Diagnostic utility of spirometry for children with induced laryngeal obstruction or chronic non-specific cough.

PURPOSE: To determine the diagnostic utility of spirometry in distinguishing children with Induced Laryngeal Obstruction (ILO) or chronic non-specific cough (a.k.a. tic cough) from those with mild or moderate to severe asthma. METHODS: Retrospective cross sectional design. Children diagnosed with ILO (N = 70), chronic non-specific cough (N = 70), mild asthma (N = 60), or moderate to severe asthma (N = 60) were identified from the electronic medical record of a large children's hospital. Spirometry was completed before ILO, non-specific cough, or asthma diagnoses were made by pediatric laryngologists or pulmonologists. Spirometry was performed following American Thoracic Society guidelines and was interpreted by a pediatric pulmonologist. Forced Vital Capacity (FVC), Forced Expiratory Volume in 1 Second (FEV1), FEV1/FVC Ratio (FEV1/FVC), Forced Mid-Expiratory Flow 25--75 % (FEF25-75%), pulmonologist interpretation of flow volume loops, and overall exam findings were extracted from the medical record. RESULTS: Ninety seven percent of children with ILO or chronic non-specific cough presented with spirometry values within normative range. Patients with ILO, non-specific cough, and mild asthma presented with FVC, FEV1, FEV1/FVC, and FEF25-75% values in statistically similar range. Children with moderate to severe asthma presented with significantly reduced FVC (p < .001), FEV1 (p < .001), FEV1/FVC (p < .001), and FEF25-75% (p < .001) values when compared with patients in the other groups. Flow volume loops were predominantly normal for children with ILO and non-specific cough. CONCLUSIONS: Findings indicate that ILO and chronic non-specific cough can neither be diagnosed nor differentiated from mild asthma using spirometry alone. Spirometry should therefore be used judiciously with this population, bearing in mind the limitations of the procedure. Future research should determine the most effective and efficient ways of delineating ILO and non-specific cough from other respiratory conditions in children.

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.

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.

Development and validation of the Exercise-Induced Laryngeal Obstruction Dyspnea Index (EILODI).

BACKGROUND: Exercise-induced laryngeal obstruction (EILO) causes exertional dyspnea and is important for its effect on quality of life, diagnostic confusion with exercise-induced asthma, and health care resource utilization. There is no validated patient-reported outcome measure specific to EILO. OBJECTIVE: We sought to develop, validate, and define a minimal clinically important difference for a patient-reported outcome measure to be used with adolescents and young adults with EILO. METHODS: A multidisciplinary group created a preliminary measure, modified by a 10-member participant focus group, with 20 items scored along a 5-point Likert scale. A subsequent cohort of participants recruited from a clinic, aged 12 to 21 years, with confirmed EILO by continuous laryngoscopy during exercise testing (1) completed the measure at 3 points in time over 28 days and (2) provided anchoring data in the form of a daily exercise log and categorical self-assessments of clinical improvement. Thirty additional participants without exertional dyspnea served as controls. RESULTS: Two hundred nineteen subjects with mild to severe EILO participated in the exploratory factor analysis, which identified 7 factors within the preliminary outcome measure. After a process of item reduction, a 12-item metric with a total score ranging from 0 to 48 was developed. Mean scores of patients with EILO and healthy controls at baseline were 28.8 ± 7.4 and 4.5 ± 7.4, respectively. A minimal clinically important difference of 6 was determined by comparison of index change with changes in categorical self-assessments of improvement. CONCLUSIONS: This is the first patient-reported outcome measure specifically designed for adolescents and young adults with EILO.

The Association between Paradoxical Vocal Fold Motion and Dysphonia in Adolescents.

OBJECTIVE: Associations between dysphonia and paradoxical vocal fold motion (PVFM) have been previously reported in adults, but it is unclear whether similar associations exist for adolescents. The goals of this study were to identify the prevalence and severity of voice disorders in adolescent patients with PVFM, identify differences between those with and without clinician-identified dysphonia, and investigate what factors were associated with voice handicap in this population. METHODS: A retrospective review of eligible adolescent patients diagnosed with PVFM over a 1-year period at a single institution was undertaken. Data collected from the medical record included demographic background, medical history and workup, patient- and family-reported symptoms, and findings from the laryngeal examination. The presence or absence of clinician-diagnosed dysphonia was used to subdivide the sample for analysis. RESULTS: Forty-eight patients with PVFM were included. The sample was primarily female (73%) with a median age of 15 years. Few patients had voice complaints (5%), but clinician-diagnosed dysphonia was common (52%) and ranged from mild to moderate. Vocal hyperfunction was frequently observed (55%), but anatomic abnormalities associated with dysphonia were rare (6%). Adolescents with dysphonia were significantly older, more likely to have vocal hyperfunction on laryngoscopy, and more likely to return for therapy than those without dysphonia. No notable differences existed in the number of behavioral therapy sessions or in the likelihood of completing treatment between the two groups. The majority of participants (79%) had at least one "confounding factor" (i.e., were currently taking a medication for asthma, allergies, or reflux, or had a laryngeal abnormality) but this did not differ significantly between those with and without dysphonia. A minority of individuals (28%) had abnormal scores on the Voice Handicap Index (VHI). Age was positively correlated with dysphonia severity but no other significant associations were observed. CONCLUSION: Although voice complaints are rare, dysphonia among adolescents with PVFM is common and can occur in the absence of laryngeal abnormalities and medical comorbidities, typically as a result of vocal hyperfunction. Dysphonia does not appear to be a barrier to PVFM treatment and may be a useful target in therapy.

Environmental Exposures and Asthma in Active Duty Service Members.

PURPOSE OF REVIEW: Reports of respiratory symptoms, including asthma and hyper-reactive airway disease, have been more numerous in the media and medical literature since active duty service members (SM) began to support campaigns in South West Asia (SWA). Numerous environmental exposures have been reported and this review assesses the available evidence surrounding exposures, confounding conditions, and attempts to develop screening mechanisms. RECENT FINDINGS: While particulate matter exposures and particularly exposure to burn pits have garnered much attention, a 2010 Armed Forces Health Surveillance Center report and 2011 Institute of Medicine publication did not identify a link between exposure to particulate matter with SM respiratory disease. The "Study of Active Duty Military for Pulmonary Disease related to Environmental Deployment Exposure," (STAMPEDE) and STAMPEDE II have not identified effective forms of routine screening and these and other sources point to the importance of other factors in SM respiratory disease. These include higher than anticipated rates of tobacco use in deployed settings, impacts of obesity, recurrence of childhood asthma, and of confounding conditions such as Paradoxical Vocal Fold Motion. As with the general population, a complex set of clinical inputs and environmental exposures surround asthma and similar respiratory processes in SM. Concrete relationships and mechanisms for assessment continue to be assessed and refined, but clear associations and pathways have remained elusive.

Diagnosis of concomitant inducible laryngeal obstruction and asthma.

BACKGROUND: Inducible laryngeal obstruction, an induced, inappropriate narrowing of the larynx, leading to symptomatic upper airway obstruction, can coexist with asthma. Accurate classification has been challenging because of overlapping symptoms and the absence of sensitive diagnostic criteria for either condition. OBJECTIVE: To evaluate patients with concomitant clinical suspicion for inducible laryngeal obstruction and asthma. We used a multidisciplinary protocol incorporating objective diagnostic criteria to determine whether asthma, inducible laryngeal obstruction, both, or neither diagnosis was present. METHODS: Consecutive patients were prospectively assessed by a laryngologist, speech pathologist and respiratory physician. Inducible laryngeal obstruction was diagnosed by visualizing paradoxical vocal fold motion either at baseline or following mannitol provocation. Asthma was diagnosed by physician assessment with objective variable airflow obstruction. Validated questionnaires for laryngeal dysfunction and relevant comorbidities were administered. RESULTS: Of 69 patients, 15 had asthma alone, 11 had inducible laryngeal obstruction alone and 14 had neither objectively demonstrated. Twenty-nine patients had both diagnoses. In 19 patients, inducible laryngeal obstruction was only seen following provocation. Among patients with inducible laryngeal obstruction, chest tightness was more frequent with concurrent asthma. Among patients with asthma, stridor was more frequent with concurrent inducible laryngeal obstruction. Cough was more frequently found in asthma alone, whereas difficulty with inspiration and symptoms triggered by psychological stress were more frequently found in inducible laryngeal obstruction alone. Patients with asthma alone had greater airflow obstruction. Relevant comorbidities were frequent (rhinitis in 85%, gastro-oesophageal reflux in 65%), and questionnaire scores for laryngeal dysfunction were abnormal. However, neither comorbidities nor questionnaires differentiated patients with or without inducible laryngeal obstruction. CONCLUSIONS AND CLINICAL RELEVANCE: In this cohort with suspected inducible laryngeal obstruction and asthma, 42% had objective evidence of both conditions. Clinical assessment, questionnaire scores and comorbidity burden were not sufficiently discriminatory for diagnosis, highlighting the necessity of objective diagnostic testing.

Functional Outcomes after Behavioral Treatment of Paradoxical Vocal Fold Motion in Adults.

OBJECTIVE: Paradoxical vocal fold motion (PVFM) is responsive to behavioral therapy, often resulting in a remission of symptoms, but little is known about whether treatment is beneficial with regard to PVFM-associated psychological symptoms or functional limitations. The goal of the study was to identify patient perceptions of the impact of treatment for PVFM and characteristics associated with treatment outcomes. METHODS: A survey was conducted of all adults who had received at least 1 session of treatment for PVFM in our outpatient clinic over a 2-year period. RESULTS: The 39 participants ranged in age from 18 to 82 and had received a median of 3 treatment sessions. At a median follow-up of 10 months following treatment, respondents reported improvements in a wide range of areas, including sports and leisure, daily activities, and social participation. The majority reported improvements in feelings of anxiety, helplessness, and control. Poorer outcomes were associated with more severe voice symptoms, fewer treatment sessions, and needing oral steroids for asthma control. CONCLUSION: There was a reduction in a wide range of activity limitations after treatment. Feelings of control were strongly associated with positive outcomes. The therapy appeared to be equally effective for adults with exercise-induced and environmental variants of PVFM.

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.

Optimizing the Diagnosis and Management of Pediatric Inducible Laryngeal Obstruction.

BACKGROUND: Pediatric inducible laryngeal obstruction (ILO) is difficult to diagnose and treat. Patients often undergo multiple specialist referrals, and long-term outcomes are not well reported. OBJECTIVES: To investigate the patterns of presentation, workup, and management of children who were diagnosed with ILO at the Stollery Children's Hospital. METHODS: Retrospective review with a prospective cohort of pediatric patients diagnosed with ILO from 2015 to 2023. We collected the demographic data, diagnostic tests, specialist referrals, time to diagnosis, symptom burden, associated comorbidities and aggravating factors, management, and treatment outcomes. A subset of patients was followed prospectively to determine treatment outcomes. A basic descriptive analysis was performed, and factors associated with time to resolution were studied. RESULTS: Seventy-eight patients met the criteria for inclusion, with 22 completing prospective questionnaires. The average age was 14 years old, and 75% were female. The majority required multiple specialist referrals. The majority were associated with exercise. Thirty-two (41%) patients had a presumed diagnosis of asthma, despite only four pulmonary function tests being consistent with asthma. Abortive breathing exercises were the most commonly employed (95%) and most successful (61%) nonsurgical management technique. Surgery was highly successful in a small cohort of patients. Median time to symptom resolution was 12 months, with 36% reporting symptoms persistent beyond 3 years. CONCLUSIONS: Pediatric ILO often goes undiagnosed for prolonged periods. Exercise-related symptoms are the most common. Management strategies have varied levels of success and a large proportion of patients have prolonged symptoms despite treatment, as supported by other recent evidence. LEVEL OF EVIDENCE: 3 Laryngoscope, 2024.

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

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

Multi-Institutional Study of Patient-Reported Outcomes of Paradoxical Vocal Fold Motion.

OBJECTIVE: To explore patient-reported outcome measures of pediatric paradoxical vocal fold motion through a multi-institutional study of geographically diverse United States medical facilities to assess long-term management and outcomes. METHODS: Eligible participants >8 years of age diagnosed with PVFM over a 10-year period from 7 tertiary pediatric hospitals were invited to complete a survey addressing study objectives. RESULTS: 65 participants completed the survey, of whom 80% were female, 75% reported a 3.5 grade point average or better, and 75% identified as competitive athletes or extremely athletic individuals. Participants rated their perceived efficacy of 13 specific treatments. Only five treatments were considered effective by a majority of the participants who tried them. The treatments that participants tried most often were breathing exercises (89.2%), bronchodilator treatments (45%), and allergy medications (35.4%). 78.8% of participants reported receiving more than one treatment and 25% reported receiving a combination of bronchodilators, anticholinergics, and steroids. At the time of PVFM diagnosis, 38% of participants had no idea when their symptoms would completely resolve. 23.3% of participants did not experience symptom resolution until greater than 1 year after diagnosis. CONCLUSIONS: Traditional management tools such as breathing exercises and biofeedback treatments may not provide the long-term benefit that providers anticipate. In addition to these commonly used management strategies, highly efficacious techniques such as counseling and lifestyle management should be incorporated into the long-term management of patients whose symptoms are refractory to traditional care. LEVEL OF EVIDENCE: 4 Laryngoscope, 133:970-976, 2023.

Examining the Influence of Chemosensation on Laryngeal Health and Disorders.

Inhaled airborne stimuli are associated with laryngeal disorders affecting respiration. Clinically, several themes emerged from the literature that point to specific gaps in the understanding and management of these disorders. There is wide variation in the types of airborne stimuli that trigger symptoms, lack of standardization in provocation challenge testing using airborne stimuli, and vague reporting of laryngeal symptoms. Scientifically, evidence exists outside the field of voice science that could prove useful to implement among patients with impaired laryngeal-respiration. To expand this area of expertise, here we provide a thematic overview of relevant evidence and methodological tools from the discipline of chemosensory sciences. This review provides distinctions across the three chemosensory systems of olfaction, trigeminal chemesthesis, and gustation, guidance on selecting and delivering common chemosensory stimuli for clinical testing, and methods of quantifying sensory experiences using principles of human psychophysics. Investigating the science of chemosensation reveals that laryngeal responses to inhaled airborne stimuli have explanations involving physiological mechanisms as well as higher cognitive processing. Fortunately, these findings are consistent with current pharmacological and nonpharmacological interventions for impaired laryngeal-respiration. Based on the close relationships among inhaled airborne stimuli, respiration, and laryngeal function, we propose that new perspectives from chemosensory sciences offer opportunities to improve patient care and target areas of future research.

A Case of "Anaphylaxis" to NovoSeven in a Hemophiliac Patient.

Anaphylaxis is a life-threatening emergency that may be confused with other less serious conditions. The onset of true anaphylaxis typically occurs within minutes following exposure to an offending agent, and it can variably include dyspnea/wheezing, hemodynamic compromise, rash, hives/pruritus, swelling, or gastrointestinal symptoms. The absence of an expected association between exposure(s) and classic symptoms should lead to the consideration of alternative diagnoses. Here, we describe the course of a patient with hemophilia B who developed stridor and wheezing after exposure to the recombinant factor VII, NovoSeven, and tranexamic acid (TXA) for the management of hematomas. Due to a reported prior history of anaphylaxis to multiple factor replacements, the patient's initial management included NovoSeven with steroid/antihistamine prophylaxes and close monitoring with epinephrine at the bedside. Despite the administration of prophylaxis, the patient developed significant stridor, was treated with epinephrine and nebulizers and additional steroids, and was transferred to the intensive care unit. There, a pattern of NovoSeven administration followed variably by wheezing and stridor continued for two days until the patient's respiratory condition was predictable and stable. The patient's subsequent clinical course following transfer to the general medical ward was not consistent with anaphylaxis. This case highlights the importance of evaluating for mimickers of anaphylaxis, especially where only select symptoms such as stridor and wheezing are present without other serious signs of anaphylaxis such as hypoxemia, hypotension, or significant tachycardia.

Computational fluid dynamics of upper airway aerodynamics for exercise-induced laryngeal obstruction: A feasibility study.

Objective: Use of computational fluid dynamic (CFD) simulations to measure the changes in upper airway geometry and aerodynamics during (a) an episode of Exercise-Induced Laryngeal Obstruction (EILO) and (b) speech therapy exercises commonly employed for patients with EILO. Methods: Magnetic resonance imaging stills of the upper airway including the nasal and oral cavities from an adult female were used to re-construct three-dimensional geometries of the upper airway. The CFD simulations were used to compute the maximum volume flow rate (l/s), pressure (Pa), airflow velocity (m/s) and area of cross-section opening in eight planes along the vocal tract, separately for inhalation and exhalation. Results: Numerical predictions from three-dimensional geometrical modeling of the upper airway suggest that the technique of nose breathing for inhalation and pursed lip breathing for exhalation show most promising pressure conditions and cross-sectional diameters for rescue breathing exercises. Also, if EILO is due to the constriction at the vocal fold level, then a quick sniff may also be a proper rescue inhalation exercise. EILO affects both the inspiratory and the expiratory phases of breathing. Conclusions: A prior knowledge of the supraglottal aerodynamics and the corresponding upper airway geometry from CFD analysis has the potential to assist the clinician in choosing the most effective rescue breathing technique for optimal functional outcome of speech therapy intervention in patients with EILO and in understanding the pathophysiology of EILO on a case-by-case basis with future studies. Level of Evidence: 4.

The impact of a fast-track questionnaire in pediatric paradoxical vocal fold motion disorder (PVFMD).

OBJECTIVE: PVFMD is a frequent cause of dyspnea in the healthy adolescent. When PVFMD is suspected, the current standard of care includes referral to an otolaryngologist (ENT) prior to beginning laryngeal control therapy (LCT) with a speech language pathologist (SLP). We hypothesize that a "fast-track" screening questionnaire will improve time to treatment and decrease patient charges. METHODS: Patients (n = 258, group 1) who received traditional referral and were evaluated in pediatric voice clinic with a diagnosis of PVFMD between 11/2013 and 11/2017 were identified and compared with 66 patients (group 2) from 10/2018 to 11/2019 who were prospectively studied and placed into a fast-tracked subgroup for LCT without preceding ENT evaluation if they scored 8/10 or higher on a designed screening questionnaire. RESULTS: Female gender (group 1: 81%, group 2: 83%, p = 0.73) and median age (group 1:14 years IQR 4; group 2:14 years IQR 3, p = 0.83) were similar. The median duration from symptom onset to LCT was shorter for group 2 (group 1: 12 months, IQR 18; group 2: 8.5 months, IQR 8)(p = 0.02). Time from referral to LCT was shorter for group 2 at 3 weeks (IQR 3) compared to group 1 at 4 weeks (IQR 3.5, p < 0.01). The minimum single patient charge for group 1 was estimated at $5123 and $1649 for group 2, yielding a potential reduction of charges of over $3000. CONCLUSION: Using a fast-track screening questionnaire for pediatric PVFMD patients significantly decreases the time to treatment without altering the response rate of LCT.

Clinical presentation of paradoxical vocal fold motion or laryngeal dyskinesia in infants.

OBJECTIVES: Paradoxical vocal fold motion (PVFM) is not well-characterized in infants. Sex- and race/ethnicity-based differences have been described in older children with PVFM. This study's objectives are to characterize demographic and clinical characteristics of infants diagnosed with PVFM and investigate sex- and race-specific differences in presentation. METHODS: We retrospectively reviewed infants ≤1 year of age diagnosed with PVFM at our institution from 2009 to 2019. Patient demographics, symptoms, and findings on flexible laryngoscopy are described. Sex- and race/ethnicity-based differences were assessed using Fisher's exact test analyses. RESULTS: We identified 22 infants who were diagnosed with PVFM. The average age (range) at diagnosis was 5.7 (0.25-12.0) months, and 45.5% were male. The majority (54.6%) of patients identified as non-Hispanic White. Common comorbidities included GERD (45.5%) and chronic rhinitis (13.6%). Stridor was the only presenting symptom in the majority of patients (95.4%). The most common episode triggers were crying (45.5%), feeding (27.3%), and gastric reflux (9.1%). On flexible laryngoscopy, PVFM was observed in 95.5% of patients. A third of patients (31.8%) were misdiagnosed as having reactive airway disease or laryngomalacia prior to evaluation by otolaryngology. No sex- and race/ethnicity-based differences in presentation were identified. CONCLUSION: We present the largest case series of PVFM in infants. We found sparse clinical signs/symptoms other than stridor and a high incidence of misdiagnosis, which supports the importance of objective flexible laryngoscopy for the evaluation of stridor in this age group. Previously reported sex- and race/ethnicity-based differences in presentation of PVFM were not observed in this cohort of infants.

Repetitive Transcranial Magnetic Stimulation, a Novel Therapeutic Strategy for Refractory Paradoxical Vocal Fold Motion Disorder.

Paradoxical vocal fold motion disorder (PVFMD) is a condition involving the inappropriate narrowing of the larynx with symptoms of laryngeal tightness and dyspnea. A 23-year-old woman was diagnosed with PVFMD by imaging, revealing dynamically constricted, supraglottic tissue, an abnormal adduction of the vocal cords with a characteristic "posterior chink" observed. After diagnosis, laryngeal control retraining protocols and biofeedback therapy were initiated. To treat persistent symptoms, interventions such as vocal fold botulinum toxin (BoNT) injections were performed with slight improvements. Ultimately, psychiatry performed 10 repetitive transcranial magnetic stimulations (rTMS) with a right-sided, low-frequency approach to treat the patient's underlying major depressive disorder and comorbid anxious distress. Afterward, the patient's symptoms were successfully reduced with an improvement in Dyspnea Severity Index. Although most patients with PVFMD were relieved with laryngeal control therapy, some are refractory and lack the literature on the best treatment. In this case, we followed the multidisciplinary approach and individualized our novel therapeutic strategies including especially rTMS, which successfully reduced symptoms. This is the first reported case of refractory PVFMD to be treated with novel interventions, and rTMS might play a role in PVFMD mitigation.

Resting Respiratory Resistance in Female Teenage Athletes With and Without Exercise-Induced Laryngeal Obstruction.

OBJECTIVE: Exercise-induced laryngeal obstruction (EILO) occurs with paradoxical vocal fold motion or supraglottic collapse during moderate to vigorous exercise. Previously, Gallena et al (2015) reported lower-than-normal inspiratory (Ri) and expiratory (Re) resistances during resting tidal breathing (RTB) in female teenage athletes with EILO. This study aimed to replicate that unexpected result. METHOD: The Airflow Perturbation Device measured Ri and Re during three 1-minute trials of RTB in 16 teenage female athletes with EILO and 16 sex-, age-, and height-matched controls. Multiple linear regression examined group, age, height, and weight as predictors of Ri and Re. RESULTS: Ri and Re tended to be lower in the EILO group than the control group [Ri: F(1,30) = 3.58, P = 0.068, d = 0.686; Re: F(1,30) = 3.28, P = 0.080, d = 0.640], but there was no statistically significant difference in the overall effect [F(2,29) = 1.75, P = 0.192]. After one outlier for Re from the EILO group and her matched control were removed, the overall difference was statistically significant, F(2,27) = 3.38, P = 0.049, with Re primarily contributing to the difference [Ri: F(1,28) = 3.66, P = 0.066, d = 0.719; Re: F(1,28) = 5.69, P = 0.024, d = 0.899]. CONCLUSION: These results did not replicate the robust differences found previously between Ri and Re during RTB in teenage girls with and without EILO, but the results trended in the same direction and met criterion for statistical significance once an outlier was removed from analysis. Overall, the observation that resting respiratory resistances were lower in most teenage girls with EILO suggests that reduced tone of the laryngeal and/or lower airways may predispose young athletes to EILO.

The impact of identifying laryngeal obstruction syndromes on reducing treatment of pediatric asthma: A systematic review.

Inducible laryngeal obstruction (ILO) in children is underrecognized. This systematic review characterizes the scientific evidence on the impact of pediatric ILO diagnosis and treatment on asthma medication use. This review, registered with PROSPERO (CRD42020209168), utilized database searches in MEDLINE, EMBASE, CINAHL, and Web of Science from inception to October 2020. Both experimental and observational studies on ILO and asthma outcomes in patients ≤18 years were included. Population characteristics (sample size, sex, age, and comorbidities) and study outcomes (medication usage and respiratory symptoms) were extracted. The risk of bias was assessed with the National Toxicology Program's Office of Health Assessment and Risk of Bias Rating Tool. Data are presented narratively due to study heterogeneity. Of 1091 studies, 1076 titles and abstracts were screened after duplicate removal. Screening 31 full texts yielded eight pre-post studies. Patients were an average of 14.1 years old, 15% male, and >90% used asthma medication; 40% reported allergies, 30% gastroesophageal reflux, and 20% anxiety or depression. Most patients received at least one intervention, with 75% showing symptomatic improvement and >75% decreasing or stopping asthma medications. Studies were small with a high risk of selection, confounding, and detection bias. Asthma management was not a primary outcome in any of the studies. Overall, ILO patients were often diagnosed with or treated for asthma before ILO diagnosis. Evidence from individual studies suggests that comorbidities including ILO, gastroesophageal reflux, allergies, and anxiety should be considered in pediatric patients with asthma not responsive to medical therapy. Further research is required to determine the proportion of impacted asthma patients.