent of three-dimensional (3D) printing has offered a low-cost, reliable, and reproducible alternative. This study sought to compare the utility of 3D-printed to cadaveric models for training in transcutaneous injection laryngoplasty (TIL). Methods: A simulation course with a cross-over design was employed. Video laryngoscopes were utilized for both the 3D and cadaveric models to assess the accuracy of injection into the vocal fold. Pre-procedure and post-procedure surveys were administered to evaluate understanding and comfort level on a Likert scale of 1-10. Each model was also rated on a 1-5 Likert scale for self-efficacy, fidelity, and educational value. Results: Pre- and post-survey data were completed by 15 otolaryngology residents and medical students. Mean pre-seminar understanding and comfort level were 3.7 and 2.2, respectively, compared to 6.9 and 5.9 (p < .05) following use of the 3D model and 6.4 and 4.7 (p < .05) following use of the cadaver model. When comparing 3D and cadaveric models, no significant differences were observed regarding self-efficacy, fidelity, and educational value. Conclusion: There was a similar mean increase in understanding and comfort following use of the 3D and cadaveric models. 3D-printing can provide an excellent adjunct to, and eventually a potential replacement for hands-on cadaveric training in medical education, particularly for TIL. Level of Evidence: Level III.

Prospective Outcomes After Serial Platelet-Rich Plasma (PRP) Injection in Vocal Fold Scar and Sulcus.

OBJECTIVE: Vocal fold scar and sulcus pose significant treatment challenges with no current optimal treatment. Platelet-rich plasma (PRP), an autologous concentration of growth factors, holds promise for regenerating the superficial lamina propria. This study aims to evaluate the potential benefits of serial PRP injections on mucosal wave restoration and vocal function. METHODS: In a prospective clinical trial across two institutions, patients with vocal fold scar underwent four serial PRP injections, one month apart. Blinded independent laryngologists and expert listeners used pretreatment and one-month post-fourth injection videostroboscopy and CAPE-V assessments to evaluate mucosal wave and voice quality changes, respectively. Additionally, patient reported outcome measures (PROMs) were evaluated. RESULTS: In the study, 15 patients received 55 PRP injections without adverse effects. Eight patients (53.3%) had mild, three patients (20%) had moderate, and four patients (26.7%) had severe scar. There was an average reduction of 8.7 points in post-treatment VHI-10 scores (p = 0.007). The raters observed an improvement in post-treatment voice in 73.4% of cases, and CAPE-V scores showed a reduction of 18.8 points on average (p = 0.036). The videostroboscopic VALI ratings showed an improvement in mucosal wave rating from 2.0 to 4.0. On average, the raters perceived the post-PRP exams to be better in 56.7% of cases. CONCLUSIONS: PRP has been validated as a safe autologous option for treatment of vocal fold scar. While results for mucosal wave and voice quality varied, there was a consistent improvement in PROMs. LEVEL OF EVIDENCE: Level 3: Prospective cohort study, with blinded analysis Laryngoscope, 2024.

Update of Vocal Fold Shortening With Retrodisplacement of Anterior Commissure for Voice Feminization.

OBJECTIVES: To assess the efficacy and long-term durability of the enhanced technique of Type II Vocal Fold Shortening and Retrodisplacement of the Anterior Commissure (VFSRAC) for voice feminization compared with the preceding Type I method. METHODS: A retrospective analysis encompassed 506 patients drawn from a cohort of 1025 MtF transgender women who underwent VFSRAC between 2003 and 2021. The study period included cases from 2015 to 2021, during which the Type II update technique was implemented, involving a modification to the suture technique. Subjective and perceptual evaluations, aerodynamic and acoustic assessments, real-time pitch analysis, and videostroboscopic reviews were conducted pre- and postoperatively in the MtF transgender women cohort. Comparative statistical analyses were performed to discern differences between the earlier Type I method (2003-2014) and the more recent Type II method (2015-2021). RESULTS: The preoperative mean speech fundamental frequency (sF0) for Type II VFSRAC was 134.5 Hz. Postoperatively, the mean sF0 increased to 196.7 Hz, 212.3 Hz, and 207.5 Hz at 3 months, 6 months, and beyond 1 year, respectively, exceeding outcomes observed with the Type I method. Postoperative subjective and objective assessments indicated an augmentation in voice femininity. Acoustic and aerodynamic indices were within the normal range, and the regularity of the vocal fold mucosal wave was preserved within normal parameters. These results suggest that patients achieved a natural phonation pattern after surgery. CONCLUSIONS: The application of our updated type II VFSRAC has demonstrated feasibility and consistently yielded favorable results for individuals desiring a naturally feminine voice. LEVEL OF EVIDENCE: 3 Laryngoscope, 2024.

[Diagnosis of benign laryngeal tumors using neural network]. / Diagnostika dobrokachestvennykh novoobrazovanii gortani s primeneniem neiroseti.

The article describes our experience in developing and training an artificial neural network based on artificial intelligence algorithms for recognizing the characteristic features of benign laryngeal tumors and variants of the norm of the larynx based on the analysis of laryngoscopy pictures obtained during the examination of patients. During the preparation of data for training the neural network, a dataset was collected, labeled and loaded, consisting of 1471 images of the larynx in digital formats (jpg, bmp). Next, the neural network was trained and tested in order to recognize images of the norm and neoplasms of the larynx. The developed and trained artificial neural network demonstrated an accuracy of 86% in recognizing of benign laryngeal tumors and variants of the norm of the larynx. The proposed technology can be further used in practical healthcare to control and improve the quality of diagnosis of laryngeal pathologies.

Percutaneous Vocal Fold Lateralization in children - a case series of a Brazilian tertiary pediatric hospital (pediatric vocal fold lateralization cases in a Brazilian hospital).

OBJECTIVES: Percutaneous Vocal Fold Lateralization (PVFL) consists of external fixation with non-absorbable percutaneous suture of the vocal fold in a lateral position, under direct glottic visualization. The objective of this study is to determine the effectiveness of PVFL in a university pediatric hospital, as well as to describe the potential risks and complications of the surgery. METHODS: Retrospective cohort study, with data collected from electronic medical records. The study was approved by the Research Ethics Committee of the institution. Surgeries were performed with the modified Lichentenberg technique and data, and outcomes were analyzed. RESULTS: Six patients with Bilateral Vocal Fold Paralysis who underwent Percutaneous Vocal Fold Lateralization were evaluated. Three patients were male. The age at diagnosis ranged from 2 to 132 days (mean 10.5 days). The reason for investigating the upper airway was the presence of increased work of breathing and stridor. Five patients had a favorable clinical evolution, with spontaneous ventilation in room air and absence of stridor or ventilatory effort, without the need for tracheostomy. Surgical results in this series corroborate the findings of other similar cohorts, which showed Percutaneous Vocal Fold Lateralization as a safe and effective procedure in avoiding tracheostomy or allowing decannulation in children with Bilateral Vocal Fold Paralysis. CONCLUSIONS: PVFL seems to be a safe and effective procedure, but it has morbidity, due to immediate, and probably late, non-serious complications. Studies with a larger number of patients, with longer follow-up and using a controlled and randomized clinical design are needed to establish the role of PVFL in the treatment of BVFP in newborns and infants. LEVELS OF EVIDENCE: Level 4 (step 4).

Characterization of non-epithelial cells embedded within the vocal fold epithelial barrier.

The vocal folds vibrate to produce voice, undergoing significant stress due to contact and shearing force. The epithelium operates as the primary protective layer of the tissue against stress and vibratory damage, as well as to provide a barrier against foreign organisms and toxins. Within the vocal fold epithelium, non-epithelial cells were identified that may interrupt the epithelium and compromise the epithelial barrier's protective function. Human vocal fold samples with a variety of pathologies were compared to normal vocal folds. Analysis included the number of cells in the epithelium and epithelial thickness. Vocal fold sections from 10 human tissue samples were assessed via H&E staining and immunofluorescent co-labeling. Three cell populations (vimentin expressing, CD-45 expressing, and cells expressing both) were identified within the epithelium. Statistical analysis revealed that the abnormal samples had a significantly greater number of vimentin-positive cells/area within the epithelium compared to the normal samples. Additionally, normal tissue samples had a significantly greater epithelial depth, suggesting a more robust epithelial barrier compared to tissue with pathology. Knowledge of the function of these cells could lead to a better understanding of how the local immune environment near and within vocal fold epithelium changes in the presence of different pathologies.

Alterations in Emotional Expression Through Speech in Patients With Unilateral Vocal Fold Paralysis: A Preliminary Study.

Unilateral vocal fold paralysis (UVFP) has a known impact on patients' quality of life. One of the potentially affected domains that has not been studied yet is emotional prosody. To produce and transmit an efficient emotional prosody, several vocal parameters are modulated by the speaker, principally the fundamental frequency, the speech rate, and the voice intensity. We retrieved 300 sentences produced by 10 patients suffering from UVFP, equally in neutral, anger, and sadness. A jury of six health care voice experts was asked to hear these sentences and choose an emotion for each vocalization, between neutral, anger, and sadness. The jury mainly considered the heard sentences as being in a neutral emotion. Vocal parameters analysis of the anger and sadness sentences that were mistaken as neutral showed the absence of significant difference in their fundamental frequencies and speech rates. By being unable to modulate their vocal parameters as needed to produce emotional prosody, specifically the fundamental frequency and speech rate, patients with UVFP suffer from limitations in their capacity to produce the emotional prosody wanted, making the emotions they feel hardly transmitted to their entourage, which can explain the social barriers these patients complain of.

Effectiveness of Voice Therapy on Voice Quality and Function in Individuals with Unilateral Vocal Fold Paralysis: Systematic Review and Meta-Analysis.

BACKGROUND: Unilateral vocal fold paralysis (UVFP), characterized by immobility of one vocal fold, results from injuries of recurrent laryngeal nerves. Voice therapy is a conservative intervention aiming to address these symptoms, but standard protocols are lacking. In this study, we provided an updated review of voice therapy for UVFP over the past 3 years and analyzed the effect of voice therapy from the perspective of voice assessment recommended by the guidelines of the European Laryngological Society and the Union of the European Phoniatricians in 2023. METHODS: Following preferred reporting items for systematic reviews and meta-analyses (PRISMA) 2020 statement, we searched the databases, including PubMed, Embase, Web of Science, the Cochrane Library, and SCOPUS, from their earliest records to December 1, 2023. Quality assessment utilized Cochrane Risk of Bias and Risk Of Bias In Non-randomized Studies of Interventions tools. Data extraction encompassed study design, participant characteristics, therapy protocols, and outcome measures, including subjective and objective assessments. We performed heterogeneity analysis by calculating the I2 statistic and meta-analysis by calculating the standardized difference of means and weighted mean differences. RESULTS: Our systematic review and meta-analysis included 12 studies encompassing 459 patients. The review revealed a predominance of female participants across studies. Therapy protocols primarily included breathing control, laryngeal manipulation, and resonance training, often supplemented by home exercises. Outcome measures demonstrated significant improvements in subjective parameter: Voice Handicap Index ((standard mean difference) SMD = -1.51, P < 0.001), acoustic parameters: fundamental frequency (SMD = -0.38, P = 0.003), jitter (SMD = -0.97, P < 0.001), shimmer (SMD = -0.94, P < 0.001), and noise-to-harmonic ratio (SMD = -0.89, P < 0.001), and aerodynamic parameters: maximum phonation time (SMD = 1.29, P < 0.001), with early intervention yielding enhanced rate of complete glottal closure. DISCUSSION: Two randomized controlled trials (RCTs) involved patients aware of their allocation to the treatment group, and the remaining 10 studies were retrospective, leading to bias from deviations in the intended intervention. Subjective and aerodynamic parameter inconsistency was observed, but after excluding studies with the onset of UVFP greater than 12 months, the heterogeneity of VHI scores decreased. The funnel plot was grossly symmetrical in the publication bias test. Significant improvements were noted in subjective, acoustic, and aerodynamic outcomes after intervention. Besides, there were commonalities in protocols, such as breathing control, laryngeal manipulation, and resonance training, often supplemented by home exercises. SYSTEMATIC REVIEW REGISTRATION: This protocol was registered with the International Prospective Register of Systematic Reviews (PROSPERO) on March 28, 2024, registration number: CRD42024529750.

Comparison of the Effectiveness of Injection Laryngoplasty Using Autologous Platelet-Rich Plasma or Autologous Fat With Platelet-Rich Fibrin for the Treatment of Patients With Unilateral Vocal Fold Paralysis.

OBJECTIVES: Unilateral vocal fold paralysis (UVFP) can be idiopathic or a result of surgery, cancer, or neurological disease. The most common presentation is dysphonia, which causes problems with communication, and can lead to anxiety and depression. Injection laryngoplasty (IL) is a current means of treatment, but there have been few studies to determine the optimal material to use. Therefore, we aimed to compare the use of autologous platelet-rich plasma and autologous fat with platelet-rich fibrin for IL under local anesthesia and general anesthesia, respectively. STUDY DESIGN: A prospective randomized controlled study was conducted at the Otolaryngology-Head and Neck Surgery Department, Ramathibodi Hospital, Faculty of Medicine, Mahidol University. METHODS: Thirty-four patients with UVFP were recruited. All met the inclusion criteria and were randomized to two groups, to be treated using autologous platelet-rich plasma under local anesthesia or autologous fat with platelet-rich fibrin under general anesthesia. The primary outcome was the mean difference in the Voice Handicap Index (VHI) between the groups at 1- and 6-months post. The secondary outcomes were the mean differences in voice acoustic parameters [maximum phonation time (MPT), jitter, shimmer, and harmonic-to-noise ratio (HNR)] between the groups at these time points. RESULTS: At the measured time points, there were no significant differences in the mean VHIs (P = 0.462), MPT (P = 0.79), jitter (P = 0.234), shimmer (P = 0.863), or HNR (P = 0.096) between the groups. Few people who underwent the procedure under local anesthesia developed laryngospasm, while some of those in the fat with platelet-rich fibrin developed postoperative abdominal contusion or hematoma which resolved spontaneously. CONCLUSIONS: We have found no difference in the effectiveness of IL using autologous platelet-rich plasma under local anesthesia or autologous fat with platelet-rich fibrin performed under general anesthesia in patients with UVFP. No serious or life-threatening complications were found in both groups.

A Novel Option for Revision Medialization: Repeat Reinnervation.

Nonselective laryngeal reinnervation (NSLR) shows comparable voice results to thyroplasty after one year without permanent implants. In the rare case of a second ipsilateral vocal fold paralysis after NSLR, we present the first recorded revision NSLR. Case report. A 51 year old woman with a history of right NSLR in 2017 for vocal fold paralysis after an anterior cervical diskectomy and fusion (ACDF) presented for re-evaluation prior to a revision of her ACDF. Ipsilateral revision was recommended to reduce the risk of bilateral vocal fold paralysis. Post-operatively, she was noted to have vocal fold immobility. Her maximum phonation time at that time was 9 s. Her voice was moderately breathy and moderately asthenic. Fundamental frequency (F0) was 211 Hz. Jitter was 2.868%, and shimmer 14.429%. Noise to harmonic ratio was 0.366. Cepstral peak prominence was 2.689. After being offered thyroplasty or revision reinnervation, she opted for revision reinnervation due to a strong preference for her reinnervated voice. She underwent a revision cross-neck NSLR with a commercial nerve graft in September 2022. One year later, her MPT was found to be 7.6 s, with mild breathiness and asthenia. F0 was 190 Hz. Jitter decreased to 2.42%, shimmer to 6.478%, and NHR to 0.165. Cepstral peak prominence increased to 4.427. VHI decreased from 35 pre-operatively to 7 post-operatively. We present the first case of a revision NSLR. Notable improvement has been found in objective voice measures and patient-reported outcomes post-operatively, demonstrating feasibility in similar patients. Laryngoscope, 2024.

Stimulated Vocal Fold Immobility After Vagal Nerve Stimulator Placement: A Case Series.

INTRODUCTION: Vagal nerve stimulator (VNS) implantation is a vital therapy for epilepsy refractory to other treatments; however, it is associated with a very high rate of voice changes. Relatively few of these patients are evaluated for vocal fold motion impairments. In this series, we evaluate 5 such patients with a novel phenotype of forced abduction with VNS stimulation. METHODS: Retrospective case series. RESULTS: Five patients with a VNS implant who underwent operative direct or in-office rigid laryngoscopy and had vocal fold motion impairment associated with VNS activation are included. All 5 patients had vocal fold mobility with VNS off and a fixed with activation. All patients exhibited vocal fold abduction with VNS activation. Patient 2 has since undergone laryngeal reinnervation, which helped her intermittent dysphonia but left a small glottic gap. A type 1 thyroplasty corrected this gap and improved her voice further. Patient 3 has undergone laryngeal reinnervation for which early results show improvement in perceptual and patient reported outcomes. Patients 4 and 5 have both undergone laryngeal reinnervation with improvement in voice. CONCLUSION: Previous reported cases of stimulated immobility associated with VNS use describe only adduction of the vocal fold. This series expands the previous work showing the VNS activation can also cause stimulated immobility in an abducted position, for which reinnervation and other medialization procedures offer promising treatment.

Radiofrequency Versus CO2 Laser in Posterior Cordotomy for Managing Bilateral Abductor Vocal Fold Immobility.

PURPOSE: This study aimed to assess the outcomes of posterior cordotomy in cases with bilateral abductor vocal fold immobility (BAVFI), either by radiofrequency or CO2 laser. METHODS: This prospective comparative randomized study included 80 patients with BAVFI of different etiologies. They were divided randomly into two groups. Group A included 44 patients for whom radiofrequency was used for posterior cordotomy, while the other group (group B) included 36 patients managed by CO2 laser-assisted posterior cordotomy. RESULTS: The postoperative respiratory chink improved significantly in both groups, with a significant improvement in the dyspnea, especially in group B. The postoperative voice handicapped VHI-10 scores showed significant deterioration in both groups. CONCLUSIONS: CO2 laser and radiofrequency-assisted posterior cordotomy were effective and safe for managing cases with BAVFI. Moreover, the CO2 laser has the upper hand regarding breathing and exercise tolerance outcomes, significantly impacting the quality of life.

Scaffold-Forming Collagen and Motor-Endplate Expressing Muscle Cells for Porcine Laryngoplasty.

OBJECTIVE: Vocal fold paralysis impairs quality of life, and no curative injectable therapy exists. We evaluated injection of a novel in situ polymerizing (scaffold-forming) collagen in the presence and absence of muscle-derived motor-endplate expressing cells (MEEs) to promote medialization and recurrent laryngeal nerve (RLN) regeneration in a porcine model of unilateral vocal fold paralysis. METHODS: Twelve Yucatan minipigs underwent right RLN transection. Autologous muscle progenitor cells were isolated from muscle biopsies, differentiated, and induced to MEEs. Three weeks after RLN injury, animals received injections of collagen, collagen containing MEEs, or saline into the paralyzed right vocal fold. Stimulated laryngeal electromyography and acoustic vocalization were used for function assessments. Larynges were harvested and underwent histologic, gene expression, and further quantitative analyses. RESULTS: Injections were well-tolerated, with the collagen scaffold showing immunotolerance and collagen-encapsulated MEEs remaining viable. Collagen-treated paralyzed vocal folds showed increased laryngeal adductor muscle volumes relative to that of the uninjured side, with those receiving MEEs and collagen showing the highest volumes. Muscles injected with MEEs and collagen demonstrated increased expression of select neurotrophic (BDNF and NTN1), motor-endplate (DOK7, CHRNA1, and MUSK), and myogenic (MYOG and MYOD) related genes relative to saline controls. CONCLUSION: In a porcine model of unilateral vocal fold paralysis, injection of in situ polymerizing collagen in the absence and presence of MEEs enhanced laryngeal adductor muscle volume, modulated expression of neurotrophic and myogenic factors, and avoided adverse material-mediated immune responses. Further study is needed to determine long-term functional outcomes with this novel therapeutic approach. LEVEL OF EVIDENCE: NA Laryngoscope, 2024.

Logical Fallacies in Missed Diagnosis of Stridorous Patients: A Case Report.

Tracheal stenosis and paradoxical vocal fold motion are both common laryngological diagnoses that can present with similar symptoms of dyspnea. Co-morbid psychiatric issues can complicate diagnostic accuracy and lead to logical fallacies in the attribution of symptom etiology. We present a case of a 38-year-old female who presented repeatedly to the emergency department with respiratory distress, inspiratory stridor, wheezing, and anxiety. On examination, she had stridor that appeared to correlate with episodes of elevated anxiety and bedside laryngoscopy which showed intermittent paradoxical vocal fold motion. A computed tomography scan showed 40% narrowing of the distal tracheal lumen, but symptoms were felt to be inconsistent and out of proportion to stenosis. She was seen several more times in the ED and eventually followed up in the laryngology clinic, where she had a tracheoscopy showing Cotton Meyer grade III stenosis. This unique case highlights the logical fallacies that may lead to misdiagnosis when evaluating stridorous patients with comorbid personality and anxiety disorders.

Explore the Pattern of Biomechanical Alterations in Vocal Fold Scar and Its Objective Quantitative Assessment Method.

OBJECTIVES: This research aims to discern the evolving nature of the biomechanical properties of vocal fold scarring by calculating Young's modulus for the vocal fold cover layer, the body layer, and the structure as a whole. The study also investigates the potential of diffusion tensor imaging (DTI) for determining these biomechanical characteristics quantitatively. METHODS: A total of six adult female Beagles were divided into two groups (A and B groups) for the creation of unilateral vocal fold scar models, each group containing three subjects. Five months postmodel creation, larynxes were excised and placed within a 9.4T BioSpec MRI system (Bruker, Germany) for scanning. Subsequently, the vocal folds were segregated from the larynx. In A group of Beagles, the vocal fold cover layer and body layers were separated, whereas in B group they remained intact. All samples were then subjected to cyclic tensile testing using an Instron MicroTester 5948, with Young's modulus computed for the vocal fold cover layer and body layers in the A group and for the intact vocal fold in the B group. Differences in the overall Young's modulus between the vocal fold scarred side and the healthy side were analyzed, and a Pearson correlation analysis was performed between DTI parameters and the outcomes of the stress-strain experiments. RESULTS: A statistically significant discrepancy in the overall Young's modulus was identified between the scar and healthy sides of the vocal fold (P = 0.0401). The Young's modulus also displayed a significant difference between the scar and healthy sides of the vocal fold cover layer (P = 0.0241). No meaningful divergence was observed in the elastic modulus between the scar and healthy sides of the vocal fold body layer (P > 0.05). Postseparation, Young's modulus for both the cover and body layers of the scarred vocal fold were less than that of the same layers on the healthy side. However, Young's modulus of the entirety of the vocal fold on the scar side was greater than that of the whole vocal fold on the healthy side. The fractional anisotropy (FA) of the vocal fold cover layer had a significant correlation with the elastic modulus (r = 0.812, P = 0.050), as did the Tensor trace (r = -0.821, P = 0.045). The FA of the vocal fold body layer showed no significant correlation with the elastic modulus (r = -0.725, P = 0.103), while the Tensor trace demonstrated a significant correlation (r = 0.911, P = 0.012). CONCLUSIONS: Biomechanical alterations in vocal fold scars demonstrate a closer association with adhesion bands, thus emphasizing the importance of adhesion band loosening for the restoration of vibratory function within vocal fold scarring. DTI emerges as a potent noninvasive quantitative instrument for assessing these biomechanical changes, as well as for quantitatively gauging the severity of vocal fold scarring.

Acoustic Character Governing Variation in Normal, Benign, and Malignant Voices.

INTRODUCTION: Benign and malignant vocal fold lesions (VFLs) are growths that occur on the vocal folds. However, the treatments for these two types of lesions differ significantly. Therefore, it is imperative to use a multidisciplinary approach to properly recognize suspicious lesions. This study aimed to determine the important acoustic characteristics specific to benign and malignant VFLs. METHODS: The acoustic model of voice quality was utilized to measure various acoustic parameters in 157 participants, including individuals with normal, benign, and malignant conditions. The study comprised 62 female and 95 male participants (43 ± 10 years). Voice samples were collected at the Shanghai Eye, Ear, Nose, and Throat Hospital of Fudan University between May 2020 and July 2021. The acoustic variables of the participants were analyzed using Principal Component Analysis (PCA) to present important acoustic characteristics that are specific to normal vocal folds, benign VFLs, and malignant VFLs. The similarities and differences in acoustic factors were also studied for benign conditions including Reinke's edema, polyps, cysts, and leukoplakia. RESULTS: Using the PCA method, the components that accounted for the variation in the data were identified, highlighting acoustic characteristics in the normal, benign, and malignant groups. The analysis indicated that coefficients of variation in root mean square energy were observed solely within the normal group. Coefficients of variation in pitch (F0) were found to be significant only in benign voices, while higher formant frequencies and their variability were identified as contributors to the acoustic variance within the malignant group. The presence of formant dispersion (FD) as a weighted factor in PCA was exclusively noted in individuals with Reinke's edema. The amplitude ratio between subharmonics and harmonics (SHR) and its coefficients of variation were evident exclusively in the polyps group. In the case of voices with cysts, both pitch (F0) and coefficients of variation for FD were observed to contribute to variations. Additionally, higher formant frequencies and their coefficients of variation played a role in the acoustic variance among voices of patients with leukoplakia. CONCLUSION: Experimental evidence demonstrates the utility of the PCA method in the identification of vibrational alterations in the acoustic characteristics of voice affected by lesions. Furthermore, the PCA analysis has highlighted underlying acoustic differences between various conditions such as Reinke's edema, polyps, cysts, and leukoplakia. These findings can be used in the future to develop an automated malignant voice analysis algorithm, which will facilitate timely intervention and management of vocal fold conditions.

Quality of Life in Recurrent Respiratory Papillomatosis Patients after Vocal Fold Surgery: An In-Depth Exploration.

INTRODUCTION: This study explores the quality of life among patients with recurrent respiratory papillomatosis (RRP) after vocal fold surgery as measured by the outcome scores of the Voice Handicap Index (VHI) and the Distress Thermometer and Problem List in Patients with Recurrent Respiratory Papillomatosis (DT&PL). Differences in quality of life were explored within the independent variables age, surgical frequency, weeks since last vocal fold operation, gender, HPV type, surgical location, vaccination with Gardasil©, and a patient's request to speak with a speech-language pathologist. METHODS: A single-center, observational cohort study was conducted using VHI and DT&PL scores and demographic and clinical data obtained from patient files. Inclusion criteria were a confirmed HPV type, age 18 years or older, the ability to fill in both questionnaires in Dutch, and having undergone at least one surgical procedure to remove laryngeal papilloma. Relationships of the independent variables with VHI and Distress Thermometer (DT) scores were explored using univariable and multivariable regressions and linear regression models. RESULTS: Of 271 RRP patients, 100 met the inclusion criteria and responded to requests to fill in both questionnaires with a minimum of 12 weeks after their last operation. Our study showed a statistically significant negative relationship between age and VHI scores (p = 0.02) in the univariable, and multiple linear regressions (p = 0.01), indicating that patients experienced fewer self-perceived functional voice disabilities with each increase in age. A parallel negative relationship is seen between the variables age (p = 0.03) and DT scores. Our results showed a statistically significant positive relationship between the number of vocal fold surgeries and DT scores (p = 0.03). CONCLUSION: The results of this study show a significant relationship between age, surgical frequency, and quality of life in patients with RRP. Older patients have lower Voice Handicap Index (VHI) and Distress Thermometer (DT) scores, indicating fewer self-perceived voice and disease-related quality of life problems. Conversely, a rise in surgical frequency is significantly associated with higher DT scores, reflecting greater disease-related distress.

Virtual Reality-Enhanced Assessment of the Anterior Glottic Angle Using Cadaveric Models: A Proof-of-Concept Study.

OBJECTIVES: Vocal fold paralysis (VFP) is a complex disorder that affects voice, speech, swallowing, and overall quality of life. Current evaluation methods for determining the position of paralyzed vocal folds lack the objectivity required for personalized interventions and research on innovative treatments for VFP. This study was designed to validate the accuracy and reproducibility of a virtual reality (VR)-based platform to measure the anterior glottic angle (AGA), a critical component in determining the position of a paralyzed vocal fold. STUDY DESIGN: Retrospective. METHODS: A retrospective analysis of computed tomography (CT) scans of 39 adult patients was conducted to measure the AGA shortly after death. Two measurement methods were used: 2-dimensional (2D)-CT for direct measurements on 2D images and a 3-dimensional (3D)-VR method utilizing a dedicated platform to create a 3D VR model of the larynx. The AGA measurements conducted by two senior otolaryngologists using the 3D-VR method were compared to the 2D-CT measurements made by one of these same otolaryngologists. RESULTS: The mean AGA measured by the 3D-VR method was found to be 32.936 ± 6.486° (n = 39), and the measurements were highly correlated (r = 0.9670, P < 0.0001). By contrast, the 2D-CT method without VR yielded a significantly lower mean angle of 23.754° (n = 35) with a higher standard deviation of 10.365°. The 3D-VR method demonstrated excellent reliability for AGA measurements (intraclass correlation coefficient of 0.954). CONCLUSION: The findings underscore the potential value of using a VR-based platform to improve reproducibility and reduce the variability in measurements of AGA in cases of VFP.

Precision-Targeted Injection Laryngoplasty and Longitudinal Biomaterial Effects Evaluation Using High-resolution Ultrasonography in a Rat Model.

OBJECTIVE: Current laryngeal injection models rely on the transoral route and are suboptimal due to limited view, narrowed working space, and the need to sacrifice animals for investigation of the injectables. In the present study, a novel surgical model for laryngeal intervention therapy utilizing an ultra-high frequency ultrasound imaging system was proposed. Based on this system, we developed a systemic evaluation approach, from guidance of the injection process, documentation of the injection site of the material, to in vivo longitudinal follow-up on the augmentation and medialization effect by analyzing the ultrasonography data. STUDY DESIGN: In vivo animal study. SETTING: Academic institution. METHODS: Injection laryngoplasty with hyaluronic acid under ultrasonography guidance was performed on Sprague-Dawley rats one week after induced unilateral vocal paralysis. Ultrasonography was performed at preinjection, immediately postinjection, on Day 2, Day 7 and then weekly for 4 weeks to obtain measurements, including the glottic area, angle between bilateral folds, and vocal fold width ratio. Laryngoscopic and histologic studies were also performed. RESULTS: Unilateral injections to the paralyzed fold were successfully performed as demonstrated by ultrasonographic, laryngoscopic, and histologic studies. The width ratio was significantly increased after injection for 4 weeks, while the glottic airway area was unchanged. CONCLUSION: Here, a novel surgical model for laryngeal injection utilizing ultrasonography in rats was established. In addition to providing visual guidance for precise localization of the injection, robust documentation of the treatment effect was also demonstrated. This methodology could be beneficial for screening therapeutic agents for treatment of glottic insufficiency.