Feasibility of Constant Work Rate Testing to Detect Exercise-Induced Laryngeal Obstruction.

INTRODUCTION: Exercise-induced laryngeal obstruction (EILO) is a condition in which laryngeal structures inappropriately obstruct the upper airway during exercise. The standard diagnostic test for EILO is the continuous laryngoscopy during exercise (CLE) test, usually performed with an incremental work rate protocol regardless of the nature of the triggering event. Typically, laryngeal obstruction occurs only briefly at the end of an incremental test, near peak work capacity. We aimed to investigate constant work rate (CWR) protocols for CLE testing to expand diagnostic test modalities and improve the understanding of EILO. METHODS: In this prospective, self-controlled feasibility study, 10 patients with EILO performed both an incremental and a CWR CLE test at 70%, 80%, and 90% of maximal exercise capacity. Laryngoscopic video data were recorded and compared, and we evaluated the ability of CWR to reproduce the symptoms and laryngeal obstruction seen in incremental testing. RESULTS: In 70%-90% of cases, CWR testing induced at least the same severity of obstruction as incremental testing and CLE scores remained comparable across test modalities. CWR at 70% allowed observation of laryngeal obstruction for a significantly longer duration than in incremental testing (158 s; 95% confidence interval, 25-291 s; P = 0.027). Dyspnea intensity appeared higher during CWR testing compared with incremental testing. CONCLUSIONS: Submaximal CWR CLE testing is feasible and able to induce EILO equivalent to the standard incremental CLE test. This is the first step toward tailored CLE exercise protocols, and further studies are now needed to establish the utility of CWR in clinical and research settings.

Epiglottic retroversion as a cause of upper airway obstruction: A case report.

RATIONALE: Epiglottic retroversion is the abnormal movement of the epiglottis to the rima glottis, resulting in blockage of inspiratory airflow. Acute upper airway obstruction caused by epiglottic retroversion can lead to sudden respiratory failure. Epiglottic retroversion has occasionally been reported in horses and dogs; however it is extremely rare in humans. Herein, we report a case of epiglottic retroversion causing recurrent upper airway obstruction in human. PATIENT CONCERNS: We present the case of a 74-year-old man who was diagnosed with epiglottic retroversion without evidence of epiglottis. The patient presented with recurrent episodes of abnormal breathing sounds and dyspnea. Inspiratory stridor was evident whenever the patient experienced dyspnea. DIAGNOSIS: Epiglottic retroversion was diagnosed as the cause of upper airway obstruction using fiber-optic bronchoscopy. INTERVENTIONS: The patient underwent tracheostomy to prevent acute respiratory failure because the recurrent episodes of stridor and dyspnea did not improve. OUTCOMES: The episodic dyspnea and oxygen desaturation did not relapse after tracheostomy and he could be discharged home. LESSONS: This case highlights the importance of considering epiglottic retroversion as a cause of acute upper airway obstruction.

Are Questionnaires Helpful To Predict Exercise-Induced Bronchoconstriction (EIB) And Exercise-Induced Laryngeal Obstruction (EILO)?

OBJECTIVE: Exercise induced laryngeal obstruction (EILO) is an important differential diagnosis to exercise induced bronchoconstriction (EIB) and diagnosed via continuous laryngoscopy while exercising (CLE). However, availability of CLE is limited to specialized centres. And without CLE EILO is often misdiagnosed as EIB. Therefore it is essential to carefully preselect potential EILO candidates. Aim of this study was to investigate whether two short questionnaires -Asthma Control Test (ACT) and Dyspnea Index (DI) evaluating upper airway-related dyspnea- can differentiate between EIB and EILO. METHODS: Patients with dyspnea while exercising were analysed with an exercise challenge in the cold chamber (ECC) to diagnose EIB in visit 1 (V1), as appropriate a CLE in visit 2 (V2, 4-6 weeks after V1) and ACT and DI in V1 and V2. EIB patients were treated with asthma medication after V1. RESULTS: Complete dataset of 36 subjects were gathered. The ACT showed lower values in V2 in EILO compared to EIB patients. A lack of improvement in ACT in V2 after asthma medication of EIB patients is suspicious for additional EILO diagnosis. The DI showed higher values in V1 in EILO compared to EIB patients. A score≥30 can predict a positive CLE reaction. CONCLUSION: ACT and DI are valuable tools in preselecting CLE candidates to assure timely diagnostic despite limited diagnostic capabilities.

Laryngoscopy-based scoring system for the diagnosis of vocal fold leukoplakia.

OBJECTIVE: To propose a scoring system based on laryngoscopic characteristics for the differential diagnosis of benign and malignant vocal fold leukoplakia. METHODS: Laryngoscopic images from 200 vocal fold leukoplakia cases were retrospectively analysed. The laryngoscopic signs of benign and malignant vocal fold leukoplakia were compared, and statistically significant features were assigned and accumulated to establish the leukoplakia finding score. RESULTS: A total of five indicators associated with malignant vocal fold leukoplakia were included to construct the leukoplakia finding score, with a possible range of 0-10 points. A score of 6 points or more was indicative of a diagnosis of malignant vocal fold leukoplakia. The sensitivity, specificity and accuracy values of the leukoplakia finding score were 93.8 per cent, 83.6 per cent and 86.0 per cent, respectively. The consistency in the leukoplakia finding score obtained by different laryngologists was strong (kappa = 0.809). CONCLUSION: This scoring system based on laryngoscopic characteristics has high diagnostic value for distinguishing benign and malignant vocal fold leukoplakia.

Clinical Profiles of Children and Adolescents With Induced Laryngeal Obstruction (ILO) and Exercise Induced Laryngeal Obstruction (EILO).

PURPOSE: To compare clinical profiles of pediatric patients with Induced Laryngeal Obstruction (ILO), Exercise Induced Laryngeal Obstruction (EILO), and EILO with non-exertion related secondary triggers (EILO+). METHODS: A retrospective observational cohort design was employed. Four-hundred and twenty-three patients <18 years of age were identified from the electronic medical record of a large children's hospital. All patients underwent evaluations with a laryngologist and speech-language pathologist and were diagnosed with EILO/ILO. Patients were divided into 3 groups based on dyspnea triggers reported in initial evaluations. Groups consisted of patients with EILO (N = 281), ILO (N = 30), and EILO+ (N = 112). Patient demographics, EILO/ILO symptoms, endoscopy findings, medical comorbidities, medical history, and EILO/ILO treatment information were extracted and compared across EILO/ILO subtypes. RESULTS: Patients with EILO experienced higher rates of hyperventilation (P < .001), sore throat (P = .023), and chest pain (P = .003). Patients with ILO were significantly younger in age (P = .017) and presented with increased rates of nighttime symptoms (P < .001), globus sensation (P = .008), self-reported reflux symptoms (P = .023), and history of gastrointestinal conditions (P = .034). Patients with EILO+ were more likely to be female (P = .037) and presented with higher prevalence of anxiety (P = .003), ADHD (P = .004), chest tightness (P = .030), and cough (P < .001). CONCLUSIONS: Patients with EILO, ILO, and EILO+ present with overlapping but unique clinical profiles. A prospective study is warranted to determine the etiology of these differences and clarify how the efficacy of EILO, ILO, and EILO+ treatment can be maximized. LEVEL OF EVIDENCE: 4.

What Are Vocal Cord Nodules?

This Patient Page describes the symptoms, diagnosis, and treatment of vocal cord nodules.

Surgical management of vocal cord nodules in children: Trends and outcomes.

OBJECTIVES: Vocal cord nodules (VCNs) are the most common cause of dysphonia in school-aged children, with potential negative impacts on quality of life including diminished self-esteem and academic performance. The standard of care for VCNs is conservative management which ranges from voice hygiene to speech therapy with a focus on voice otherwise known as voice therapy, with surgical excision reserved for refractory cases. Thus, few studies have analyzed outcomes of surgical management of VCNs. The purpose of this study is to assess the prevalence and efficacy of surgical excision of VCNs when compared to speech therapy. METHODS: Children with VCNs seen at a single tertiary care institution between 2015 and 2020 were identified by ICD-9 code 478.5 and ICD-10 code J38.2. Demographics, objective voice assessment, intervention, and follow-up assessment data were reviewed. Frequencies, medians, and interquartile ranges were calculated. Time to resolution and improvement were assessed by Cox proportional hazards model. Univariate logistic regression was performed. A P value of <0.05 was considered statistically significant. RESULTS: Three hundred sixty-eight patients diagnosed with VCNs were identified. 169 patients received intervention for VCNs, with 159 (43.2 %) receiving speech therapy alone and 5 (1.4 %) receiving surgery alone. On bivariate analysis, there was no significant difference in demographic features between treatment groups, however speech therapy patients did have a longer follow-up time. 154 patients underwent objective voice assessment at the time of VCN diagnosis. Among these patients, 95 (61.7 %) received speech therapy and 59 (40.3 %) received no intervention. Speech therapy patients had significantly higher pVHI scores, however there was no significant difference in CAPE-V Overall Severity scores or computerized voice assessment analysis. On Cox proportional hazards analysis, surgical intervention was associated with faster resolution and faster improvement of dysphonic symptoms. On binary logistic regression, surgery was associated with a significantly greater proportion of patients reporting resolution of dysphonic symptoms, however there was no significant difference in proportion of patients reporting improvement of dysphonia. CONCLUSION: For most patients with VCNs, conservative measures such as voice hygiene and speech therapy remain first line, however certain patients may benefit from the rapid improvement and resolution of symptoms that surgical intervention may provide.

Examining therapy duration in adults with induced laryngeal obstruction (ILO).

OBJECTIVE: This study examined the number of therapy sessions required to sufficiently improve (exercise) induced laryngeal obstruction (EILO/ILO) symptoms for discharge. Factors predicting therapy duration were examined as was the likelihood of patients returning for additional therapy sessions following initial discharge. METHODS: Retrospective observational cohort design. Data for 350 patients were gathered from the University of Wisconsin-Madison Voice and Swallow Clinics Outcome Database. Patients (>18 years of age) diagnosed with EILO/ILO received therapy from a Speech-Language Pathologist (SLP) and were successfully discharged. EILO/ILO treatment details, symptoms, triggers, medical comorbidities, and patient demographics were collected from initial evaluations and subsequent course of therapy. RESULTS: Patients required an average of 3.59 (SD = 3.7) therapy sessions prior to discharge. A comorbid behavioral health diagnosis (p = .026), higher Vocal Handicap Index Score (p = .009) and reduced physical activity due to EILO/ILO symptoms (p = .032) were associated with increased therapy duration. Patients with ILO or EILO with secondary environmental triggers required significantly more sessions than those with exercise-induced symptoms (p < .01). Eight percent of patients returned for additional sessions following discharge. Patients returning for additional sessions all came from affluent neighborhoods as measured by the Area Deprivation Index (ADI). CONCLUSIONS: Patients with EILO/ILO required an average of 3.59 therapy sessions prior to discharge. As such, 4 sessions is a reasonable estimate for clinicians to provide patients. Six sessions may be a more conservative estimate for patients who present with a behavioral health diagnosis, a voice complaint, or reduced physical activity from EILO/ILO symptoms.

[New progress in the surgical treatment of laryngeal cyst in infants and children].

Laryngeal cyst is a cystic lesion occurring in the laryngeal cavity. Large laryngeal cyst in infants and young children can cause laryngeal wheezing and other upper airway obstruction symptoms. In severe cases, it can be even life-threatening and requires timely surgical treatment. Currently, there is a lack of unified clinical treatment strategy for this disease.This article summarizes the surgical methods, the advantages and disadvantages of various surgical methods for laryngeal cysts in recent years. It is recommended that needle aspiration, partial cyst wall resection, radical cyst dissection, transoral robotic surgery or external approach cyst resection should be selected through full communication and evaluation to clarify the extent of the lesion scope and the advantages and disadvantages of surgery.

[Inducible laryngeal obstruction: detection and management]. / Obstruction laryngée induite : détection et prise en charge.

Inducible laryngeal obstruction (ILO) is a phenomenon of paradoxical upper airway closure during breathing causing respiratory distress and a noisy breathing. It most often appears during maximal exertion but can also be induced by inhalation of irritants, pharyngolaryngeal reflux or stressful situations. It can sometimes be confused with an acute asthma attack. The gold standard investigation is a videolaryngoscopy during ergometry which can confirm the diagnosis, allowing appropriate treatment. The aim of this article is to describe the pathophysiology of ILO and to discuss paraclinical examinations and treatment options.

L'obstruction laryngée induite (ILO) est un phénomène de fermeture paradoxale des voies aériennes supérieures pendant la respiration qui provoque une détresse respiratoire et une symptomatologie bruyante. Elle apparaît le plus souvent pendant un effort maximal mais peut aussi être liée à l'inhalation de produits irritants, à un reflux pharyngolaryngé ou au stress. Elle peut parfois être confondue avec une crise d'asthme en phase aiguë. L'examen de choix est la vidéolaryngoscopie d'effort, qui permet de confirmer le diagnostic et de choisir le traitement approprié. Le but de cet article est de décrire la physiopathologie de l'ILO et de discuter des examens paracliniques et traitements proposés.

[A case of subglottic cysts in monochorionic monoamniotic twins]. / Klinicheskoe nablyudenie razvitiya podskladkovykh kist u monokhorial'nykh monoamnioticheskikh bliznetsov.

The first observation in the world literature of the development of subglottic cysts in the larynx in monochorionic monoamniotic twins is presented. The girls were born prematurely at 34 weeks of gestation, from the first day of life for 7 and 8 days, respectively, were transferred to mechanical ventilation. At the fourth month of life, symptoms of laryngeal stenosis appeared and began to gradually progress, conservative therapy had no effect. The diagnosis of subglottic cysts was established on the basis of fibrolaryngoscopy; after endolaryngeal surgery, breathing returned to normal. This case demonstrates the importance of timely endoscopic examination of the respiratory tract in children with stridor.

A case of epiglottic entrapment in a cat.

OBJECTIVE: The objective of this study was to describe a case of epiglottic entrapment in a cat. CASE SUMMARY: A 5-month-old male neutered Russian Blue cat was evaluated for progressive stertorous upper airway sounds, acute onset vestibulopathy and abnormal laryngeal anatomy. Endotracheal intubation was only able to be achieved using videoscopic guidance and identified concern for severe nasopharyngeal stenosis. A computerized tomography scan revealed otitis interna, narrowed nasopharynx and no definitive cause for the stertorous breathing. The cat recovered very slowly from anaesthesia due to concern for airway obstruction following extubation. It was discharged the following day and then passed away at home 2 weeks later. Necropsy revealed that the epiglottis was obscured by 2 cm of redundant mucosal tissue extending from the base of the tongue to the larynx resulting in epiglottic entrapment. Also noted was chronic, severe otitis interna and externa. Upper airway obstruction is suspected to be the cause of sudden death. NEW OR UNIQUE INFORMATION: To the authors' knowledge, this is the first report of these oropharyngeal anatomic abnormalities in a cat.

Prevalence and impact of exercise-induced laryngeal obstruction in asthma: a study protocol for a cross-sectional and longitudinal study.

INTRODUCTION: Exercise-induced laryngeal obstruction (EILO) and exercise-induced asthma can cause troublesome respiratory symptoms that can be difficult to distinguish between. Further, there is now a growing appreciation that the two conditions may coexist, complicating the interpretation of symptoms. The primary aim of this study is to investigate the prevalence of EILO in patients with asthma. Secondary aims include evaluation of EILO treatment effects and investigation of comorbid conditions other than EILO in patients with asthma. METHODS AND ANALYSIS: The study will be conducted at Haukeland University Hospital and Voss Hospital in Western Norway, and enrol 80-120 patients with asthma and a control group of 40 patients without asthma. Recruitment started in November 2020, and data sampling will continue until March 2024. Laryngeal function will be assessed at baseline and at a 1-year follow-up, using continuous laryngoscopy during high-intensity exercise (CLE). Immediately after the EILO diagnosis is verified, patients will be treated with standardised breathing advice guided by visual biofeedback from the laryngoscope video screen. The primary outcome will be the prevalence of EILO in patients with asthma and control participants. Secondary outcomes include changes in CLE scores, asthma-related quality of life, asthma control and number of the asthma exacerbations, as assessed between baseline and the 1-year follow-up. ETHICS AND DISSEMINATION: Ethical approval has been obtained from the Regional Committee for Medical and Health Research Ethics, Western Norway, (ID number 97615). All participants will provide signed informed consent before enrolment. The results will be presented in international journals and conferences. TRIAL REGISTRATION NUMBER: NCT04593394.

Difficult endotracheal intubation due to a large epiglottic cyst: A case report.

RATIONALE: An epiglottic cyst is a type of benign tumor that is formed due to the obstruction of the mucinous duct and the retention of glandular secretion. In such cases, the glottis is not visible as it is covered by the enlarged epiglottic cyst. When conventional anesthesia is administered in such patients, they might have difficulty ventilation since the epiglottic cyst can easily form a flap and move with external pressure changes and can cause the blockage of the glottis due to the loss of consciousness and the relaxation of the throat muscles of the patient. If endotracheal intubation is not initiated and effective ventilation is not established, the patient may suffer from hypoxia and other accidents. PATIENT CONCERNS: A 48-year-old male presented to the otolaryngology department with a foreign body sensation in the throat. DIAGNOSES: A large epiglottic cyst was diagnosed. INTERVENTIONS: The patient was planned to undergo epiglottis cystectomy under general anesthesia. After induction of anesthesia, the cyst severely covered the glottis and made endotracheal intubation difficult. The anesthesiologist rapidly adjusted the position of the laryngeal lens; thus, the endotracheal intubation was successful under the visual laryngoscope. OUTCOMES: The endotracheal intubation was successful under the visual laryngoscope and the operation went well. LESSONS: Patients with epiglottic cysts are more likely to have difficult airways after induction of anesthesia. Anesthesiologists should take preoperative airway assessment seriously, efficiently handle difficult airway and intubation failure, and make quick and correct choices to ensure patient safety.

Diagnosis of vocal cord dysfunction/inducible laryngeal obstruction: An International Delphi Consensus Study.

BACKGROUND: Vocal cord dysfunction/inducible laryngeal obstruction (VCD/ILO) is characterized by breathing difficulties in association with excessive supraglottic or glottic laryngeal narrowing. The condition is common and can occur independently; however, it may also be comorbid with other disorders or mimic them. Presentations span multiple specialties and misdiagnosis or delayed diagnosis is commonplace. Group-consensus methods can efficiently generate internationally accepted diagnostic criteria and descriptions to increase clinical recognition, enhance clinical service availability, and catalyze research. OBJECTIVES: We sought to establish consensus-based diagnostic criteria and methods for VCD/ILO. METHODS: We performed a modified 2-round Delphi study between December 7, 2021, and March 14, 2022. The study was registered at ANZCTR (Australian New Zealand Clinical Trials Registry; ACTRN12621001520820p). In round 1, experts provided open-ended statements that were categorized, deduplicated, and amended for clarity. These were presented to experts for agreement ranking in round 2, with consensus defined as ≥70% agreement. RESULTS: Both rounds were completed by 47 international experts. In round 1, 1102 qualitative responses were received. Of the 200 statements presented to experts across 2 rounds, 130 (65%) reached consensus. Results were discussed at 2 international subject-specific conferences in June 2022. Experts agreed on a diagnostic definition for VCD/ILO and endorsed the concept of VCD/ILO phenotypes and clinical descriptions. The panel agreed that laryngoscopy with provocation is the gold standard for diagnosis and that ≥50% laryngeal closure on inspiration or Maat grade ≥2 define abnormal laryngeal closure indicative of VCD/ILO. CONCLUSIONS: This Delphi study reached consensus on multiple aspects of VCD/ILO diagnosis and can inform clinical practice and facilitate research.

Exercise induced laryngeal obstruction (EILO) in children and young people: Approaches to assessment and management.

Exercise Induced Laryngeal Obstruction (EILO) is characterised by breathlessness, cough and/or noisy breathing particularly during high intensity exercise. EILO is a subcategory of inducible laryngeal obstruction where exercise is the trigger that provokes inappropriate transient glottic or supraglottic narrowing. It is a common condition affecting 5.7-7.5% of the general population and is a key differential diagnosis for young athletes presenting with exercise related dyspnoea where prevalence rates go as high as 34%. Although the condition has been recognised for a long time, little attention, and awareness of the condition results in many young people dropping out of sporting participation due to troublesome symptoms. With evolving understanding of the condition, diagnostic tests and interventions, this review looks to present the current available evidence and best practice when managing young people with EILO.

Vocal cord dysfunction/inducible laryngeal obstruction: novel diagnostics and therapeutics.

INTRODUCTION: Vocal cord dysfunction/inducible laryngeal obstruction (VCD/ILO) is an important medical condition but understanding of the condition is imperfect. It occurs in healthy people but often co-exists with asthma. Models of VCD/ILO pathophysiology highlight predisposing factors rather than specific mechanisms and disease expression varies between people, which is seldom appreciated. Diagnosis is often delayed, and the treatment is not evidence based. AREAS COVERED: A unified pathophysiological model and disease phenotypes have been proposed. Diagnosis is conventionally made by laryngoscopy during inspiration with vocal cord narrowing >50% Recently, dynamic CT larynx was shown to have high specificity (>80%) with potential as a noninvasive, swift, and quantifiable diagnostic modality. Treatment entails laryngeal retraining with speech pathology intervention and experimental therapies such as botulinum toxin injection. Multidisciplinary team (MDT) clinics are a novel innovation with demonstrated benefits including accurate diagnosis, selection of appropriate treatment, and reductions in oral corticosteroid exposure. EXPERT OPINION: Delayed diagnosis of VCD/ILO is pervasive, often leading to detrimental treatments. Phenotypes require validation and CT larynx can reduce the necessity for laryngoscopy, thereby fast-tracking diagnosis. MDT clinics can optimize management. Randomized controlled trials are essential to validate speech pathology intervention and other treatment modalities and to establish international standards of care.

Vocal cord dysfunction/inducible laryngeal obstruction-2022 Melbourne Roundtable Report.

Vocal cord dysfunction/inducible laryngeal obstruction (VCD/ILO), is a common condition characterized by breathlessness associated with inappropriate laryngeal narrowing. Important questions remain unresolved, and to improve collaboration and harmonization in the field, we convened an international Roundtable conference on VCD/ILO in Melbourne, Australia. The aims were to delineate a consistent approach to VCD/ILO diagnosis, appraise disease pathogenesis, outline current management and model(s) of care and identify key research questions. This report summarizes discussions, frames key questions and details recommendations. Participants discussed clinical, research and conceptual advances in the context of recent evidence. The condition presents in a heterogenous manner, and diagnosis is often delayed. Definitive diagnosis of VCD/ILO conventionally utilizes laryngoscopy demonstrating inspiratory vocal fold narrowing >50%. Computed tomography of the larynx is a new technology with potential for swift diagnosis that requires validation in clinical pathways. Disease pathogenesis and multimorbidity interactions are complex reflecting a multi-factorial, complex condition, with no single overarching disease mechanism. Currently there is no evidence-based standard of care since randomized trials for treatment are non-existent. Recent multidisciplinary models of care need to be clearly articulated and prospectively investigated. Patient impact and healthcare utilization can be formidable but have largely escaped inquiry and patient perspectives have not been explored. Roundtable participants expressed optimism as collective understanding of this complex condition evolves. The Melbourne VCD/ILO Roundtable 2022 identified clear priorities and future directions for this impactful condition.

Update on the pediatric adverse vocal behavior voice disorders: a clinical practice review.

The main causes of voice disorders in children with adverse vocal behavior include benign lesions of the vocal folds caused by voice abuse or misuses, such as vocal fold nodules, vocal fold polyps, and laryngitis. Long-term voice disorders can affect the physical and mental health of children. Reviewing the literature of the last two decades on "Vocal Fold Nodules," "Vocal Fold Polyp," "Voice disorder," "Voice Abuse," "Voice Misuse," "Pediatrics," and "Children" with the appropriate Boolean operators.  Conclusion: A total of 315 results were returned on an initial PubMed search. All articles from 2000 to 2022 written in English or Chinese were screened. Duplicate articles, those relating to adults only or concerned with the malignant lesion of the vocal cord, were excluded, resulting in 196 articles of interest. Relevant references and books have also been consulted, and we provide a review of the pathogenesis, diagnosis, and treatment of these maladaptive vocal behavioral voice disorders. What is Known: • Hoarseness is the most common voice symptom in children, and there are various causes of hoarseness in children. However, there is a lack of reviews on voice disorders caused by adverse vocal habits in children. • Voice training is a conservative treatment method for children with voice disorders , and it is important to clarify the factors that influence the effectiveness of voice training for children. What is New: • This review of the personality and family characteristics of children with adverse vocal behavioural voice disorders provides a valuable guide to the clinical planning of subsequent treatment. • This article discusses and summarises some of the factors that may influence the effectiveness of voice training in children and collates some of the scales and questionnaires currently used in children that are important in predicting the effectiveness of voice training.