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.

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.

Long-Term Outcomes of Respiratory Retraining Therapy for Exercise-Induced Laryngeal Obstruction

OBJECTIVE

To assess the long-term outcomes and efficacy of respiratory retraining therapy in patients with exercise-induced laryngeal obstruction (EILO).

METHODS

A retrospective chart review and prospective questionnaire-based survey were conducted on 88 patients who received respiratory retraining therapy for EILO at our institution over the past 5 years RESULTS: Thirty-four patients were included in the final analysis, with a mean age at symptom onset and age at initial evaluation of 13.67 ± 2.96 and 15.12 ± 3.48, respectively. We found a statistically significant difference in the pretreatment and post-treatment Dyspnea indices following respiratory retraining therapy, with a mean difference of 12.03 ± 7.18 (P < 0.001). When asked about the effectiveness of respiratory retraining therapy, the majority of patients (n = 28) reported improvement (13.3% "a little," 13.3% "somewhat better," 53.3% ("a lot better," and 13.3% complete resolution of symptoms. Only two patients (6.7%) responded that their breathing "did not get better." The most effective therapy techniques cited by patients were abdominal breathing (n = 10), ratio breathing (n = 5), and pursed lips or "straw" breathing (n = 5).

CONCLUSIONS

Respiratory retraining therapy represents an effective technique in both the short-term and long-term management of EILO. This therapy remains the first line in the management of EILO due to its ease of administration, non-invasive nature, and durable effect on breathing function.

Nutritional Status, Dietary Intake, Quality of Life, and Dysphagia in Women With Fibromyalgia

BACKGROUND

Fibromyalgia syndrome (FMS) is an idiopathic chronic disease characterized by widespread musculoskeletal pain, hyperalgesia, and allodynia that has been recently associated with risk of dysphagia.

OBJECTIVE

We aimed to analyze the association between nutritional status, micro- and macronutrient intake, and quality of life (QoL) in a cohort of women with FMS and risk of dysphagia compared to women with FMS without risk of dysphagia.

METHODS

A cross-sectional study was conducted in 46 women with FMS. Risk of dysphagia was assessed by the Eating Assessment Tool (EAT-10) and the Volume-Viscosity Swallow Test (V-VST). The Food Frequency Questionnaire and the Swallowing Quality of Life Questionnaire were used to assess dietary intake and QoL, respectively.

RESULTS

Thirty women with FMS were at risk for dysphagia (65.21%), assessed by the EAT-10. Based on the V-VST, the frequency of risk of dysphagia was 63.04%. Significant differences in body mass index (BMI) were found between women at risk for dysphagia and those without risk. Women at risk for dysphagia had significantly lower overall QoL scores than those women without risk. No significant differences were found for dietary intake and dysphagia risk.

DISCUSSION

Women with FMS at risk for dysphagia have significantly lower BMI values and worse QoL than women without dysphagia risk, supporting the importance of assessing dysphagia in clinical practice in persons with FMS.

Exploring Factors Impacting Engagement in Speech Pathology Intervention for Inducible Laryngeal Obstruction

AIM

Speech pathology is the first-line treatment for inducible laryngeal obstruction (ILO) and involves behavioral techniques to address symptoms and modify maladaptive laryngeal postures. Benefit from speech pathology is reliant on patients engaging in treatment sessions, regular home practice, and generalizing techniques to everyday activities. There is limited research exploring engagement in speech pathology treatment for ILO, particularly from the patient perspective. This study aimed to explore the experiences of living with ILO and how this experience may impact the way patients engage in speech pathology treatment.

STUDY DESIGN

Qualitative study.

METHODS

Semistructured interviews were completed with seven participants exploring their experiences living with ILO, their diagnostic process and their experiences with speech pathology treatment. Data were analyzed using reflexive thematic analysis to determine shared meanings across participants and themes were developed.

FINDINGS

Three major themes were identified - Life with ILO, Challenges of Speech Pathology Treatment, and What Matters to Me. Patients' reports of living with ILO and interacting with speech pathology suggested that these experiences impacted their readiness to start treatment and persist through the challenges of the treatment. Engagement appeared to be positively associated with significant ILO symptom burden and life impact, confidence in the diagnostic process, recommendation for speech pathology treatment, a tailored intervention by a patient-perceived expert in the field and working in a partnership with the speech pathologist to develop a sense of agency. Patients indicated their engagement was negatively influenced by competing time demands, social embarrassment when using symptom relief techniques and laryngeal exercises, and a low ILO symptom burden and life impact.

CONCLUSION

The reasons behind engagement in speech pathology treatment for ILO appear to be a complex interaction between previous experiences of living with ILO including the diagnostic process and the experience of speech pathology treatment. A patient-centered approach to therapy may help to maximize engagement by exploring readiness and expectations for treatment. The greater understanding of the patient experience provided through this study may allow speech pathologists to devise meaningful ways to maximize engagement in treatment for people with ILO.

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.

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.

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.

Multidisciplinary management of inducible laryngeal obstruction and breathing pattern disorder

We provide an overview of the assessment and management of inducible laryngeal obstruction and breathing pattern disorder. We highlight the multidisciplinary team members involved and their essential roles within a complex breathlessness service. We discuss treatments initiated by physiotherapy and speech and language therapy, the importance of joint working, and discuss the high incidence of comorbidities and the association with other respiratory disorders.

Educational aims

Inducible laryngeal obstruction and breathing pattern disorder are common causes of breathlessness.Inducible laryngeal obstruction is an inappropriate, transient, reversible narrowing of the laryngeal area that causes breathlessness and laryngeal symptoms.Breathing pattern disorder is an alteration in the normal biomechanical patterns of breathing that results in intermittent or chronic symptoms, which may be respiratory and/or non-respiratory.People with inducible laryngeal obstruction or breathing pattern disorder often have other comorbidities that will also need addressing.Multidisciplinary assessment and treatment is essential for comprehensive workup and holistic care.Timely assessment and diagnosis can prevent unnecessary medication use and hospital admissions and facilitate effective management of the condition using reassurance, advice, education, breathing retraining and vocal exercises.

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.

Characterization of Ethyl Butyrate-Induced Cough Before and After Breath Control Techniques in Healthy Adults

PURPOSE

Methods for cough elicitation frequently involve aerosolized tussive agents. Here, we sought to determine whether healthy individuals demonstrate a quantifiable cough response after inhaling a volatile ester and if breath control techniques modify this chemically induced cough response.

METHOD

Sixty adult male and female participants inhaled prepared liquid dilutions of ethyl butyrate dissolved in paraffin oil at 20%, 40%, and 60% v/v concentrations in triplicate, with presentation order randomized. We delivered stimuli through a face mask connected to an olfactometer and respiratory pneumotachograph. Participants rated sensations of their urge to cough and pleasantness of the odor while cough airflow was measured. Following baseline testing, participants were randomized to implement pursed-lip breathing or slow-paced breathing after inhaling ethyl butyrate to determine the effects of breath control on cough measures.

RESULTS

Inhaled ethyl butyrate elicited cough in 70% of participants. Higher concentrations of ethyl butyrate resulted in significantly greater sensation of the urge to cough, F(2, 80) = 10.72, p < .001, and significantly more generated coughs, F(2, 63) = 13.14, p < .001. Compared to baseline, participants rated significantly decreased urge to cough during breath control techniques, F(1, 40) = 11.01, p = .0019. No significant changes were observed in the number of generated coughs between baseline and breath control techniques, F(1, 31) = 7.23, p = .01.

CONCLUSIONS

Airborne ethyl butyrate is a tussigenic agent in humans. Our findings provide opportunities for future research directions in normal and disordered cough responses to volatile compounds.

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.

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.

Systematic review of the effectiveness of non-pharmacological interventions used to treat adults with inducible laryngeal obstruction

Introduction

Inducible laryngeal obstruction (ILO) describes transient laryngeal closure during respiration and can cause significant morbidity. Non-pharmacological behavioural therapy is the commonly cited treatment but efficacy is largely unknown.

Aim

To synthesise the current evidence base on the effectiveness of non-pharmacological interventions used to treat adults with ILO.

Methods

Electronic databases (Medline/Embase/CINAHL/PsycINFO/AMED/CENTRAL) were systematically searched, informed by a population, intervention, comparison, outcome framework. Two reviewers independently screened a representative sample, with lead-author completion due to excellent inter-rater reliability. Data was extracted using a predefined piloted form. Methodological quality was appraised (blindly by two reviewers) using the Joanna Briggs Institute Critical Appraisal Tools. A narrative synthesis was performed due to heterogeneity of studies (PROSPERO registration number: CRD42020213187).

Results

Initial searching identified 3359 records. Full-text screening occurred in 92 records and 14 studies, comprising 527 participants, were deemed eligible. All studies were low-level evidence (observational by design, with four case reports), with a high risk of bias; none contained control arms for comparison. Intervention description was inconsistently and poorly described but direction of effect was positive in 76% of outcomes measured. The majority of studies showed a reduction in symptom scores and improved direct laryngeal imaging post intervention; there was an overall reduction, 59.5%, in healthcare utilisation.

Discussion

The literature is in an embryonic state and lacks robust data to truly inform on the effectiveness of non-pharmacological interventions used to treat adults with ILO. However, positive signals in the synthesis performed support non-pharmacological treatment approaches and further development is warranted.

Laryngopharyngeal Reflux: Evolution and Predictive Value of Symptoms and pH-Impedance Features on Clinical Evolution

OBJECTIVES

To investigate the features of patients with laryngopharyngeal reflux (LPR) who did not respond to medical treatment.

STUDY DESIGN

Prospective uncontrolled study.

SETTING

Multicenter study.

METHODS

Patients with LPR at 24-hour HEMII-pH monitoring (hypopharyngeal-esophageal multichannel intraluminal impedance-pH) were prospectively recruited from 3 European university centers. Patients were treated with 3- to 6-month medication (proton pump inhibitor and alginate) and categorized as mild to moderate responders, high responders, or nonresponders according to Reflux Symptom Score (RSS) changes at 6 months posttreatment. The predictive value of the following outcomes was studied: epidemiologic data, HEMII-pH, gastrointestinal endoscopy findings, baseline RSS and Reflux Sign Assessment, and early therapeutic response (6-week RSS).

RESULTS

A total of 148 patients completed the evaluations, accounting for 40 mild to moderate responders (20%-60% RSS changes), 76 high responders (>60% RSS changes), and 32 nonresponders. Nonresponders presented more often with hiatal hernia and lower esophageal sphincter insufficiency when compared with mild to moderate and high responders (P = .032). Baseline otolaryngologic, digestive, and respiratory RSS and the number of pharyngeal reflux events at the HEMII-pH were predictive of the 6-month therapeutic response (P < .05). The early therapeutic response (6 weeks posttreatment) was predictive of the 6-month treatment response.

CONCLUSION

Hiatal hernia and baseline and 6-week RSS were the most predictive indicators of therapeutic effectiveness in patients with LPR.

Visual biofeedback for paradoxical vocal fold motion (PVFM)

Objectives

Paradoxical vocal fold motion (PVFM) is a common condition where the vocal folds inappropriately adduct during inspiration. This results in dyspnea and occasionally significant distress. The condition is thought to be primarily functional, with behavioural therapy considered mainstay in the non-acute setting. However, practice variations and limited access to speech language pathology (SLP) services can pose management challenges. We aimed to examine the efficacy of surgeon performed visual biofeedback as first-line treatment for PVFM.

Study design

Prospective, non-randomized, non-comparative clinical study.

Methods

Adult patients referred for possible PVFM and congruent laryngoscopy findings over a two-year period were included. Patients were excluded if they presented in acute distress, had alternate diagnosis to explain symptomology and/or coexisting untreated lower respiratory pathology. Patients underwent immediate surgeon-performed visual biofeedback on the same visit day. The primary outcome of interest was change in Dyspnea Index (DI) scores pre- and post-intervention 3 months follow-up. The secondary outcome measured was change in asthma medication use from baseline to follow-up.

Results

Of 34 patients presenting, 25 met inclusion criteria. Of these, 72% were female with an average age of 36.9 ± 14.1. Approximately 48% of patients had a diagnosis of well-controlled asthma at presentation and co-morbid psychiatric diagnoses were common (52%). Pre- and post-intervention analysis showed significant improvement in DI scores (p < 0.001) and reduction in bronchodilator use (p = 0.003).

Conclusion

This is a prospective study that evaluates the role of visual biofeedback in PVFM patients. Our data suggests that visual biofeedback effectively reduces short-term subjective symptoms and asthma medication use.

Level of evidence

3

Graphical abstract

UK consensus statement on the diagnosis of inducible laryngeal obstruction in light of the COVID-19 pandemic

Prior to the COVID‐19 pandemic, laryngoscopy was the mandatory gold standard for the accurate assessment and diagnosis of inducible laryngeal obstruction. However, upper airway endoscopy is considered an aerosol‐generating procedure in professional guidelines, meaning routine procedures are highly challenging and the availability of laryngoscopy is reduced. In response, we have convened a multidisciplinary panel with broad experience in managing this disease and agreed a recommended strategy for presumptive diagnosis in patients who cannot have laryngoscopy performed due to pandemic restrictions. To maintain clinical standards whilst ensuring patient safety, we discuss the importance of triage, information gathering, symptom assessment and early review of response to treatment. The consensus recommendations will also be potentially relevant to other future situations where access to laryngoscopy is restricted, although we emphasize that this investigation remains the gold standard.

Outcomes of Paradoxical Vocal Cord Motion Diagnosed in Childhood

OBJECTIVES

To explore long-term patient reported outcome (PRO) measures of pediatric paradoxical vocal cord motion (PVCM) including ease of diagnosis, management, symptom duration and effect on quality of life.

METHODS

All children >8 years of age diagnosed with PVCM at a tertiary pediatric hospital between 2006 and 2017 were invited to complete a survey addressing study objectives.

RESULTS

21/47 eligible participants could be contacted and 18/21 (86%) participated. 78% were female with a mean age at diagnosis of 11.6 and 15.0 years at survey completion. Common PVCM symptoms reported were dyspnea (89%), globus sensation (56%), and stridor (50%). The median time to diagnosis was 3 months (IQR 2-5 months). Nearly all reported being misdiagnosed with another condition, usually asthma, until being correctly diagnosed usually by an otolaryngologist. Participants reported undergoing 3.7 diagnostic studies (range 0-8); pulmonary function testing was most common. Of numerous treatments acknowledged, breathing exercises were common (89%) but only reported helpful by 56%. Use of biofeedback was recalled in 1/3 of subjects but reported helpful in only 14% of them. Anti-reflux, allergy, anticholinergics, inhalers and steroids were each used in >50%, but rarely reported effective. PVCM was reportedly a significant stressor when initially diagnosed but despite 2/3 of participants still reporting ongoing PVCM symptoms, the perceived stress significantly decreased over time (Z = 3.26, P = 0.001).

CONCLUSIONS

This first PVCM PRO study endorses that diagnosis is often delayed and prescribed treatments often viewed as ineffective. While biofeedback and breathing exercises may be critical for short-term control of PVCM episodes, lifestyle changes and stress reduction are likely necessary for long-term management. Increased awareness and improvements in management are needed for this condition.

A Trigger Reduction Approach to Treatment of Paradoxical Vocal Fold Motion Disorder in the Pediatric Population

OBJECTIVES

Paradoxical vocal fold motion disorder (PVFMD), or induced laryngeal obstruction (ILO), is a clinical phenomenon characterized by inappropriate adduction of the true vocal folds during inspiration. The resultant episodes of acute respiratory distress marked by exercise-induced cough, inspiratory stridor, throat tightness, and shortness of breath are often misattributed to asthma despite normal pulmonary function testing results. Although the pathogenesis of the disease remains unclear, the etiology is likely multifactorial with an inflammatory, neurological, and psychiatric basis. Our trigger reduction approach, consisting of a plant-based, Mediterranean-style diet to treat laryngopharyngeal reflux and sinus toilet, aims to dampen the peripheral neuronal hyperexcitability of the laryngopharyngeal tissues that is hypothesized to contribute to this disorder. The primary objective of the present study was to assess for therapeutic efficacy by analyzing pre- and post-treatment subjective scores using four validated indices: Voice Handicap Index (VHI), Reflux Symptom Index (RSI), Dyspnea Index (DI), and Cough Severity Index (CSI).

METHODS

A retrospective chart review of all patients age ≤18 years seen by the senior author between 2012 and 2018 who reported laryngeal spasm (J35.5) as a presenting complaint with no underlying organic diagnosis that otherwise explained the symptom identified the study cohort. Patients were excluded if another cause of their laryngeal spasm was identified or their medical records were incomplete.

RESULTS

Of 80 patients, 24 met the criteria. The most frequent presenting symptom was exercise-induced dyspnea (79%). Of the four measured indices, only a change in DI (P = 0.024) met statistical significance. Of 24 patients, 18 (75%) demonstrated a reduction in DI following our treatment protocol. Using reduction in DI as a continuous variable to assess response, the patient cohort experienced a 4.62 (95% confidence interval [CI]: 0.65-8.6) mean point reduction. Using the eight-point reduction (improvement) in DI as an accepted clinical response to treatment, 8 of 24 patients (33%) experienced a clinically relevant response. Changes in CSI (P = 0.059), RSI (P = 0.27), and VHI (P = 0.25) did not meet statistical significance. Of 24 patients, 8 (33%), 11 (46%), and 7 (29%) demonstrated a reduction in CSI, RSI, and VHI following our trigger reduction protocol, respectively. The patient cohort experienced a mean point reduction of 1.8 (95% CI: -0.1 to 3.7), 1.3 (95% CI: -1.1 to 3.7), and 1.3 (95% CI: -1.0 to 3.6) in CSI, RSI, and VHI, respectively.

CONCLUSIONS

Paradoxical vocal fold motion disorder is a multifactorial disease that poses diagnostic and therapeutic challenges. Early diagnosis and treatment are critical to ensure patient safety, satisfaction, and reduction in health care costs, as mistreatment with asthma pharmacotherapy, intubation, or tracheostomy may exacerbate their dyspnea and lead to preventable hospitalizations. Our results demonstrate that a trigger reduction approach consisting of a plant-based, Mediterranean-style diet and sinus toilet alone may not achieve a clinically meaningful response in the majority of patients. However, given their favorable safety profile, our therapeutic regimen, along with respiratory retraining therapy, may provide symptom relief for selected patients who would otherwise continue to suffer.

Vocal Cord Dysfunction: The Spectrum Across the Ages

Vocal cord dysfunction (VCD) is an upper airway disorder characterized by exaggerated and transient glottic constriction causing respiratory and laryngeal symptoms. Although the origin of VCD symptoms is in the upper airway, it is frequently misdiagnosed as asthma resulting in significant morbidity. VCD can coexist with asthma or mimic allergic conditions affecting the upper airway. VCD may be difficult to diagnose, because patients are intermittently symptomatic and VCD awareness in the medical community is underappreciated. Once VCD is diagnosed and treated, most patients report significant improvement in their symptoms as well as a decrease in asthma medication use.

Short-Term Intensive Therapy and Outcomes for Athletes With Paradoxical Vocal Fold Motion Disorder

Purpose The aim of the study was to develop a treatment for athletes with paradoxical vocal fold motion disorder (PVFMD) based on exercise physiology and learning theory principles and administer it over a preestablished time frame. Method A prospective, repeated-measures, within-subject group design was used. Eleven adolescent/teen athletes diagnosed with PVFMD via laryngoscopy received short-term intensive (STI) therapy. Eight of the athletes returned for extended follow-up. Changes in postexercise inspiratory ( R _i) and expiratory ( R _e) resistances and Modified Borg Dyspnea Scale (MBDS) ratings collected at baseline were compared immediately posttreatment and at extended follow-up. Dyspnea Index scores were collected at baseline and at extended follow-up. Two no-treatment control athletes with PVFMD participated in two exercise challenges-baseline and 6 weeks later. Results Immediately after STI therapy, athletes attained significant improvement in R _i, R _e, and MBDS ratings. These changes were maintained at extended follow-up as well as a significant change in Dyspnea Index scores. The 2 control athletes who were reassessed 6 weeks after baseline experienced negative changes in postexercise R _i and MBDS ratings. Conclusion STI therapy that incorporated individuality, specificity, and variable practice effectively changed outcome measures posttreatment with further improvement observed at extended follow-up. These results provide preliminary evidence for STI therapy for PVFMD.

Spirometry and provocation tests for vocal fold dysfunction diagnosis: a retrospective case series

AIMS Vocal cord dysfunction (VCD) is characterised by paradoxical inspiratory laryngeal motion and is often misdiagnosed as asthma. Definitive diagnosis of VCD is difficult, because laryngoscopy is positive only during symptomatic episodes or upon provocation with exercise or inhaled irritants. The aims of the study were to better characterise the symptomatology of patients with VCD and to evaluate the potential usefulness of less-invasive diagnostic tools, namely provocation tests and spirometry. METHODS Retrospective case series of 84 patients with a typical clinical history of VCD, in whom at least one of the three following diagnostic tests were performed: laryngoscopy, provocation testing, or spirometry. RESULTS The mean age of the patients was 51 years and 74% were women. The principal comorbidities were rhinosinusitis (60%), gastro-oesophageal reflux disease (56%) and atopy (54%). Diagnosis of VCD was confirmed in 73/84 cases (87%), by laryngoscopy (8%), spirometry (84%) and/or provocation tests (68%). CONCLUSIONS VCD remains an underdiagnosed condition. A negative finding on laryngoscopy can lead to false negative diagnosis if it is done when the patient is asymptomatic. Here we show that a clinical suspicion of VCD, evoked by medical history, can be confirmed in many cases by less invasive diagnostic tools such as spirometry and provocation tests. Future well-conducted prospective case-control studies are needed to draw firmer conclusions and to improve the diagnostic accuracy of this condition.

Vocal fold botulinum toxin injection for refractory paradoxical vocal fold motion disorder

OBJECTIVE

Demonstrate efficacy of vocal fold botulinum toxin injection for treatment of refractory paradoxical vocal fold motion disorder (PVFMD).

METHODS

A retrospective review was completed of patients diagnosed with PVFMD who underwent vocal fold botulinum toxin injection for dyspnea symptoms that persisted despite laryngeal control therapy, medical management, and biofeedback therapy. Outcomes measured included overall improvement and resolution of dyspnea symptoms, number of botulinum toxin injections and dose range, change in dyspnea severity index (DSI) scores, and adverse effects of injection therapy.

RESULTS

Thirteen patients (9 female/4 male) underwent vocal fold botulinum toxin injection for refractory PVFMD. The average dose was 2.55 units per vocal fold (range 1.75-5.5 units). The average number of injections was 3.85 (range 1-12 injections). Eleven of 13 (84.6%) patients experienced improvement in dyspnea symptoms, with two of 11 (18.2%) having complete resolution of symptoms. There was a statistically significant improvement in DSI scores because the mean preinjection DSI was 30.43 and improved to 17.43 postinjection (P = 0.017). Temporary breathy voice quality was experienced by all patients with no other adverse side effects.

CONCLUSION

Vocal fold botulinum toxin injection is a safe and effective treatment option for PVFMD and should be considered in patients with refractory dyspnea symptoms following appropriate medical therapy and respiratory retraining protocols.

LEVEL OF EVIDENCE

4 Laryngoscope, 129:808-811, 2019.

Laryngeal Dysfunction: Assessment and Management for the Clinician

The larynx is one of the most highly innervated organs in humans and serves a number of vitally important, complex, and highly evolved biological functions. On a day-to-day basis, the larynx functions autonomously, addressing several roles including airway protection, swallowing, and phonation. In some situations the larynx appears to adopt a functional state that could be considered maladaptive or "dysfunctional." This laryngeal dysfunction can underpin and account for a number of respiratory symptoms that otherwise appear incongruous with a clinical disease state and/or contribute to the development of symptoms that appear "refractory" to treatment. These include conditions associated with a heightened tendency for inappropriate laryngeal closure (e.g., inducible laryngeal obstruction), voice disturbance, and chronic cough. Recognition of laryngeal dysfunction is important to deliver targeted treatment and failure to recognize the condition can lead to repeated use of inappropriate treatment. Diagnosis is not straightforward, however, and many patients appear to present with symptoms attributable to laryngeal dysfunction, but in whom the diagnosis has been overlooked in clinical work-up for some time. This review provides an overview of the current state of knowledge in the field of laryngeal dysfunction, with a focus on pragmatic clinical assessment and management.