Longitudinal Analysis of Dysphagia and Factors Related to Postoperative Pneumonia in Patients Undergoing Esophagectomy for Esophageal Cancer.

Few studies have quantified longitudinal changes in swallowing in patients undergoing esophagectomy for esophageal cancer. This study longitudinally analyzed the changes in the Modified Barium Swallow Study Impairment Profile (MBSImP™) scores, swallowing kinematic measurements, and swallowing-related symptoms in patients undergoing esophagectomy. We also examined the association between identified swallowing impairment and aspiration pneumonia after surgery. We included consecutive patients who underwent esophagectomy and completed laryngoscopy and videofluoroscopy before, two weeks, and three months after surgery. We analyzed physiological impairments using the MBSImP. We also assessed the swallowing kinematics on a 5 mL thickened liquid bolus at three time points. Vocal fold mobility was assessed using a laryngoscope. Repeated measures were statistically examined for longitudinal changes in swallowing function. The association between the significant changes identified after esophagectomy and aspiration pneumonia was tested. Twenty-nine patients were included in this study. Preoperative swallowing function was intact in all participants. The timing of swallowing initiation and opening of the pharyngoesophageal segment remained unchanged after surgery. Tongue base retraction and pharyngeal constriction ratio worsened two weeks after surgery but returned to baseline levels three months after surgery. Three months after surgery, hyoid displacement and vocal fold immobility did not fully recover. Aspiration pneumonia occurred in nine patients after surgery and was associated with postoperative MBSImP pharyngeal residue scores. Decreased hyoid displacement and vocal fold immobility were observed postoperatively and persisted for a long time. The postoperative pharyngeal residue was associated with pneumonia and thus should be appropriately managed after surgery.

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.

Swallowing computed tomography and virtual reality as novel imaging modalities for the diagnosis of clicking larynx: Two case reports.

Globus sensation and pain causes are difficult to identify by conventional examination methods. With technology advances, new imaging methods including swallowing computed tomography (CT) and virtual reality (VR) have emerged and are contributing to definite diagnoses. We report two cases of cervical discomfort diagnosed as clicking larynx using swallowing CT/VR . Case 1 is a 55-year-old man. There were no findings on laryngoscopy or swallowing examinations, but swallowing CT/VR showed that the thyroid cartilage collided with the hyoid bone during swallowing, leading to the diagnosis of a clicking larynx. The patient was obese and is under observation hoping that weight loss will improve symptoms. Case 2 is a 32-year-old transgender man. He is receiving male hormones for gender identity disorder. He was diagnosed with a clicking larynx using swallowing CT/VR. Hormonal therapy may have increased the size of the thyroid cartilage, likely causing the symptoms. As they didn't choose surgical treatment, no symptomatic relief was achieved, but identifiying the cause contributed to improved patient satisfaction. Swallowing CT/VR is useful not only for evaluating the swallowing function, but also the underlying etiology of globus sensation and pain upon swallowing. Further clinical applications of this technique are expected for motion induced cervical symptoms.

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.

Sex and Age Stratified Voice Data in Japanese Vocally Healthy Individuals: Vocal Capacity.

OBJECTIVE: There is no normative voice dataset regarding the vocal capacity of Japanese speakers in the English literature. We collected age- and sex-stratified data on the vocal capacity of vocally healthy Japanese speakers. METHODS: In total, 111 vocally healthy Japanese speakers (42 men and 69 women) were divided into the young (13 men and 30 women), middle-aged (18 men and 27 women), and elderly (11 men and 12 women) groups. Participants underwent duration-, intensity-, and pitch-related vocal capacity tests using either a conventional method or an aerodynamic method or both. The data obtained were statistically analyzed in terms of age and sex. RESULTS: Overall, the duration- and pitch-related parameters measured by the conventional method were generally comparable to the previous results in the literature, while duration-, pitch-, and intensity-related parameters measured by the aerodynamic method differed significantly from them. Significant sex differences were noted in all parameters in the duration-, intensity-, and pitch-related vocal capacity tests. Furthermore, significant age-related changes were observed in all parameters, except for the mean flow rate and highest pitch measured by the aerodynamic method. CONCLUSION: This study is the first to provide a sex- and age-stratified database of the normative vocal capacity data of Japanese speakers. However, further improvements will be needed in the assessment protocols, conditions, or devices used for the duration-, intensity-, and pitch-related vocal capacity tests in the aerodynamic method.

Gender- and Age- Stratified Normative Voice Data in Japanese-Speaking Subjects: Analysis of Sustained Habitual Phonations.

INTRODUCTION: There is no normative voice dataset for Japanese speakers in the English literature. We constructed age- and gender-stratified normative voice data with the assistance of vocally healthy Japanese speakers. METHODS: A total of 111 vocally healthy Japanese speakers (42 men, 69 women) were divided into young (13 men, 30 women), middle-aged (18 men, 27 women), and elderly (11 men, 12 women) groups. Participants underwent aerodynamic, acoustic, and audio-perceptual studies of sustained habitual vowel phonations, and the obtained data were statistically analyzed in terms of age and gender. RESULTS: Both gender- and age-related differences were noted in fundamental frequencies, sound pressure level, shimmer, and amplitude perturbation quotient, while only gender-related differences were noted in mean flow rate and only age-related changes were observed in subglottal pressure; laryngeal resistance; and G, R, B, and S scores of the GRBAS scale. The gender- and age-related difference data were comparable with the reported data in other languages, ethnicities, or countries. CONCLUSIONS: The present study is the first to provide a database of normative voice data of Japanese speakers. The idiosyncrasy of Japanese is considered minor in sustained habitual vowel phonations.

Safety of surgical tracheostomy under continued antithrombotic therapy: A retrospective cohort study.

OBJECTIVE: Although various guidelines have been established for the management of antithrombotic therapy during surgical treatments, surgical tracheostomy (ST) under continued antithrombotic therapy (CAT) remains challenging. Here, we investigated the risk factors for complications after ST by focusing on the application of CAT during ST. DESIGN: A retrospective cohort study with medical records from 2009 to 2020. SETTING: A single-center study. PARTICIPANTS: This study included patients who had undergone ST at the Department of Otolaryngology of our hospital MAIN OUTCOME MEASURES: The primary outcomes were the incidence of complications and blood test results. Secondary outcomes were risk factors for postoperative complications. RESULTS: We identified 288 patients (median age: 64 years; 184 men [64%]), among whom 40 (median age: 67 years; 29 men [73%]) underwent CAT. Although the patients undergoing CAT had significantly longer activated partial thromboplastin time (p=0.002) and a higher prothrombin time-international normalized ratio (p=0.006) compared to antithrombotic naïve patients, no statistically significant intergroup differences were observed for the risk of bleeding, infection, or subcutaneous emphysema. Instead, ST under local anesthesia (p=0.01) and ST for airway emergency (p=0.02) significantly increased the risk of early postoperative complications. CONCLUSION: These results suggest that ST under CAT can be safely performed without any increased risk of postoperative complications. Nevertheless, surgeons should be extra cautious about early complications after ST under local anesthesia without intubation or ST for airway emergencies.

Risk Factors for Aspiration Pneumonia After Receiving Liquid-Thickening Recommendations.

OBJECTIVE: We examined the influence of liquid thickness levels on the frequency of liquid penetration-aspiration in patients with dysphagia and evaluated the clinical risk factors for penetration-aspiration and aspiration pneumonia development. STUDY DESIGN: A case series. SETTING: Single-institution academic center. METHODS: We reviewed medical charts from 2018 to 2019. First, we evaluated whether liquid thickness levels influence the frequency of liquid penetration-aspiration in patients with dysphagia. Penetration-aspiration occurrence in a videofluoroscopic swallowing study was defined as Penetration-Aspiration Scale (PAS) scores ≥3. Second, the association between liquid thickness level and penetration-aspiration was analyzed, and clinical risk factors were identified. Moreover, clinical risk factors for aspiration pneumonia development within 6 months were investigated. RESULTS: Of 483 patients, 159 showed penetration-aspiration. The thickening of liquids significantly decreased the incidence of penetration-aspiration (P < .001). Clinical risk factors for penetration-aspiration were vocal fold paralysis (odds ratio [OR], 1.99), impaired laryngeal sensation (OR, 5.01), and a history of pneumonia (OR, 2.90). Twenty-three patients developed aspiration pneumonia while undertaking advised dietary changes, including liquid thickening. Significant risk factors for aspiration pneumonia development were poor performance status (OR, 1.85), PAS score ≥3 (OR, 4.03), and a history of aspiration pneumonia (OR, 7.00). CONCLUSION: Thickening of liquids can reduce the incidence of penetration-aspiration. Vocal fold paralysis, impaired laryngeal sensation, and history of aspiration pneumonia are significant risk factors of penetration-aspiration. Poor performance status, PAS score ≥3, and history of aspiration pneumonia are significantly associated with aspiration pneumonia development following recommendations on thickening liquids. LEVEL OF EVIDENCE: 3.

Effects of Aspiration Prevention Surgery on the Dynamics of the Pharynx and Upper Esophageal Sphincter.

OBJECTIVE: Oral intake after aspiration prevention surgery (APS) is influenced by postoperative pharyngeal pressure and the dynamics of the upper esophageal sphincter (UES). We examined the effects of less invasive APS combined with UES relaxation techniques (laryngeal closure with cricopharyngeal myotomy [LC-CPM] and central-part laryngectomy [CPL]) on pharyngeal pressure and UES dynamics. STUDY DESIGN: Retrospective, observational study. SETTING: Single center. METHODS: We assessed the high-resolution pharyngeal manometric parameters of patients who underwent APS from 2018 to 2020. Then, we compared the effects of bilateral cricopharyngeal myotomy (combined with LC: LC-CPM group) and total cricoidectomy (CPL group) on both pharyngeal pressure and UES dynamics pre- and postoperatively. RESULTS: Eighteen patients (median age, 68 years; 17 men [94%]) were enrolled. Primary diseases associated with severe aspiration were neuromuscular disorders in 13, stroke in 3, and others in 2 patients. Pharyngeal swallowing pressure did not significantly change before and after APS. UES resting pressure and UES relaxation duration were significantly reduced (P < .001) and prolonged (P < .001), respectively, after APS. Only the CPL group (8 patients: median 62 years, all men) showed an increase in the velopharyngeal closure integral after APS (P < .05). More prolonged UES relaxation duration was recognized postoperatively in the CPL group (P < .01) than in the LC-CPM group. CONCLUSION: Less invasive APS minimally affects pharyngeal swallowing pressure, decreases UES resting pressure, and prolongs UES relaxation duration. CPL may be more effective for postoperative UES relaxation in patients with a short UES relaxation time.

Multivariate Analysis of Vocal Fold Vibrations in Normal Speakers Using High-Speed Digital Imaging.

INTRODUCTION: Little is known about the normal variations in vocal fold vibrations. We conducted a prospective study on normal subjects using high-speed digital imaging (HSDI) to elucidate key parameters regarding age/gender-related normal variations. METHODS: Forty-six healthy adult volunteers were divided into young (aged ≤35 years) male, young female, elderly (aged ≥65 years) male, and elderly female subgroups. HSDI data of sustained phonation of /i/ at a comfortable pitch and loudness were obtained, and vibratory parameters were calculated using the visual-perceptual rating, laryngotopography, digital kymography, and glottal area waveform. Multivariate analysis was then performed on these parameters to clarify the subgroup-specific key parameters. RESULTS: Four key parameters were identified from a total of 83: one from visual perceptual rating and three from laryngotopography. Subgroup analyses showed that posterior-to-anterior longitudinal phase difference (PD) and high fundamental frequency (F0) were specific to young female participants. A low F0 was specific to young male participants. Large anterior-to-posterior longitudinal PD and its left-right difference were specific to elderly male participants. There were no key parameters for elderly female participants. CONCLUSIONS: Methods that can assess F0 and longitudinal PD, such as visual-perceptual rating and laryngotopography, were effective in the evaluation of normal vocal fold vibrations and their variations.

Expression of ACE2 and TMPRSS2 Proteins in the Upper and Lower Aerodigestive Tracts of Rats: Implications on COVID 19 Infections.

OBJECTIVE: Patients with coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), exhibit not only respiratory symptoms but also symptoms of chemo-sensitive disorders. Cellular entry of SARS-CoV-2 depends on the binding of its spike protein to a cellular receptor named angiotensin-converting enzyme 2 (ACE2), and the subsequent spike protein-priming by host cell proteases, including transmembrane protease serine 2 (TMPRSS2). Thus, high expression of ACE2 and TMPRSS2 is considered to enhance the invading capacity of SARS-CoV-2. METHODS: To elucidate the underlying histological mechanisms of the aerodigestive disorders caused by SARS-CoV-2, we investigated the expression of ACE2 and TMPRSS2 proteins using immunohistochemistry, in the aerodigestive tracts of the tongue, hard palate with partial nasal tissue, larynx with hypopharynx, trachea, esophagus, and lung of rats. RESULTS: Co-expression of ACE2 and TMPRSS2 proteins was observed in the taste buds of the tongue, nasal epithelium, trachea, bronchioles, and alveoli with varying degrees of expression. Remarkably, TMPRSS2 expression was more distinct in the peripheral alveoli than in the central alveoli. These results coincide with the reported clinical symptoms of COVID-19, such as the loss of taste, loss of olfaction, and respiratory dysfunction. CONCLUSIONS: A wide range of organs have been speculated to be affected by SARS-CoV-2 depending on the expression levels of ACE2 and TMPRSS2. Differential distribution of TMPRSS2 in the lung indicated the COVID-19 symptoms to possibly be exacerbated by TMPRSS2 expression. This study might provide potential clues for further investigation of the pathogenesis of COVID-19. LEVEL OF EVIDENCE: NA Laryngoscope, 131:E932-E939, 2021.

Esophageal Dysmotility is Common in Patients With Multiple System Atrophy.

OBJECTIVES: Esophageal dysmotility (ED) in patients with multiple system atrophy (MSA) are poorly understood. This study aimed to investigate the prevalence of ED in patients with MSA and to assess the relationship of esophageal abnormalities with other clinical findings and characteristics in these patients. METHODS: A retrospective chart review was conducted to identify patients with MSA and to compare them to the elderly controls without MSA (65+ years) who underwent a videofluorographic esophagram from 2014 to 2019. Disease type, disease severity, vocal fold mobility impairment, abnormal deglutitive proximal esophageal contraction (ADPEC), and intra-esophageal stasis (IES) were reviewed and compared between groups. RESULTS: Thirty-seven patients with MSA were identified. The median age was 63 and 26 (70%) were male. These patients were matched to 22 elderly adults with presbylarynx but not MSA (median age 77, 68% male). In MSA patients, cerebellar variant type was predominant (59%), and ADPEC was recognized in 18 patients (49%). Disease severity level (P = 0.028) and existence of IES (P = 0.046) were associated with higher risks of developing ADPEC. The prevalence of IES was significantly higher in patients with MSA (95%) compared to controls without MSA (46%) (P < 0.001). Disease severity level and the existence of IES were significantly associated with the presence of ADPEC (p < 0.05). CONCLUSION: ADPEC and IES were significantly more common in MSA than in elderly subjects without MSA. MSA severity is associated with the development of ADPEC. The data suggest that esophageal motility is predominantly affected in MSA. LEVEL OF EVIDENCE: 3 Laryngoscope, 131:832-838, 2021.

The effects of barium concentration levels on the pulmonary inflammatory response in a rat model of aspiration.

PURPOSE: Barium sulfate (Ba) suspension is the most widely used contrast agent for upper gastrointestinal and videofluoroscopic swallow studies (VFSS). The effect of Ba concentration on lung injury is uncertain. The aims of this study were to explore the effects of different barium concentrations on the respiratory organs and elucidate the underlying mechanisms of these effects in an established animal model of aspiration. METHODS: Animal model study. Eight-week-old male Sprague-Dawley rats were allocated into three groups (n = 12, each group). Two groups underwent tracheal instillation of low (30% w/v) and high (60% w/v) concentration Ba (low-Ba, high-Ba). A control group was instilled with saline. Half of the animals were euthanized on day 2 and the remaining half were euthanized on day 30. Histological and gene analyses were performed. RESULTS: Both low-Ba and high-Ba aspiration caused inflammatory cell infiltration in the lung at 2 days post aspiration with an increase in the expression of inflammatory cytokines. At 30 days post aspiration, small quantities of barium particles remained in the lung of the low-Ba group without any inflammatory reaction. Chronic inflammation was recognized in the high-Ba group up to 30 days post aspiration. CONCLUSION: A small amount of high concentration Ba (60% w/v) caused sustained inflammation in the rat lung at least 30 days after aspiration. Even with a small amount of low concentration Ba aspiration (30% w/v), Ba particles can remain in the lung over a month, causing sustained late effects.

Choice of Aspiration Prevention Surgery for Patients With Neuromuscular Disorders: Report of Three Cases.

Dysphagia, one of the major complications of neuromuscular diseases such as Parkinson's disease and amyotrophic lateral sclerosis (ALS), decreases quality of life and may lead to malnutrition or aspiration pneumonia. Although recent reports have suggested that surgical aspiration prevention improves quality of life and enables oral intake, the selection of appropriate aspiration prevention techniques has rarely been discussed. In this report, we present the cases of three patients with neuromuscular diseases who underwent surgical aspiration prevention; we selected the surgical techniques based on analysis of the dysphagia mechanisms, disease progression, and general condition in each case. Case 1 was a 55-year-old man with multiple system atrophy (MSA) and presented with dysphagia associated with insufficient upper esophageal sphincter (UES) relaxation. We performed central-part laryngectomy, which was able to improve UES relaxation. Case 2 was a 79-year-old man with progressive supranuclear palsy who presented with respiratory disorder and dysphagia. Glottic closure under local anesthesia was selected because he also had acute hepatobiliary dysfunction and methicillin-resistant Staphylococcus aureus pneumonia with pleural effusion. Case 3 was a 75-year-old man with ALS and presented with respiratory disorder and mild dysphagia. Subglottic closure with total cricoidectomy was selected because his dysphagia was expected to worsen due to tracheostomy and disease progression. We also summarize the characteristics of the aspiration prevention surgical techniques based on our cases and on literature review. The causes of dysphagia, including insufficient UES opening during swallowing, weak pharyngeal constriction, velopharyngeal insufficiency, and inadequate laryngeal elevation, should be assessed by detailed examination before surgery, and the type of aspiration prevention surgery should be selected based on patient swallowing function and general condition.

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.

Characterization of Vocal Fold Vibration in Sulcus Vocalis Using High-Speed Digital Imaging.

Purpose: The aim of the present study was to qualitatively and quantitatively characterize vocal fold vibrations in sulcus vocalis by high-speed digital imaging (HSDI) and to clarify the correlations between HSDI-derived parameters and traditional vocal parameters. Method: HSDI was performed in 20 vocally healthy subjects (8 men and 12 women) and 41 patients with sulcus vocalis (33 men and 8 women). Then HSDI data were evaluated by assessing the visual-perceptual rating, digital kymography, and glottal area waveform. Results: Patients with sulcus vocalis frequently had spindle-shaped glottal gaps and a decreased mucosal wave. Compared with the control group, the sulcus vocalis group showed higher open quotient as well as a shorter duration of the visible mucosal wave, a smaller speed index, and a smaller glottal area difference index ([maximal glottal area - minimal glottal area]/maximal glottal area). These parameters deteriorated in order of the control group and Type I, II, and III sulcus vocalis. There were no gender-related differences. Strong correlations were noted between the open quotient and the type of sulcus vocalis. Conclusions: HSDI was an effective method for documenting the characteristics of vocal fold vibrations in patients with sulcus vocalis and estimating the severity of dysphonia.

High-speed Videolaryngoscopy: Quantitative Parameters of Glottal Area Waveforms and High-speed Kymography in Healthy Individuals.

OBJECTIVES: We conducted a study to obtain quantitative parameters of the vocal dynamic using high-speed videolaryngoscopy and to characterize the vocal fold vibration pattern of healthy individuals by analyzing glottal area waveforms and high-speed kymography. METHODS: Laryngeal images of 45 healthy individuals were captured using high-speed videolaryngoscopy. The open and speed quotients of the glottal area waveforms and high-speed kymography were obtained and statistically analyzed according to the gender of each individual. RESULTS: Glottal area waveforms revealed average values of 0.85 and 1.16 for open and speed quotients, respectively, for women, and 0.70 and 1.19 for men. Using high-speed kymography, quantitative parameters of open and speed quotients for women were 0.62 and 1.02, respectively, and for men were 0.57 and 1.12. By gender, a significant statistical difference emerged for open quotients obtained from both glottal area waveforms (P = 0.004) and high-speed kymography (P = 0.013). CONCLUSION: Obtained by using computational tools specifically for analyzing laryngeal images from high-speed videolaryngoscopy, quantitative parameters of glottal area waveforms and high-speed kymography in healthy individuals provide reference data and normality for future studies.

Quantification of Vocal Fold Vibration in Various Laryngeal Disorders Using High-Speed Digital Imaging.

OBJECTIVE: To quantify vibratory characteristics of various laryngeal disorders seen by high-speed digital imaging (HSDI). METHODS: HSDI was performed on 78 patients with various laryngeal disorders (20 with polyp, 16 with carcinoma, 13 with leukoplakia, 6 with vocal fold nodule, and 33 with others) and 29 vocally healthy subjects. Obtained data were quantitatively evaluated by frame-by-frame analysis, laryngotopography, digital kymography, and glottal area waveform. RESULTS: Overall, patients with laryngeal pathologies showed greater asymmetry in amplitude, mucosal wave and phase, smaller mucosal wave, and poorer glottal closure than vocally healthy subjects. Furthermore, disease-specific vibratory disturbances that generally agreed with the findings in the literature were quantified: comparing polyp with nodule, differences were noted in longitudinal phase difference, amplitude, and mucosal wave. In comparison with leukoplakia and cancer, nonvibrating area was more frequently noted in cancer. CONCLUSIONS: The HSDI analysis of various voice disorders using multiple methods can help phonosurgeons to properly diagnose various laryngeal pathologies and to estimate the degree of their vocal disturbances.

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.

Relationship of Various Open Quotients With Acoustic Property, Phonation Types, Fundamental Frequency, and Intensity.

INTRODUCTION: In the present study, we examined the relationship between various open quotients (Oqs) and phonation types, fundamental frequency (F0), and intensity by multivariate linear regression analysis (MVA) to determine which Oq best reflects vocal fold vibratory characteristics. METHODS: Using high-speed digital imaging (HSDI), a sustained vowel /e/ at different phonation types, F0s, and intensities was recorded from six vocally healthy male volunteers: the types of phonation included modal, falsetto, modal breathy, and modal pressed phonations; and each phonation was performed at different F0s and intensities. Electroglottography (EGG) and sound signals were simultaneously recorded with HSDI. From the obtained data, 10 conventional Oqs (four Oqs from the glottal area function, four kymographic Oqs, and two EGG-derived Oqs) and two newly introduced Oqs (Oq(edge)+ and Oq(edge)) were evaluated. And, relationships between various Oqs and phonation types, F0, and intensity were evaluated by MVA. RESULTS: Among the various Oqs, Oq(edge)+ and Oq(edge) revealed the strongest correlations with an acoustic property and could best describe changes in phonation types: Oq(edge) was found to be better than Oq(edge)¯. Oq(MLK), the average of five Oqs from five-line multiline kymography was a very good alternative to Oq(edge)¯. EGG-derived Oqs were able to differentiate between modal phonation and falsetto phonation, but it was necessary to consider the change of F0 simultaneously. MVA showed the changes in Oq values between modal and other phonation types, the degree of involvement of intensity, and no relationship between F0 and Oqs. CONCLUSIONS: Among Oqs evaluated in this study, Oq(edge)+ and Oq(edge) were considered to best reflect the vocal fold vibratory characteristics.