Effectiveness of FEES with artificial intelligence-assisted computer-aided diagnosis.

OBJECTIVES: FEES is a standard procedure for diagnosing dysphagia. However, appropriate evaluation of FEES findings is difficult for inexperienced evaluators. Recent progress in deep learning has highlighted the use of artificial intelligence-assisted computer-aided diagnosis (AI-assisted CAD) in medical applications. We investigated the detection accuracy of FEES findings evaluated by inexperienced evaluators with and without the use of CAD. METHODS: The algorithm for FEES-CAD was developed using 25,630 expert-annotated images. A total of 45 inexperienced evaluators from three groups of people (resident doctors, nurses, and medical students), evaluated 32 FEES videos from 32 patients. To confirm the effectiveness of FEES-CAD, first, 32 FEES videos were evaluated without the use of CAD. Second, one half was evaluated with, and one half without, the use of CAD. The detection accuracy of the FEES findings was investigated, and the evaluation results obtained with CAD were statistically compared with those obtained without CAD. RESULTS: In the first FEES evaluation, the total detection accuracy was 82.2 %. In the second evaluation, the total detection accuracy with CAD was 84.3 %, and that without CAD was 81.7 %. The detection accuracies by the resident doctors, nurses, and medical students with CAD were 90.1 %, 82.6 %, and 79.4 %, respectively, and those without CAD were 83.7 %, 80.9 % and 80.1 %, respectively. In the resident doctors, the detection accuracy was significantly better when CAD was used for evaluation, compared with the non-CAD evaluations. CONCLUSION: The present study demonstrated the effectiveness of FEES-CAD in improving the detection accuracy of resident doctors, however, the differences were small.

Flowchart for selecting an appropriate surgical airway in neurologically impaired pediatric intubated patients: a case series

Abstract Objective: Medical advances have resulted in increased survival rates of neurologically impaired children who may require mechanical ventilation and subsequent tracheostomy as a surgical airway. However, at present, there is no definite consensus regarding the timing and methods for placement of a surgical airway in a neurologically impaired intubated child who needs to be cared for over a long-term period. We therefore created a flowchart for the selection of a surgical airway for Neurologically Impaired Pediatric Patients (NIPPs). Methods: The flowchart includes information on the patients' backgrounds, such as intubation period, prognosis related to reversibility, and history of aspiration pneumonia. To evaluate the importance of the flowchart, first we conducted a survey of pediatricians regarding selection of a surgical airway, and we also evaluated the appropriateness of the flowchart among pediatricians and caregivers through questionnaire surveys which include satisfaction with the decision-making process, and postoperative course after discharge. Results: A total of 21 NIPPs with intubation underwent surgery and a total of 24 participants (14 pediatricians and 10 caregivers) completed the survey. The answers regarding the importance of the flowchart showed that eleven pediatricians had experience selecting of surgical airways, nine of whom had had experiences in which they had to make a difficult decision. The answers regarding the appropriateness of the flowchart revealed that all pediatricians and caregivers were satisfied with the decision-making process and postoperative course after discharge using the flowchart. Conclusions: The present study demonstrated the effectiveness of our flowchart for selecting an appropriate surgical airway in NIPP. By referring to our flowchart, pediatricians and caregivers are likely to be able to select an appropriate surgical airway, leading to increased satisfaction with the decision-making process and postoperative course. Level of Evidence: 4.

Flowchart for selecting an appropriate surgical airway in neurologically impaired pediatric intubated patients: a case series.

OBJECTIVE: Medical advances have resulted in increased survival rates of neurologically impaired children who may require mechanical ventilation and subsequent tracheostomy as a surgical airway. However, at present, there is no definite consensus regarding the timing and methods for placement of a surgical airway in a neurologically impaired intubated child who needs to be cared for over a long-term period. We therefore created a flowchart for the selection of a surgical airway for Neurologically Impaired Pediatric Patients (NIPPs). METHODS: The flowchart includes information on the patients' backgrounds, such as intubation period, prognosis related to reversibility, and history of aspiration pneumonia. To evaluate the importance of the flowchart, first we conducted a survey of pediatricians regarding selection of a surgical airway, and we also evaluated the appropriateness of the flowchart among pediatricians and caregivers through questionnaire surveys which include satisfaction with the decision-making process, and postoperative course after discharge. RESULTS: A total of 21 NIPPs with intubation underwent surgery and a total of 24 participants (14 pediatricians and 10 caregivers) completed the survey. The answers regarding the importance of the flowchart showed that eleven pediatricians had experience selecting of surgical airways, nine of whom had had experiences in which they had to make a difficult decision. The answers regarding the appropriateness of the flowchart revealed that all pediatricians and caregivers were satisfied with the decision-making process and postoperative course after discharge using the flowchart. CONCLUSIONS: The present study demonstrated the effectiveness of our flowchart for selecting an appropriate surgical airway in NIPP. By referring to our flowchart, pediatricians and caregivers are likely to be able to select an appropriate surgical airway, leading to increased satisfaction with the decision-making process and postoperative course.

Will levels of experience of examiners affect the diet provided for patients with swallowing impairment?

OBJECTIVE: Flexible endoscopic evaluation of swallowing (FEES) is widely performed to determine the safety of oral intake. However, evaluation results can vary among examiners depending on their experience. To analyze the impact of such differences, we investigated the diet provided for patients with swallowing impairment evaluated by experienced and inexperienced examiners. METHODS: We included 20 subjects with swallowing impairment. They underwent FEES twice, once by an experienced examiner (EE) and once by an inexperienced examiner (IE), in random order. The second FEES was generally performed within one month of the first FEES. The diet provided by the EE (EE results) and by the IE (IE results) during and after FEES was investigated and statistically compared. Respiratory and oral intake conditions at each time of FEES were also investigated and the results were included in the corresponding EE or IE results. RESULTS: The median interval between FEES was 13.5 days. There was no significant difference between the EE and IE results regarding swallowing impairment-related conditions, such as amount of sputum suctioned, oral intake status, or prevalence of fever after FEES. However, there was a significant difference in the texture-modified diet provided after FEES: A close-to-normal diet was provided by the EE compared to the diet provided by the IE. CONCLUSION: This study demonstrated a difference in the provided diet for patients with swallowing impairment between the examiners with different levels of experience. Our results suggest that EEs may be able to safely recommend patients with swallowing impairment have a close-to-normal diet.

Expert-level aspiration and penetration detection during flexible endoscopic evaluation of swallowing with artificial intelligence-assisted diagnosis.

Flexible endoscopic evaluation of swallowing (FEES) is considered the gold standard in diagnosing oropharyngeal dysphagia. Recent advances in deep learning have led to a resurgence of artificial intelligence-assisted computer-aided diagnosis (AI-assisted CAD) for a variety of applications. AI-assisted CAD would be a remarkable benefit in providing medical services to populations with inadequate access to dysphagia experts, especially in aging societies. This paper presents an AI-assisted CAD named FEES-CAD for aspiration and penetration detection on video recording during FEES. FEES-CAD segments the input FEES video and classifies penetration, aspiration, residue in the vallecula, and residue in the hypopharynx based on the segmented FEES video. We collected and annotated FEES videos from 199 patients to train the network and tested the performance of FEES-CAD using FEES videos from other 40 patients. These patients consecutively underwent FEES between December 2016 and August 2019 at Fukushima Medical University Hospital. FEES videos were deidentified, randomized, and rated by FEES-CAD and laryngologists with over 15 years of experience in performing FEES. FEES-CAD achieved an average Dice similarity coefficient of 98.6[Formula: see text]. FEES-CAD achieved expert-level accuracy performance on penetration (92.5[Formula: see text]), aspiration (92.5[Formula: see text]), residue in the vallecula (100[Formula: see text]), and residue in the hypopharynx (87.5[Formula: see text]) classification tasks. To the best of our knowledge, FEES-CAD is the first CNN-based system that achieves expert-level performance in detecting aspiration and penetration.

Cone beam computed tomography with oral contrast for accurate diagnosis and surgical planning of pharyngeal leakage and fistula: a case series

Abstract Objective: Pharyngocutaneous fistula is one of the severe complications related to head and neck surgeries. Detecting the accurate three-dimensional location of both the fistula and leakage is essential for surgical treatment. Videofluoroscopy is usually used for locating these; however, its imaging is two-dimensional. We evaluated pharyngeal leakage and fistulae using Cone Beam Computed Tomography (CBCT), known for its three-dimensional high spatial resolution imaging, taken in a sitting position, with oral contrast (contrast CBCT). Methods: Pharyngeal leakage and fistulae were evaluated in a total of 31 subjects by sequentially performing videofluoroscopy and contrast CBCT. The detection accuracy of videofluoroscopy and contrast CBCT for leakage and fistula, as well as the ability to determine the extent and depth for surgical planning, were investigated and compared. Results: Videofluoroscopy and contrast CBCT showed suspicious leakage and/or fistula in six and three of the 31 subjects, respectively. Surgical findings revealed the presence of leakage and/or fistula in three of the 31 subjects. The positive predictive values of videofluoroscopy and contrast CBCT were 50% (3/6) and 100% (3/3), respectively. Contrast CBCT provided more precise images, showing the extent and depth of leakage and fistula in three-dimensions. Conclusion: The present study's results indicate the usefulness of contrast CBCT in terms of accurate diagnosis of leakage and fistula, due to its three-dimensional imaging being performed with the patient in a sitting position. Level of evidence: 4.

Using the larynx as a last resort for oral intake in a hypopharyngeal cancer patient.

We present a new oral intake route in a hypopharyngeal cancer patient with severe complications. A 64-year-old man was diagnosed as having T2N0M0 squamous cell carcinoma of the posterior wall of the hypopharynx. He had previously undergone radiotherapy for laryngeal cancer and tricuspid valve replacement surgery, and also had atrial flutter and renal dysfunction. We performed surgery with curative intent. The hypopharynx was primarily closed after tumor resection. Laryngotracheal separation and tracheoesophageal diversion with end-to-end anastomosis of the trachea to the esophagus was performed. After surgery, complete oral feeding was achieved using the new pathway created. The larynx, contradictory to its typical role, can be used as a pathway to the esophagus using our revolutionary technique.

Cone beam computed tomography with oral contrast for accurate diagnosis and surgical planning of pharyngeal leakage and fistula: a case series.

OBJECTIVE: Pharyngocutaneous fistula is one of the severe complications related to head and neck surgeries. Detecting the accurate three-dimensional location of both the fistula and leakage is essential for surgical treatment. Videofluoroscopy is usually used for locating these; however, its imaging is two-dimensional. We evaluated pharyngeal leakage and fistulae using Cone Beam Computed Tomography (CBCT), known for its three-dimensional high spatial resolution imaging, taken in a sitting position, with oral contrast (contrast CBCT). METHODS: Pharyngeal leakage and fistulae were evaluated in a total of 31 subjects by sequentially performing videofluoroscopy and contrast CBCT. The detection accuracy of videofluoroscopy and contrast CBCT for leakage and fistula, as well as the ability to determine the extent and depth for surgical planning, were investigated and compared. RESULTS: Videofluoroscopy and contrast CBCT showed suspicious leakage and/or fistula in six and three of the 31 subjects, respectively. Surgical findings revealed the presence of leakage and/or fistula in three of the 31 subjects. The positive predictive values of videofluoroscopy and contrast CBCT were 50% (3/6) and 100% (3/3), respectively. Contrast CBCT provided more precise images, showing the extent and depth of leakage and fistula in three-dimensions. CONCLUSION: The present study's results indicate the usefulness of contrast CBCT in terms of accurate diagnosis of leakage and fistula, due to its three-dimensional imaging being performed with the patient in a sitting position.

Regenerative potential of basic fibroblast growth factor contained in biodegradable gelatin hydrogel microspheres applied following vocal fold injury: Early effect on tissue repair in a rabbit model / Potencial regenerativo do fator básico de crescimento de fibroblastos contido em microesferas biodegradáveis de hidrogel de gelatina aplicadas após lesão de prega vocal: efeito inicial no reparo tecidual em modelo de coelho

Abstract Introduction Postoperative dysphonia is mostly caused by vocal fold scarring, and careful management of vocal fold surgery has been reported to reduce the risk of scar formation. However, depending on the vocal fold injury, treatment of postoperative dysphonia can be challenging. Objective The goal of the current study was to develop a novel prophylactic regenerative approach for the treatment of injured vocal folds after surgery, using biodegradable gelatin hydrogel microspheres as a drug delivery system for basic fibroblast growth factor. Methods Videoendoscopic laryngeal surgery was performed to create vocal fold injury in 14 rabbits. Immediately following this procedure, biodegradable gelatin hydrogel microspheres with basic fibroblast growth factor were injected in the vocal fold. Two weeks after injection, larynges were excised for evaluation of vocal fold histology and mucosal movement. Results The presence of poor vibratory function was confirmed in the injured vocal folds. Histology and digital image analysis demonstrated that the injured vocal folds injected with gelatin hydrogel microspheres with basic fibroblast growth factor showed less scar formation, compared to the injured vocal folds injected with gelatin hydrogel microspheres only, or those without any injection. Conclusion A prophylactic injection of basic fibroblast growth factor -containing biodegradable gelatin hydrogel microspheres demonstrates a regenerative potential for injured vocal folds in a rabbit model.

Resumo Introdução A disfonia pós-operatória é causada principalmente por cicatrizes nas pregas vocais. Tem sido relatado que o manejo cuidadoso da cirurgia das pregas vocais reduz o risco de formação de cicatriz. No entanto, a depender da lesão da prega vocal, o tratamento da disfonia pós-operatória pode ser desafiador. Objetivo Desenvolver uma nova abordagem regenerativa profilática para o tratamento de pregas vocais lesionadas após a cirurgia, com microesferas biodegradáveis de hidrogel de gelatina como sistema de administração de medicamentos para o Fator Básico de Crescimento de Fibroblastos (bFGF). Método A cirurgia laríngea videoendoscópica foi feita para criar lesão nas pregas vocais em 14 coelhos. Imediatamente após esse procedimento, microesferas biodegradáveis de hidrogel de gelatina com bFGF foram injetadas na prega vocal. Duas semanas após a injeção, as laringes foram excisadas para avaliação da histologia das pregas vocais e do movimento da mucosa. Resultados A presença de função vibratória deficiente foi confirmada nas pregas vocais lesionadas. A histologia e a análise de imagem digital demonstraram que as pregas vocais lesionadas injetadas com microesferas de hidrogel de gelatina com bFGF apresentaram menor formação de cicatriz, em comparação com as pregas vocais lesionadas injetadas apenas com microesferas de hidrogel de gelatina ou aquelas sem injeção. Conclusão Uma injeção profilática de microesferas biodegradáveis de hidrogel de gelatina com bFGF demonstra um potencial regenerativo para pregas vocais lesionadas em um modelo de coelho.

Multicenter Study of Congenital Middle Ear Anomalies. Report on 246 Ears.

OBJECTIVES/HYPOTHESIS: Congenital middle ear anomalies represent a relatively rare condition. This study aimed to describe the characteristics and the surgical outcomes for patients with middle ear anomalies. METHODS: A multicenter study was conducted of consecutive patients with congenital middle ear anomalies who underwent primary surgical treatment between January 2008 and December 2017. Demographics, surgical procedures, and audiometric data were registered into the institutional database. Hearing changes and postoperative air-bone gap (ABG) were evaluated 1 year after surgery. RESULTS: A total of 246 patients (246 ears) (median age: 14 years, range: 4-75 years old) were included in this study. Anomalies were subdivided using the Teunissen and Cremers classification: 53 ears (22%) were categorized as class I, comprising only stapes ankylosis; 35 ears (14%) as class II, having ossicular chain anomalies with stapes ankylosis; 139 ears (57%) as class III, having ossicular chain anomalies with a mobile stapes-footplate; and 19 ears (8%) as class IV, with aplasia of the oval window. Evaluation of hearing outcomes for 198 ears with more than 1 year of follow-up revealed that good postoperative ABG (≤20 dB) was achieved in 82% of class I, 68% of class II, 74% of class III, and 23% of class IV anomalies. The postoperative ABG in class IV was significantly worse than in class I (P < .001) or class III (P < .01). CONCLUSIONS: This study demonstrated that class III anomalies comprised the majority of middle ear anomalies and surgical outcomes for class IV anomalies are unfavorable. LEVEL OF EVIDENCE: 4 Laryngoscope, 131:E2323-E2328, 2021.

Decannulation after cricotracheostomy: a comparison of partial cricoid cartilage resection with conventional tracheostomy.

BACKGROUND: Cricotracheostomy, a modified procedure to open the airway with partial cricoid cartilage resection, was recently reported to be useful in selected cases. AIMS/OBJECTIVES: To examine decannulation outcomes in patients who underwent cricotracheostomy by comparing it with a conventional tracheostomy. MATERIALS AND METHODS: Data from 127 consecutive adult patients, who underwent either conventional tracheostomy or cricotracheostomy between 2016 and 2019, were collected and analyzed with respect to subsequent decannulation with stoma closure. RESULTS: Conventional tracheostomy and cricotracheostomy were performed in 94 and 33 patients, respectively. The most frequent reason for choosing cricotracheostomy was a physiological low-lying larynx (n = 12). After excluding 30 patients who were considered ineligible due to their primary disease, subsequent decannulation with stoma closure was achieved in 35 (46%) of 76 cases with conventional tracheostomy and seven (33%) of 21 cases with cricotracheostomy, showing no significant difference (p = .33). CONCLUSIONS/SIGNIFICANCE: Compared with a conventional tracheostomy, cricotracheostomy had an acceptable decannulation outcome. However, it should be emphasized that an appropriate selection of patients is required on considering the advantages of cricotracheostomy.

Regenerative potential of basic fibroblast growth factor contained in biodegradable gelatin hydrogel microspheres applied following vocal fold injury: Early effect on tissue repair in a rabbit model.

INTRODUCTION: Postoperative dysphonia is mostly caused by vocal fold scarring, and careful management of vocal fold surgery has been reported to reduce the risk of scar formation. However, depending on the vocal fold injury, treatment of postoperative dysphonia can be challenging. OBJECTIVE: The goal of the current study was to develop a novel prophylactic regenerative approach for the treatment of injured vocal folds after surgery, using biodegradable gelatin hydrogel microspheres as a drug delivery system for basic fibroblast growth factor. METHODS: Videoendoscopic laryngeal surgery was performed to create vocal fold injury in 14 rabbits. Immediately following this procedure, biodegradable gelatin hydrogel microspheres with basic fibroblast growth factor were injected in the vocal fold. Two weeks after injection, larynges were excised for evaluation of vocal fold histology and mucosal movement. RESULTS: The presence of poor vibratory function was confirmed in the injured vocal folds. Histology and digital image analysis demonstrated that the injured vocal folds injected with gelatin hydrogel microspheres with basic fibroblast growth factor showed less scar formation, compared to the injured vocal folds injected with gelatin hydrogel microspheres only, or those without any injection. CONCLUSION: A prophylactic injection of basic fibroblast growth factor -containing biodegradable gelatin hydrogel microspheres demonstrates a regenerative potential for injured vocal folds in a rabbit model.

Clinical characteristics, the diagnostic criteria and management recommendation of otitis media with antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (OMAAV) proposed by Japan Otological Society.

Anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) is a form of necrotizing vasculitis with few or no immune deposits. It primarily affects small and medium blood vessels. AAV is classified into three categories, granulomatosis with polyangiitis (GPA), microscopic polyangiitis (MPA) and eosinophilic granulomatosis with polyangitis (EGPA), and two major ANCAs, proteinase 3 (PR3)-ANCA or myeloperoxidase (MPO)-ANCA are involved in their pathogenesis. Intractable otitis media frequently occurs in patients with GPA, MPA or EGPA, although all patients show similar clinical features, regardless of the type of AAV. Furthermore, approximately 15% patients with otitis media caused by AAV do not show ANCA positivity, histopathological evidence, or any other AAV-related lesions at the initial visit; therefore, these patients do not fulfill the ordinary diagnostic criteria for systemic AAV. Thus, we first proposed that this condition could be categorized as "otitis media with AAV (OMAAV)". Subsequently, the Japanese Otological Society (JOS) conducted a nationwide survey between December 2013 and February 2014 and identified 297 patients with OMAAV. The survey revealed that OMAAV is a disease that initially occurs in the middle ear and subsequently spreads to other organs such as the lungs and kidneys, with eventual involvement of all body organs. Severe sequelae such as facial palsy, hypertrophic pachymeningitis, complete deafness, and subarachnoid hemorrhage resulting in death can also occur. In this review, we introduce the clinical features, diagnostic criteria, and treatment strategies recommended by JOS for early diagnosis and treatment of OMAAV.

Implementing a flexible endoscopic evaluation of swallowing at elderly care facilities to reveal characteristics of elderly subjects who screened positive for a swallowing disorder.

OBJECTIVES: The risk of aspiration pneumonia has been reported to increase with age, especially in elderly residents of nursing homes. However, the characteristics of those with swallowing impairments at elderly care facilities have not yet been evaluated using reliable instrumental examinations. The aims of the current study were to investigate the frequency of swallowing impairment and determine the characteristics of the elderly with swallowing disorders residing at care facilities. METHODS: To reveal the characteristics of the elderly with swallowing disorders, questionnaires for dysphagia screening and flexible endoscopic evaluation of swallowing (FEES) were used. Regarding the dysphagia screening, two types of questionnaires were sent to 451 elderly persons aged 65 years and older who were living in facilities for the elderly in Japan. FEES was performed to assess swallowing impairment at each facility for those who were found to be positive for dysphagia by the questionnaires. The frequency of swallowing impairment and the characteristics of elderly subjects with swallowing disorders were investigated. RESULTS: Among 413 subjects who completed both questionnaires, 229 were screened positive for dysphagia, 160 of whom underwent FEES. Swallowing impairment was observed in 93 subjects. The subjects with swallowing impairment had a significantly high prevalence of fever, sputum, and/or history of aspiration pneumonia. Their oral intake ability and activities of daily living were significantly low. CONCLUSION: We demonstrated the frequency of swallowing disorders and the characteristics of elderly subjects with swallowing disorders living in care facilities using FEES. Our results suggest the importance of screening all elderly care facility residents for dysphagia.

A summary of the Clinical Practice Guideline for the Diagnosis and Management of Voice Disorders, 2018 in Japan.

OBJECTIVE: To develop a summary of the first version of the Clinical Practice Guideline of Voice Disorders for Diagnosis, Management, and Treatment in Japan by the Clinical Practice Guideline Committee of the Japan Society of Logopedics and Phoniatrics and The Japan Laryngological Association. The 2018 recommendations, based on a review of the scientific literature, are intended to serve as clinical practice guidelines for the diagnosis, management, and treatment of voice disorders in Japan. METHODS: A summary of the original version of the Clinical Practice Guideline of Voice Disorders for Diagnosis, Management, and Treatment in Japan was described. Recommendations for the diagnosis, management, and treatment of voice disorders were prepared. Twelve clinical questions (CQs) regarding the diagnosis, management, treatment, and effectiveness of therapy for voice disorders were also prepared. RESULTS: A summary of the first version of the clinical practice guidelines for the diagnosis, management, and therapy of voice disorders was prepared and is presented. Additionally, answers to the 12 CQs on the diagnosis, management, treatment, and effectiveness of voice disorder therapy were prepared, and include evidence-based recommendations. CONCLUSION: These guidelines present a summary of the standard approaches for the diagnosis and treatment of voice disorders and relevant CQs that consider the medical environments in Japan. We hope that the guidelines will assist physicians in clinical settings for patients with voice disorders.

Low-risk assessment of swallowing impairment using flexible endoscopy without food or liquid.

OBJECTIVES/HYPOTHESIS: Flexible endoscopic evaluation of swallowing (FEES) is a relatively safe procedure to determine the safety of oral feeding, and consists of the introduction of food and liquid as well as a sensitivity test. However, the introduction of food and liquid can cause pneumonia or suffocation secondary to aspiration. To solve this problem, we investigated the possibility of performing FEES without introduction of food or liquid (referred to hereafter as FEES screen) to assess swallowing impairment severity. STUDY DESIGN: Retrospective study. METHODS: A total of 106 subjects with swallowing impairment underwent conventional FEES, and both their salivary pooling degree and larynx sensitivity were analyzed to detect swallowing impairment without the introduction of food or liquid. The subjects were divided into two groups: an undetectable swallowing impairment (USI) group and a detectable swallowing impairment (DSI) group. The general characteristics, functional impairment status, and clinical assistance requirements of the two groups were investigated and compared. RESULTS: The numbers of subjects in the USI and DSI groups were 64 and 42, respectively. The DSI group showed a significantly higher prevalence of aspiration during FEES, and their required levels of care were also significantly higher. Additionally, their levels of consciousness, oral intake ability, and activities of daily living were significantly low compared to the USI group. CONCLUSIONS: This study demonstrated the feasibility of FEES screen for assessment of swallowing impairment severity. Using our low-risk assessment, we were able to identify subjects with low oral intake ability as well as those who required intervention. LEVEL OF EVIDENCE: 4 Laryngoscope, 129:2249-2252, 2019.

Implantation of Induced Pluripotent Stem Cell-Derived Tracheal Epithelial Cells.

OBJECTIVES: Compared with using autologous tissue, the use of artificial materials in the regeneration of tracheal defects is minimally invasive. However, this technique requires early epithelialization on the inner side of the artificial trachea. After differentiation from induced pluripotent stem cells (iPSCs), tracheal epithelial tissues may be used to produce artificial tracheas. Herein, we aimed to demonstrate that after differentiation from fluorescent protein-labeled iPSCs, tracheal epithelial tissues survived in nude rats with tracheal defects. METHODS: Red fluorescent tdTomato protein was electroporated into mouse iPSCs to produce tdTomato-labeled iPSCs. Embryoid bodies derived from these iPSCs were then cultured in differentiation medium supplemented with growth factors, followed by culture on air-liquid interfaces for further differentiation into tracheal epithelium. The cells were implanted with artificial tracheas into nude rats with tracheal defects on day 26 of cultivation. On day 7 after implantation, the tracheas were exposed and examined histologically. RESULTS: Tracheal epithelial tissue derived from tdTomato-labeled iPSCs survived in the tracheal defects. Moreover, immunochemical analyses showed that differentiated tissues had epithelial structures similar to those of proximal tracheal tissues. CONCLUSIONS: After differentiation from iPSCs, tracheal epithelial tissues survived in rat bodies, warranting the use of iPSCs for epithelial regeneration in tracheal defects.

Retention of Human-Induced Pluripotent Stem Cells (hiPS) With Injectable HA Hydrogels for Vocal Fold Engineering.

OBJECTIVE: One prospective treatment option for vocal fold scarring is regeneration with an engineered scaffold containing induced pluripotent stem cells (iPS). In the present study, we investigated the feasibility of utilizing an injectable hyaluronic acid (HA) scaffold encapsulated with human-iPS cell (hiPS) for regeneration of vocal folds. METHODS: Thirty athymic nude rats underwent unilateral vocal fold injury. Contralateral vocal folds served as uninjured controls. Hyaluronic acid hydrogel scaffold, HA hydrogel scaffold containing hiPS, and HA hydrogel scaffold containing hiPS with epidermal growth factor (EGF) were injected in both vocal folds immediately after surgery. One and 2 weeks after injection, larynges were excised for histology, immunohistochemistry, and fluorescence in situ hybridization (FISH). RESULTS: Presence of HA hydrogel was confirmed in vocal folds 1 and 2 weeks post injection. The FISH analysis confirmed the presence and viability of hiPS in the injected vocal folds. Histological results demonstrated that vocal folds injected with HA hydrogel scaffold containing EGF demonstrated less fibrosis than those with HA hydrogel only. CONCLUSIONS: Human-iPS survived in injured rat vocal folds. The HA hydrogel with hiPS and EGF ameliorated the fibrotic response. Additional work is necessary to optimize hiPS differentiation and further confirm the safety of hiPS for clinical applications.

Effectiveness of steroid injections for bamboo nodules: A case report.

Vocal nodules are generally caused by vocal abuse, and conservative treatments such as voice therapy have been advocated as a first-choice treatment for vocal nodules. Reports of vocal fold lesions related to autoimmune diseases, such as bamboo nodules, are rare in the literature. Here we report a very rare case of bamboo nodules in a 30-year-old woman treated by steroid injection into the vocal folds by videoendoscopic laryngeal surgery in an outpatient setting. She was successfully treated without further recurrence. This report indicates that a steroid injection into bamboo nodules might be a useful treatment option, especially in patients who have not shown any improvement after conservative treatments.

Potential of laryngeal muscle regeneration using induced pluripotent stem cell-derived skeletal muscle cells.

Conclusion Induced pluripotent stem (iPS) cells may be a new potential cell source for laryngeal muscle regeneration in the treatment of vocal fold atrophy after recurrent laryngeal nerve paralysis. Objectives Unilateral vocal fold paralysis can lead to degeneration, atrophy, and loss of force of the thyroarytenoid muscle. At present, there are some treatments such as thyroplasty, arytenoid adduction, and vocal fold injection. However, such treatments cannot restore reduced mass of the thyroarytenoid muscle. iPS cells have been recognized as supplying a potential resource for cell transplantation. The aim of this study was to assess the effectiveness of the use of iPS cells for the regeneration of laryngeal muscle through the evaluation of both in vitro and in vivo experiments. Methods Skeletal muscle cells were generated from tdTomato-labeled iPS cells using embryoid body formation. Differentiation into skeletal muscle cells was analyzed by gene expression and immunocytochemistry. The tdTomato-labeled iPS cell-derived skeletal muscle cells were transplanted into the left atrophied thyroarytenoid muscle. To evaluate the engraftment of these cells after transplantation, immunohistochemistry was performed. Results The tdTomato-labeled iPS cells were successfully differentiated into skeletal muscle cells through an in vitro experiment. These cells survived in the atrophied thyroarytenoid muscle after transplantation.