Aspiration Prevention Surgery: Clinical Factors Associated With Improvements in Oral Status Intake and Suction Frequency.

OBJECTIVE: In recent years, the use of aspiration prevention surgery (APS) for the treatment of severe dysphagia has been on the rise. However, relevant clinical studies have included small samples, and the frequency of, and risk factors for postoperative complications have not been clarified. We investigated the clinical features of patients undergoing APS and whether oral-intake status and suction frequency could be reduced. STUDY DESIGN: A case series. SETTING: Single-institution academic center. METHODS: We retrospectively evaluated medical charts generated from 2010 to 2021. The clinical characteristics of patients undergoing APS, changes in the oral-intake status (Functional Oral Intake Scale, FOIS), suction frequency before and after surgery, risk factors for postoperative complications, and factors contributing to improvements in postoperative oral-intake status were retrieved. RESULTS: We included the data of 100 patients (median age: 65 years, 72 men). Amyotrophic lateral sclerosis was the most common primary disease (28%), and glottis closure was the most common APS (69%). Postoperatively, 78% of patients showed improvements in the FOIS score, and suction frequency decreased in 85% of cases. Postoperative complications were observed in 10 patients (10%), wound infection in 6, and bleeding in 4; all improved. Higher preoperative FOIS scores were significantly associated with postoperative complications (p = 0.02). CONCLUSION: APS contributed to improving the FOIS score and helped reduce the suction frequency in most cases. APS can be performed safely with proper perioperative management, even in patients with poor preoperative general conditions and nutritional status.

Validity of intraoperative voice monitoring undergoing type 2 thyroplasty with titanium bridges for adductor spasmodic dysphonia.

Objectives: The success of type 2 thyroplasty (TP2) for adductor spasmodic dysphonia (AdSD) depends on the selection of optimally sized titanium bridges, which requires accurate assessment of intraoperative vocal changes. While this procedure has traditionally been performed according to the laryngologist's experience, the most appropriate method for voice monitoring and selection of titanium bridge size remains to be determined. This study aimed to investigate evaluation parameters useful for voice monitoring, as these may allow less experienced surgeons to perform TP2 properly. Methods: In this prospective study, voice monitoring was performed in 18 patients with AdSD patients undergoing TP2. Evaluations were performed preoperatively, intraoperatively, 13 weeks postoperatively, and 52 weeks postoperatively using GRBAS (grade, roughness, breathiness, asthenia, and strain), as well as perceptual judgment and acoustic analyses. Results: Preoperative and intraoperative assessments of the G, R, B, and S parameters, perceptual judgment, and harmonic-to-noise ratio (HNR) were in moderate or better agreement. Intraoperative and 13- or 52-week postoperative measurements of the R, B, and G parameters and strangulation, tremor, and HNR were also in high agreement. When two different sizes of titanium bridges were compared (unselected vs. selected), ratings for G, R, S, strangulation, tremor, jitter, shimmer, HNR, standard deviation of F0, and degree of voice breaks were better for the selected width than the unselected width. Conclusion: The candidate items for intraoperative voice monitoring during TP2 for AdSD are G, R, strangulation, tremor, and HNR. The use of these items may help to ensure successful TP2 and contribute to the advancement of laryngeal framework surgery. Level of evidence: Level 4.

Sex-and Age-Based Etiological Analysis of 2901 Patients With Dysphonia in a Japanese Tertiary Medical Institute.

OBJECTIVES: Societal aging is a grave concern in Japan, and its impact on voice clinics has not been investigated. This study aimed to clarify recent demographic features of geriatric dysphonia at a tertiary medical institute in Japan. STUDY DESIGN: Retrospective study. METHODS: The medical records of 2901 patients newly referred to the Voice Outpatient Clinic of the University of Tokyo Hospital between 2003 and 2020 were analyzed for age, sex, and etiology. RESULTS: The mean ± standard deviation age of all patients was 53.2 ± 20.7 (median, 58; range, 0-95) years. The aging rate (ratio of patients aged ≥65 years) increased continuously during the study period, and the recent aging rate was the highest in the world (43%). However, its rate of increase has slowed over the past 10 years. The etiologies of dysphonia associated with the largest number of older patients were vocal fold immobility (32%), vocal fold atrophy (23%), and benign vocal fold lesions (11%). The highest aging rate was detected in patients with laryngeal cancer/leukoplakia, vocal tremor, vocal fold atrophy, sulcus vocalis, and vocal fold immobility. CONCLUSIONS: Societal aging substantially increased the aging rate of patients with dysphonia in a Japanese voice clinic. The incidence of vocal fold immobility and atrophy is expected to continue to increase, whereas that of benign vocal fold lesions is expected to decrease.

Aspiration Prevention Surgery under Local Anesthesia for Palliative Care in Patients with Head and Neck Cancer: A Report of Two Cases.

Aspiration prevention (AP) surgery may improve the quality of life (QOL) of patients with severe dysphagia. However, not all patients can endure this type of surgery under general anesthesia because of their poor status. Herein, we describe the cases of 2 patients with head and neck cancer (HNC) who underwent AP surgery for palliative care. Although both patients had tracheostomy due to severe dysphagia and respiratory impairment and frequently needed suction, they were successfully managed with AP surgery under local anesthesia. A tracheostoma was reshaped to be sufficiently large for an airway to be secured without a cannula. Their respiratory failure gradually improved, and suction frequency markedly decreased after surgery; thus, they could receive medical treatment at home. When patients with HNC under palliative care have a tracheal cannula and cannot vocalize, AP surgery under local anesthesia is an option to improve their QOL.

Heightened risk of early vocal fold motion impairment onset and dysphagia in the parkinsonian variant of multiple system atrophy: a comparative study.

OBJECTIVE: We compared differences in frequency and timing of onset of the following clinical events between the cerebellar and parkinsonian variants of multiple system atrophy (MSA-C and MSA-P, respectively): type of operation including tracheostomy and/or aspiration prevention surgery, vocal fold motion impairment (VFMI), sleep apnea (SA), introduction of mechanical ventilation (MV), and dysphagia. The risks of these events cooccurring with either MSA-C or MSA-P were compared. METHODS: We retrospectively assessed clinical outcomes only of patients with MSA who presented at the Department of Otolaryngology of the University of Tokyo Hospital between 2008 and 2018. The proportion and timing of onset events between MSA-C and MSA-P and risks of onset were compared using chi-square tests and Cox proportional hazard models adjusted for age, sex, and disease severity, respectively. RESULTS: We identified 113 patients (median age: 60 years, 72 men [64%]). The frequency and timing of VFMI, SA, MV, dysphagia, and surgeries were 55 patients (49%) and 76 (95% CI 61-91) months after MSA onset, 85 (75%) and 41 (32-50), 36 (32%) and 100 (73-127), 77 (68%) and 43 (36-50), and 25 (22%) and 102 (84-120), respectively. Twenty-seven patients (24%) had MSA-P and higher risk of VFMI (p < .001), SA (p = .030), and dysphagia (p = .017) than did patients with MSA-C. CONCLUSION: While MSA-P is less common, it may involve heightened risk of VFMI and dysphagia early onset. Thus, careful follow-up for VFMI, SA, and dysphagia may be needed for these patients. CRITERIA FOR RATING DIAGNOSTIC ACCURACY STUDIES: Class II.

A new training method for velopharyngeal dysfunction: Self-inhalation for hypernasality.

OBJECTIVE: There are various methods to treat velopharyngeal dysfunction including　surgery and rehabilitation therapy. Even if a rehabilitation program is effective, the evaluation of its efficacy remains subjective. In this paper, we propose a new method of rehabilitation training for velopharyngeal dysfunction focusing on the objective peak inspiratory flow (PIF) rate. METHODS: Four patients, who were diagnosed with velopharyngeal dysfunction without cleft palate at ENT clinic of the National Hospital Organization, Tokyo Medical Center, participated in this study. All patients underwent our original rehabilitation program for velopharyngeal dysfunction, a method using the In-Check Dial, Turbohaler model. As a self-training rehabilitation program, we asked them to inhale forcefully 10 times daily at home using the In-Check Dial to increase the value of PIF rate for 3 months. We measured the patients' PIF rates with the In-Check Dial at the ENT clinic at the initial visit and after the 3-month training. RESULTS: The PIF rates of the four patients without nasal clips were higher than the rates with nasal clips at the initial visit. After the training, PIF rate without a nasal clip of all patients increased than the rate at the initial visit, which represented significant difference (P < 0.05). Also, after 3 months, PIF rate without a nasal clip was higher or equal than the rates with a nasal clip at the initial visit except one case. Naso-pharyngo-laryngeal fiberscopy did not detect salivary pooling around larynx and mirror fogging test did not show nasal escape in the three of four patients after 3 months of training. All reported improvement in dysphagia and dysarthria. CONCLUSION: This new method can be used not only to evaluate velopharyngeal function but also as an effective self-training treatment.

Investigation of the Safety of Injection Laryngoplasty under Antithrombotic Therapy.

BACKGROUND: Glottic insufficiency negatively affects phonation and swallowing function. Injection laryngoplasty is a convenient and minimally invasive treatment for glottic insufficiency. This study assessed whether injection laryngoplasty is safe under continued administration of antithrombotic drugs, and aimed to establish measurable laboratory values under which such a procedure can be safely performed. METHOD: This retrospective medical record review covered the period from November 2012 to June 2018. We examined 17 patients who underwent injection laryngoplasty (47 injections) under continued administration of antithrombotic drugs at the University of Tokyo Hospital. We analyzed clinical and demographic profiles, complications, and blood test values. Statistical analyses were performed regarding the risks of complications due to injection side, route of administration, and number of antithrombotic drugs. RESULTS: No patients exhibited airway narrowing or dyspnea; however, bleeding after injection laryngoplasty was observed in 3 patients. All patients exhibited values within the optimal treatment range. There were no significant differences regarding the risks of complications due to injection side, route of administration, or number of antithrombotic drugs. CONCLUSIONS: When the platelet count, prothrombin time-international normalized ratio, and activated partial thromboplastin time were within the optimal range prior to treatment, injection laryngoplasty could safely be performed, regardless of the administration of antithrombotic drugs.

Acute inflammatory response to contrast agent aspiration and its mechanisms in the rat lung.

OBJECTIVES/HYPOTHESIS: Contrast agent (CA) aspiration is an established complication of upper gastrointestinal and videofluoroscopic swallow studies. The underlying molecular biological mechanisms of acute response to CA aspiration in the respiratory organs remain unclear. The aims of this study were to elucidate the histological and biological influences of three kinds of CAs on the lung and to clarify the differences in acute responses. STUDY DESIGN: Animal model. METHODS: Eight-week-old male Sprague Dawley rats were divided into five groups (n = 6 in each group). Three groups underwent tracheal instillation of one of three different CAs: barium (Ba) sulfate, nonionic contrast agents (NICAs), and ionic contrast agents (ICAs). A control group was instilled with saline and a sham group was instilled with air. All animals were euthanized on day 2 after treatment and histological and gene analysis was performed. RESULTS: No animal died after CA or control/sham aspiration. Ba caused severe histopathologic changes and more prominent inflammatory cell infiltration in the lungs compared with the two other iodinated contrast agents. Increases in expressions of inflammatory cytokines (tumor necrosis factor [Tnf], interleukin-1ß [Il1b], and interferon-γ [Ifng]) were observed in Ba aspiration rats, and upregulation of Il1b was seen in ICA aspiration rats. NICA did not cause obvious histologic changes or expressions of inflammatory cytokines and fibrosis-related genes in the lungs. CONCLUSIONS: Ba caused significantly more acute lung inflammation in a rodent model than did ioinic and nonionic iodinated CAs. Nonionic contrast did not cause any discernible inflammatory response in the lungs, suggesting that it may be the safest contrast for videofluoroscopic swallow studies. LEVEL OF EVIDENCE: NA Laryngoscope, 129:1533-1538, 2019.

Vocal Hygiene Education Program Reduces Surgical Interventions for Benign Vocal Fold Lesions: A Randomized Controlled Trial.

OBJECTIVES/HYPOTHESIS: Vocal fold polyps and nodules are common benign laryngeal lesions. Currently, the Japanese health insurance system covers surgical interventions. However, the establishment of more cost-effective conservative methods is required, because healthcare costs are viewed as a major concern, and the government and taxpayers are demanding more economical, effective treatments. In this situation, more suitable vocal hygiene education may be important for the success of cost-effective conservative treatment. In this study, we developed a novel reinforced vocal hygiene education program and compared the results of this program with those of previous methods of teaching vocal hygiene. STUDY DESIGN: Multicenter randomized controlled trial. METHODS: Patients who visited a National Hospital Organization (NHO) hospital for the surgical indication of hoarseness were included in the study. Before undergoing surgery, 200 patients with benign vocal fold lesions (vocal fold polyps/nodules) were enrolled and randomly allocated to the NHO-style vocal hygiene educational program (intervention group) or control education program (control group). Two months after enrollment, the patients in both groups underwent laryngeal fiberscopic examinations to determine whether the benign lesions had resolved or whether surgery was indicated for the vocal fold polyps/nodules. RESULTS: After 2 months, in the intervention group, the proportion of lesion resolution (61.3%) was significantly greater than that in the control group (26.3%) (P < .001, Fisher exact test). CONCLUSIONS: Our results clearly indicate that the quality and features of the education program could affect the outcome of the intervention. We found that a reinforced vocal hygiene education program increased the rate of the resolution of benign vocal fold polyps and nodules in a multicenter randomized clinical trial. LEVEL OF EVIDENCE: 1b Laryngoscope, 2593-2599, 2018.

Management of laryngeal cleft in mechanically ventilated children with severe comorbidities.

Laryngeal clefts are rare congenital malformations of the posterior part of the larynx. The severities are correlated with the downward extension of the cleft and can involve numerous clinical symptoms including dysphagia and respiratory distress. As significant comorbidities may be present, individual treatments depend on the child's general condition and type of cleft involved. Herein, we describe two cases of children with laryngeal clefts and severe comorbidities requiring mechanical ventilation. One child with type III laryngeal cleft was successfully managed with the lateral pharyngotomy approach. The other child with type II laryngeal cleft has not been able to undergo cleft-closure surgery because of severe general conditions, therefore has continued training for feeding and swallowing.

Unilateral vocal fold adductor paralysis after tracheal intubation.

Vocal fold immobility is a relatively rare complication that can occur after tracheal intubation. Differential diagnoses include a rare clinical entity called unilateral vocal fold adductor paralysis in which only branches entering the thyroarytenoid and lateral cricoarytenoid muscles of the recurrent laryngeal nerve become paralyzed. Computed tomography and laryngeal electromyography are required to distinguish this condition from others such as cricoarytenoid dislocation/subluxation. Here, we describe two patients who developed vocal fold adductor paralysis after intubation. Patient 1 was a 56-year-old man who underwent living-donor liver transplantation and was extubated on day 7 after surgery. Patient 2 was a 52-year-old man who received life support measures including intubation due to ventricular fibrillation, and was extubated two days later. Both were hoarse soon after extubation. Endoscopic laryngeal examination revealed normal abduction and insufficient adduction of paralyzed vocal folds. Computed tomography ruled out cricoarytenoid dislocation/subluxation and laryngeal electromyography confirmed unilateral vocal fold adductor paralysis. Laryngologists should consider this rare pathogenesis.

Relationship Between Laryngeal Sensory Deficits, Aspiration, and Pneumonia in Patients with Dysphagia.

The laryngeal adductor reflex (LAR) is an airway protective reflex that manifests as a brief vocal fold closure in response to laryngeal stimulation. This study examined if the absence of the LAR in response to touch delivered by a laryngoscope is associated with penetration/aspiration or pneumonia in patients with dysphagia. Inpatients at a teaching hospital with clinical symptoms of dysphagia were recruited upon referral to the otolaryngology clinic for a swallowing evaluation. Otolaryngologists observed the status of secretions and touched each arytenoid with the tip of the laryngoscope. The patients were then asked to swallow 3-5 mL grape gelatin and 3-5 mL colored water. All procedures were video-recorded. Two independent raters noted absence/presence of the LAR and penetration/aspiration of pharyngeal secretions, gelatin, and water on the recorded videos. A diagnosis of pneumonia during the patient's entire hospital stay was determined by a review of the hospital's medical records. Statistical analyses were performed using Fisher's exact test. Sixty-one patients were included. Twenty-one patients (34.5%) did not exhibit the LAR. No association was found between the absent LAR and penetration or aspiration. There was, however, a significant association between an absence of the LAR and pneumonia development. Patients with an absent LAR had 6.8 times the odds of developing pneumonia as compared to those with a present LAR (OR 6.75; 95% CI 1.76-25.96; p < 0.01). Using the LAR as a marker of laryngeal sensory function appears to be valuable for identifying patients at high risk of pneumonia.

Bilateral vocal cord immobility resulting from cytomegalovirus pharyngitis: A case report.

Human cytomegalovirus (CMV) is an infectious herpes virus present in approximately 50% of the world's population. Pharyngitis is an uncommon manifestation of CMV infection, and vocal cord immobility (VCI) following CMV pharyngitis is quite rare. An 83-year-old man with well-controlled diabetes mellitus and hypertension was admitted due to dyspnea, odynophagia, and dysphagia. Laryngeal fiberscopy revealed bilateral vocal cords almost fixed at the median position, with mucosal redness, swelling, and edema at the hypopharyngeal area. The airway was so narrowed that an emergency tracheostomy was performed to secure an airway. VCI resulting from a malignant tumor was suspected at first, but repeated pathological examinations revealed CMV infection in the pharyngeal mucosa. Despite intravenous ganciclovir treatment (5 mg/kg), the patient's bilateral VCI improved only slightly. Laryngeal electromyography was used to investigate the causes of VCI, and revealed vocal fold paralysis on the left side and cricoarytenoid joint fixation on the right side. This case highlights the importance of considering CMV infection in the differential diagnosis of patients with pharyngitis and VCI. To the best of our knowledge, this is the first case report describing the etiology of VCI following CMV pharyngitis using laryngeal electromyography.

Variability of the Pressure Measurements Exerted by the Tip of Laryngoscope During Laryngeal Sensory Testing: A Clinical Demonstration.

PURPOSE: Clinicians often test laryngeal sensation by touching the laryngeal mucosa with the tip of a flexible laryngoscope. However, the pressure applied to the larynx by using this touch method is unknown, and the expected responses elicited by this method are uncertain. The variability in pressure delivered by clinicians using the touch method was investigated, and the subject responses to the touches were also reported. METHODS: A fiberoptic pressure sensor passed through the working channel of a laryngoscope, with its tip positioned at the distal port of the channel. Two examiners each tested 8 healthy adults. Each examiner touched the mucosa covering the left arytenoid 3 times. The sensor recorded the pressure exerted by each touch. An investigator noted subject responses to the touches. From the recorded videos, the absence or presence of the laryngeal adductor reflex in response to touch was judged. RESULTS: Pressure values obtained for 46 of the 48 possible samples ranged from 17.9 mmHg to the measurement ceiling of 350.0 mmHg. The most frequently observed response was positive subject report followed by the laryngeal adductor reflex. CONCLUSION: Pressure applied to the larynx by using the touch method was highly variable, indicating potential diagnostic inaccuracy in determining laryngeal sensory function.

Laryngeal mucus hypersecretion is exacerbated after smoking cessation and ameliorated by glucocorticoid administration.

INTRODUCTION: The mechanisms underlying the effects of cigarette smoke and smoking cessation on respiratory secretion, especially in the larynx, remain unclear. OBJECTIVES: The aims of this study were to determine the effects of cigarette smoke and smoking cessation on laryngeal mucus secretion and inflammation, and to investigate the effects of glucocorticoid administration. METHODS: We administered cigarette smoke solution (CSS) to eight-week-old male Sprague Dawley rats for four weeks, then examined laryngeal mucus secretion and inflammatory cytokine expression on days 1, 28 and 90 after smoking cessation. We also investigated the effects of the glucocorticoid triamcinolone acetonide when administered on day 1 after smoking cessation. RESULTS: Exposure to CSS resulted in an increase in laryngeal mucus secretion that was further excacerbated following smoking cessation. This change coincided with an increase in the expression of mRNA for the inflammatory cytokines tumor necrosis factor and interleukin-6, as well as mRNA for MUC5AC, which is involved in mucin production. Triamcinolone suppressed CSS-induced laryngeal mucus hypersecretion and pro-inflammatory cytokine production. CONCLUSION: Cigarette smoke-associated inflammation may contribute to the exacerbated laryngeal mucus hypersecretion that occurs following smoking cessation. The inflammatory response represents a promising target for the treatment of cigarette smoke-associated mucus hypersecretion.

Role of lifestyle modifications for patients with laryngeal granuloma caused by gastro-esophageal reflux: comparison between conservative treatment and the surgical approach.

CONCLUSIONS: It is considered that a regimen combining pharmacologic management and lifestyle modifications is the most effective treatment for laryngeal granulomas caused by GER. OBJECTIVES: This study compared the results of the combination therapy and surgery to determine the best treatment of laryngeal granuloma caused by gastro-esophageal reflux in 51 patients. METHODS: Prospective study. RESULTS: In the conservative treatment group, the CR rate was 89.7% and recurrence rate was 2.6%, while the lesions remained in patients (7.7%). This study compared the CR and recurrence rates between conservative treatment and surgery for granuloma. The results showed that the laryngeal granuloma recurrence rate was significantly lower with the conservative treatment regimen compared with surgery (p = .0016).

Independent exercise for glottal incompetence to improve vocal problems and prevent aspiration pneumonia in the elderly: a randomized controlled trial.

OBJECTIVES: To evaluate the effect of a self-controlled vocal exercise in elderly people with glottal closure insufficiency. DESIGN: Parallel-arm, individual randomized controlled trial. METHODS: Patients who visited one of 10 medical centers under the National Hospital Organization group in Japan for the first time, aged 60 years or older, complaining of aspiration or hoarseness, and endoscopically confirmed to have glottal closure insufficiency owing to vocal cord atrophy, were enrolled in this study. They were randomly assigned to an intervention or a control group. The patients of the intervention group were given guidance and a DVD about a self-controlled vocal exercise. The maximum phonation time which is a measure of glottal closure was evaluated, and the number of patients who developed pneumonia during the six months was compared between the two groups. RESULTS: Of the 543 patients enrolled in this trial, 259 were allocated into the intervention group and 284 into the control; 60 of the intervention group and 75 of the control were not able to continue the trial. A total of 199 patients (age 73.9 ±7.25 years) in the intervention group and 209 (73.3 ±6.68 years) in the control completed the six-month trial. Intervention of the self-controlled vocal exercise extended the maximum phonation time significantly ( p < 0.001). There were two hospitalizations for pneumonia in the intervention group and 18 in the control group, representing a significant difference ( p < 0.001). CONCLUSION: The self-controlled vocal exercise allowed patients to achieve vocal cord adduction and improve glottal closure insufficiency, which reduced the rate of hospitalization for pneumonia significantly. CLINICAL TRIAL: gov Identifier-UMIN000015567.

Giant fibrovascular polyp in the hypopharynx: a case report and review of the literature.

INTRODUCTION: Fibrovascular polyps (FVPs) are benign tumors that commonly occur in the cervical esophagus. Few cases of FVPs of the hypopharynx have been reported, but there has been no English review concerning hypopharyngeal FVPs (hFVPs). Here, we report a case of a vast hFVP, and we also review 13 hFVP cases found in the English literature (PubMed search) including our case. CASE DESCRIPTION: A 41-year-old man with respiratory distress and regurgitation of a mass was referred to our hospital. Endoscopic and radiographic evaluations were required for diagnosis. The tumor originated from the hypopharynx and covered almost the entire larynx, which caused the airway to narrow. An emergency surgical removal was performed under general anesthesia with orotracheal intubation, and the tumor was completely removed transorally using a laryngeal endoscope. Pathological examination revealed that the mass was a FVP. DISCUSSION AND EVALUATION: We investigated patient characteristics, symptoms, polyp size, treatments, and recurrence of 13 hFVP cases. Regurgitation of a mass, dyspnea, and dysphagia were frequently reported symptoms at presentation. All patients were treated by surgical excision with no recurrence. Airway management is critical and tracheotomies were needed in some cases. CONCLUSIONS: FVPs are often asymptomatic, and they can suddenly cause respiratory distress from laryngeal blockage. Therefore, we emphasize that when such cases are encountered, airway management and surgical treatment should be considered as early as possible.

Visualization and Estimation of Vibratory Disturbance in Vocal Fold Scar Using High-Speed Digital Imaging.

OBJECTIVE: To explore the method to visualize and quantify the abnormality of vocal fold vibration in vocal fold scar (VFS) using high-speed digital imaging (HSDI). METHODS: HSDI was performed on 12 patients (2 men and 10 women) with VFS and 46 vocally healthy subjects (17 men and 29 women), and the obtained data were quantitatively evaluated by frame-by-frame analysis, laryngotopography (LTG), single-line and multiline kymography, and glottal area waveform. RESULTS: Visualization of a scarred area was feasible in 75% of VFS in the present study using LTG. Quantitative HSDI analysis revealed that VFS had poorer glottal closure (eg, larger open quotients, larger minimal glottal area), reduced vibration in a scarred area (eg, smaller mucosal wave magnitude, mucosal wave persistence, lateral peak index), and greater asymmetry (eg, amplitude difference, mucosal wave magnitude difference, lateral phase difference) than the control group. Correlation study revealed moderate correlations between HSDI-derived parameters and conventional acoustic or aerodynamic parameters (eg, period perturbation quotient). CONCLUSIONS: HSDI is considered to be useful in the diagnosis of VFS, visualization of a scarred area, and quantification of vibratory abnormality.

Quantitative Analysis of Vocal Fold Vibration in Vocal Fold Paralysis With the Use of High-speed Digital Imaging.

INTRODUCTION: The goal of this work was to objectively elucidate the vibratory characteristics of vocal fold paralysis (VFP) using high-speed digital imaging (HSDI). METHODS: HSDI was performed in 29 vocally healthy subjects (12 women and 17 men) and in 107 patients with VFP (40 women and 67 men). Then, the HSDI data were evaluated by visual-perceptual rating, single-line kymography, multiline kymography, laryngotopography, and glottal area waveform analysis. RESULTS: Patients with VFP compared with vocally healthy subjects revealed more frequent incomplete glottal closure, greater asymmetry in amplitude, mucosal wave, frequency, and phase, as well as larger open quotient, smaller speed index, larger maximal and minimal glottal area, and smaller glottal area difference. Paralyzed vocal folds in VFP revealed reduced mucosal wave than nonparalyzed vocal folds in VFP or in intact vocal folds in vocally healthy subjects. CONCLUSIONS: HSDI was effective in documenting the characteristics of vocal fold vibrations in patients with VFP and in exploring the vibratory disturbance for estimating the severity of dysphonia.