Vocal Cord Dysfunction: Masquerader of Asthma

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.

Paradoxical vocal fold motion masquerading as post-anesthetic respiratory distress: A case report

BACKGROUND

Functional vocal cord disorders can be a differential diagnosis for postoperative upper airway obstruction requiring urgent intervention. However, this may be unfamiliar to anesthesiologists who would favor inappropriate airway intervention and increased morbidity.

CASE SUMMARY

A 61-year-old woman underwent cervical laminectomy, followed by laparoscopic cholecystectomy 10 mo later. Despite adequate reversal of neuromuscular blockade, the patient experienced repetitive respiratory difficulty with inspiratory stridor after extubation. After the second operation, the patient was diagnosed with paradoxical vocal fold motion (PVFM) by an otolaryngologist based on the clinical features and fiberoptic bronchoscopy results, and the patient was successfully treated.

CONCLUSION

PVFM should be considered a differential diagnosis if a patient presents with stridor after general anesthesia.

Laryngeal Sensory Symptoms in Spasmodic Dysphonia

OBJECTIVE

The purpose of this research was to determine whether an association between laryngeal hypersensitivity (LH) and spasmodic dysphonia (SD) exists using the LH Questionnaire (LHQ). This study also explored the prevalence of self-reported upper respiratory infection (URI) at the time of SD onset across SD phenotypes.

METHODS

Individuals with and without SD were recruited to complete an online survey measure. All respondents provided demographic information and completed the LHQ. Participants with SD were also asked to provide information about their diagnosed SD subtype and pattern of onset, including whether onset was associated with a URI. The percentage of respondents with and without SD who were classified with LH was determined based on the LHQ. Scores on the LHQ were also compared between the non-SD and the SD groups, as well as between SD phenotypes (adductor SD, abductor SD, and mixed)).

RESULTS AND CONCLUSIONS

Significant associations were found between ADSD and LH, mixed SD and LH, and URI at time of SD onset and increased severity of LH symptoms. These findings suggest that laryngeal sensory symptoms may potentially contribute to or result from motor spasms in SD and/or have implications for its pathophysiology.

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.

Die induzierbare laryngeale Obstruktion (ILO) – Ursachen, klinische Präsentation, Diagnostik und Therapie

Wiederholt episodenhaft auftretende Atemnot ist im Kindes- und Jugendalter ein häufiges Symptom. Neben anstrengungsinduzierter Bronchialobstruktion im Rahmen eines Asthma bronchiale ist eine funktionelle Genese eine sehr häufige Differenzialdiagnose. Dennoch wird diese Diagnose häufig nicht oder mit langer Latenz gestellt. Unter dem Oberbegriff „ILO“ („inducible laryngeal obstruction“) werden sowohl funktionelle supraglottische Obstruktionen durch Kollaps der Knorpelstrukturen als auch Dysfunktionen auf Glottisebene wie „vocal cord dysfunction“ (VCD) subsumiert. Körperliche Anstrengung ist ein häufiger Auslöser; es werden jedoch auch Beschwerdebilder ohne Anstrengungsbezug beobachtet. Es wird der Erkenntnisstand zur Pathophysiologie referiert und die klinische Präsentation beschrieben. Ein wesentlicher Fokus des Artikels liegt im Folgenden auf der Darstellung eines sinnvollen und Ressourcen-orientierten diagnostischen Vorgehens. Der CLE-Test („continuous laryngoscopy exercise test“) als Provokationsmethode unter Wach-Videolaryngoskopie ist der Goldstandard, jedoch wird diese Diagnostik im deutschsprachigen Raum nicht flächendeckend vorgehalten. Dieses Positionspapier stellt daher die diagnostische Wertigkeit verschiedener anderer Diagnostik-Algorithmen und anamnestischer Informationen heraus. Ein weiterer Schwerpunkt des Papiers besteht in der detaillierten Vorstellung geeigneter atemphysiotherapeutischer Interventionen.

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

Can Ultrasound Identify Paradoxical Vocal Fold Movement? A Pilot Study

OBJECTIVE

Vocal cord dysfunction (VCD) is characterized by paradoxical vocal fold movement (PVFM) during inspiration. The aim of this study was to determine whether ultrasound could accurately differentiate between normal and PVFM during respirations in a resting state.

DESIGN

Prospective, single-subject design.

SETTING

Academic medical center.

PATIENTS

A speech-language pathologist who was able to volitionally alternate between normal and PVFM when breathing at rest was recruited to participate in the study.

INTERVENTIONS

The subject was instructed to randomly alternate between normal and PVFM 20 times (10 times each). A single investigator imaged the vocal folds using ultrasound and reported when the subject alternated between the 2 respiratory states.

MAIN OUTCOME MEASURES

The subject recorded when they changed between the 2 respiratory states, whether the investigator identified with the change occurred, and if the correct respiratory state was identified.

RESULTS

The investigator recognized when the subject changed respiratory states and correctly identified the new respiratory state 100% of the time.

CONCLUSIONS

The findings of the current study were promising and suggest that ultrasound may have utility in the diagnosis of VCD. However, because of the preliminary nature of these results, further research is required before recommending its clinical implementation.

Assessing laryngeal function and hypersensitivity

The larynx is one of the most highly innervated organs in humans, adapted to simultaneously deliver several key respiratory functions including airway protection, swallowing and phonation. In some individuals the larynx can adopt a state that could be considered 'dysfunctional' or maladaptive; resulting in or contributing to a range of clinical disorders such as chronic refractory cough, inducible laryngeal obstruction (previously termed paradoxical vocal fold movement or vocal cord dysfunction), muscle tension dysphonia and globus pharyngeus. These disorders appear to display significant overlap in clinical symptomology and in many cases have features of concomitant or allied sensory dysfunction; often described as laryngeal hypersensitivity. The recognition and accurate assessment of both laryngeal dysfunction±hypersensitivity is important to ensure accurate diagnosis and effective delivery of targeted treatment and therapeutic monitoring. Accordingly, there is increasing in the methodologies proposed to assess laryngeal function. These range from simple questionnaires to targeted investigation(s), assessing both sensory function and the laryngeal motor response, under both resting and provoked situations. This review provides a brief overview of the current state of knowledge in the field of laryngeal dysfunction and hypersensitivity assessment.

Common Pediatric Airway Disorders

Pediatric airway disorders may be congenital (anatomical) or acquired (infectious) and may involve the upper, lower, or entire airway, with obstruction being a common feature. The pathophysiology of upper airway obstruction in infants, children, and adolescents is distinctly different due to the anatomic differences that evolve with growth. Accordingly, clinical presentation and consequences of airway obstruction vary by age. This article reviews the common upper airway disorders by age with a review of classic presentation, recommended diagnostic steps, and management considerations for the general pediatrician. [Pediatr Ann. 2019;48(4):e162-e168.].

Multidisciplinary team clinic for vocal cord dysfunction directs therapy and significantly reduces healthcare utilization

BACKGROUND AND OBJECTIVE

Multidisciplinary team (MDT) clinics use an integrated approach to individualize care of complex medical conditions. Vocal cord dysfunction (VCD) is a challenging condition that is likely to benefit from MDT clinics but this has not been researched.

METHODS

A prospective observational cohort study of a novel VCD MDT clinic was conducted in patients with suspected VCD. Relevant questionnaires, medical history, physical examination, spirometry, dynamic computerized tomography (CT) larynx and laryngoscopy were utilized and patients were allocated to treatment pathways depending on putative diagnosis. Speech pathology intervention with laryngeal retraining (LR) was offered and if LR therapy failed botulinum toxin injection was offered. Primary outcome was reductions in healthcare utilization.

RESULTS

Overall, 80 consecutive patients were included in analyses. A definitive diagnosis of VCD was made in 56 of 80 (70%) patients. After LR (n = 35), emergency department (ED)/hospital admissions declined significantly in the subsequent 12 months (P = 0.001). General practice visits also reduced (P < 0.001). Botulinum toxin injections were administered in 21 patients unresponsive to LR therapy and both general practice and ED/hospital visits declined (P < 0.001 and P = 0.01, respectively) after injection.

CONCLUSION

A multidisciplinary approach to VCD confers benefit and can be used to allocate appropriate management leading to a reduction in healthcare utilization.

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.

Does treatment of paradoxical vocal fold movement disorder decrease asthma medication use?

OBJECTIVES/HYPOTHESIS

To determine whether diagnosis and treatment of paradoxical vocal fold movement disorder (PVFMD) leads to decreased asthma medication use. Secondary objectives include determining initial rate of asthma medication use, characterizing symptom improvement, and correlating with pulmonary function testing (PFT).

STUDY DESIGN

Prospective observational study.

METHODS

Patients newly diagnosed with PVFMD at a single institution were recruited to participate. Medication questionnaires were completed at the initial visit, at the first return visit for therapy, and at 6 months. PFTs were reviewed when available.

RESULTS

Sixty-six patients were recruited; the study was closed early because findings reached significance. Fifty-six patients (85%) were taking asthma medication at presentation. Forty-four patients presented with PFTs, and two-thirds were normal. Forty-two patients completed follow-up questionnaires; 79% decreased asthma medication use (P < .001), and 82% reported symptom improvement. Seventy-seven percent of patients participated in therapy and 23% did not, with equal rates of decrease in asthma medication use between these groups. Outcomes did not vary based on PFT pattern (i.e., obstructive vs. nonobstructive, P = .75).

CONCLUSIONS

Diagnosis and treatment of PVFMD lead to a decline in asthma medication use. This decrease occurred alongside symptom improvement and irrespective of PFT findings. Use of asthma medication in this patient population is high, at 85%.

LEVEL OF EVIDENCE

4. Laryngoscope, 127:1531-1537, 2017.

Sports Ultrasound: Applications Beyond the Musculoskeletal System

BACKGROUND

Traditionally, ultrasound has been used to evaluate musculoskeletal injuries in athletes; however, ultrasound applications extend well beyond musculoskeletal conditions, many of which are pertinent to athletes.

EVIDENCE ACQUISITION

Articles were identified in PubMed using the search terms ultrasound, echocardiogram, preparticipation physical examination, glycogen, focused assessment with sonography of trauma, optic nerve, and vocal cord dysfunction. No date restrictions were placed on the literature search.

STUDY DESIGN

Clinical review.

LEVEL OF EVIDENCE

Level 4.

RESULTS

Several potential applications of nonmusculoskeletal ultrasound in sports medicine are presented, including extended Focused Assessment with Sonography for Trauma (eFAST), limited echocardiographic screening during preparticipation physical examinations, assessment of muscle glycogen stores, optic nerve sheath diameter measurements in athletes with increased intracranial pressure, and assessment of vocal cord dysfunction in athletes.

CONCLUSION

Ultrasound can potentially be used to assist athletes with monitoring their muscle glycogen stores and the diagnosis of multiple nonmusculoskeletal conditions within sports medicine.

Vocal cord dysfunction: a review

Vocal cord dysfunction (VCD) is a term that refers to inappropriate adduction of the vocal cords during inhalation and sometimes exhalation. It is a functional disorder that serves as an important mimicker of asthma. Vocal cord dysfunction can be difficult to treat as the condition is often underappreciated and misdiagnosed in clinical practice. Recognition of vocal cord dysfunction in patients with asthma-type symptoms is essential since missing this diagnosis can be a barrier to adequately treating patients with uncontrolled respiratory symptoms. Although symptoms often mimic asthma, the two conditions have certain distinct clinical features and demonstrate specific findings on diagnostic studies, which can serve to differentiate the two conditions. Moreover, management of vocal cord dysfunction should be directed at minimizing known triggers and initiating speech therapy, thereby minimizing use of unnecessary asthma medications. This review article describes key clinical features, important physical exam findings and commonly reported triggers in patients with vocal cord dysfunction. Additionally, this article discusses useful diagnostic studies to identify patients with vocal cord dysfunction and current management options for such patients.

Irritant-Induced Paradoxical Vocal Fold Motion Disorder

Objectives

To review our experience with the diagnosis and treatment of irritant-induced paradoxical vocal fold motion disorder (IPVFMD).

Study Design

Retrospective chart review.

Setting

Tertiary academic referral center.

Subjects and Methods

Thirty-four cases that met IPVFMD criteria and 76 cases of non-IPVFMD were selected from a database of patients with paradoxical vocal fold motion disorder—the diagnosis of which was made on the basis of flexible fiberoptic laryngoscopy and augmented by an odor challenge. Clinical charts were reviewed to document history of environmental allergies, pulmonary disease, gastroesophageal reflux, psychiatric disorder, fibromyalgia, tobacco use, alcohol use, dysphonia, cough, dysphagia, and treatment outcomes.

Results

There were no statistical differences between the IPVFMD and non-IPVFMD groups. Of the patients who were assigned and attended laryngeal control therapy, 13 (65%) reported improvement of symptoms. Symptom improvement increased to 100% in those patients who attended at least 2 laryngeal control therapy sessions.

Conclusions

IPVFMD should be considered in patients presenting with respiratory symptoms after irritant exposure. Sensitivity of diagnosis can be improved via a standardized approach consisting of a careful history and physical examination, including laryngoscopy in the presence of triggers. Laryngeal control therapy is a well-tolerated and effective method of managing IPVFMD.

Differential diagnosis in paradoxical vocal fold movement (PVFM): an interdisciplinary task

OBJECTIVES

The objective of this study was to contribute to the discussion of differential diagnosis in paradoxical vocal fold movement (PVFM), a disorder frequently associated with episodes of breathing difficulty and stridor. Because of analogous respiratory symptoms, PVFM is often misdiagnosed as asthma. Additional evidence suggests the association of factors such as respiratory struggle during physical exertion, digestive reflux, and respiratory allergies with PVFM, particularly in athletes and young females. Interdisciplinary attention is warranted to avoid unnecessary utilization of medical resources and potential delay in the application of proper treatment.

METHODS

A description of critical points in PVFM differential diagnosis is proposed, featuring the assessment of a seven-year-old female with a history of behaviors considered to exacerbate voice fatigue symptoms. Noticeably, the child has consistently demonstrated tiredness and respiratory difficulties during physical education classes. Past use of oral steroids to reduce respiratory problems was applied with no improvement; short-acting beta 2-agonists have been also tried with mild improvement. Indications of instability and effort associated with respiratory-phonatory functions were demonstrated. Furthermore, there was evidence of GERD and seasonal allergies.

RESULTS

The literature suggests an association of factors such as respiratory struggle during physical exertion, unwanted vocal effort, GERD, and respiratory allergies in individuals with PVFM, particularly in young females. A diagnosis of PVFM was suggested, in association with paradoxical vocal folds motion caused by respiratory difficulties verified by laryngeal examination.

CONCLUSIONS

In PVFM, the vocal folds adduct during inhalation, thereby restricting the airway opening. Inconsistent vocal folds movement during phonation may also lead to PVFM symptoms. Acute bronchospasm/asthma-like symptoms, as well as additional morbidity may impact accuracy of diagnosis, leading to unnecessary use of asthma medications and office/emergency room consultations.

Dyspneic athlete

Breathing concerns in athletes are common and can be due to a wide variety of pathology. The most common etiologies are exercise-induced bronchoconstriction (EIB) and paradoxic vocal fold movement disorder (PVFMD). Although some patients may have both, PVFMD is often misdiagnosed as EIB, which can lead to unnecessary treatment. The history and physical exam are important to rule out life threatening pulmonary and cardiac causes as well as common conditions such as gastroesophageal reflux disease, sinusitis, and allergic etiologies. The history and physical exam have been shown to be not as vital in diagnosing EIB and PVFMD. Improvement in diagnostic testing with office base spirometry, bronchoprovocation testing, eucapnic voluntary hyperpnea (EVH) and video laryngoscopy are essential in properly diagnosing these conditions. Accurate diagnosis leads to proper management, which is essential to avoid unnecessary testing and save healthcare costs. Also important to the physician treating dyspnea in athletes is knowing regulations on medications, drug testing, and proper documentation needed for certain organizations. The differential diagnosis of dyspnea is broad and is not limited to EIB and PVFMD. Ruling out life threatening cardiac and pulmonary causes with a proper history, physical, and appropriate testing is essential. The purpose of this review is to highlight recent literature on the diagnosis and management of EIB and PVFMD as well as discuss other potential causes for dyspnea in the athlete.

Paradoxic vocal fold movement disorder

Paradoxical Vocal Fold Movement Disorder (PVFMD) is a cause of dyspnea that can mimic or occur alongside asthma or other pulmonary disease. Treatment with Laryngeal Control Therapy is very effective once the entity is properly diagnosed and contributing comorbidities are managed appropriately. In understanding the etiology of PVFMD, focus has broadened beyond psychiatric factors alone to include the spectrum of laryngeal irritants (laryngopharyngeal reflux, allergic and sinus disease, sicca, and possibly obstructive sleep apnea). The following is a discussion of the history, terminology, epidemiology, diagnosis, comorbid conditions, and treatment of this entity.

Vocal cord dysfunction

Vocal cord dysfunction (VCD), generally characterized by paradoxical closure of the vocal cords during inspiration, is a common mimicker of asthma and of other conditions that cause upper airway obstruction. As a result, it is frequently overlooked and often misdiagnosed, resulting in administration of excessive medications or other unnecessary interventions, with resultant morbidity. This article explores the clinical features, proposed causes, diagnostic considerations, and management of VCD, as well as some differences between VCD and asthma that can aid in differentiating these two diagnoses in the clinical setting.

Co-existing paradoxical vocal cord motion and asthma in a young child

We are reporting a 7½-year-old child who had coexisting paradoxical vocal cord motion (PVCM) and asthma. There are only a few reported cases of PVCM in children younger than 10 years of age. Thus diagnosis mainly relies on high index of suspicion for these children. Missing PVCM diagnosis can lead to unnecessary diagnostic and therapeutic interventions to control asthma. We hope that this case report would increase the awareness of such coexistence in such a young age group.

The importance of recognizing paradoxical vocal fold dysfunction: A case report of a 13-year-old girl presenting with stridor

The present report details the case of a 13-year-old girl who presented to the emergency department with stridor. Treatment for presumed reactive airway disease was attempted with antibiotics, nebulized adrenaline masks and high-dose corticosteroids. Over the next month, she presented repeatedly in a similar fashion and was admitted to hospital on three separate occasions. Ultimately, she was referred to the Centre for Paediatric Voice and Laryngeal Function at The Hospital for Sick Children (Toronto, Ontario) for a speech-language pathology evaluation and direct laryngoscopy. The patient was diagnosed with paradoxical vocal fold dysfunction. After a brief treatment session with a speech-language pathologist, her stridor completely resolved and paradoxical inspiratory vocal fold adduction was no longer visualized on direct laryngoscopy. The present case highlights the fact that paradoxical vocal fold dysfunction can mimic other entities that present with stridor, and misdiagnosis can result in significant morbidity. Investigation into a patient's social history and stressors can facilitate the diagnosis, and can avoid unnecessary and potentially harmful medical and surgical interventions.

Laryngeal and respiratory patterns in patients with paradoxical vocal fold motion

The purposes of this study were to determine the differences in spirometric measures obtained from patients with endoscopically-documented paradoxical vocal fold motion (PVFM) and to compare them to a group of normal subjects without endoscopically-documented paradoxical vocal fold motion during non-provocative breathing and following speech. Thirty eight subjects with documented paradoxical vocal fold motion using transnasal flexible laryngoscopy (TFL) and no history of asthma and 21 normal subjects with documented normal breathing patterns and normal findings on endoscopy underwent flow-volume loop studies. Endoscopic judgments of vocal fold motion from three breathing conditions were made by two observers. The results of the endoscopic judgments indicate that paradoxical motion occurs whether breathing through the nose or mouth in the PVFM subjects, mainly after speaking and inhalation. In addition, the spirometry results indicated that the inspiratory measure of FIVC%, FVC% and FIV(0.5)/FIVC were significantly lower in the PVFM group compared to the normal subjects. The data supports the hypothesis that in patients with PVFM, inspiratory spirometric values play a role in identifying patients with PVFM. The finding of vocal fold closure following a speech utterance in the majority of the PVFM subjects but not in the normal control group warrants further investigation.

Vocal cord dysfunction: an update

OBJECTIVES

To review the clinical manifestations of vocal cord dysfunction (VCD) and to discuss new developments in the diagnosis and treatment.

DATA SOURCES

PubMed searches were performed for articles published regarding presentation, pathogenesis, diagnosis, and treatment options of VCD using the keywords vocal cord dysfunction, pathogenesis, clinical features, diagnosis, and management.

STUDY SELECTION

Articles were selected based on their relevance to the topic of this review. The newest developments in VCD were defined by articles published in the past 8 years.

RESULTS

The exact cause and pathogenesis remain unclear, although laryngeal hyperresponsiveness likely plays a role in a subset of patients. Certain findings on spirometry are often interpreted to suggest VCD, but recent studies have had varying results on how useful these are in the diagnosis of VCD. Diagnosis is made by direct visualization of the adduction of the vocal cords via rhinolaryngoscopy, but the method used to provoke symptoms and adduction varies. Other noninvasive tests have been evaluated as well.

CONCLUSION

The early recognition and treatment of VCD are imperative to prevent the misdiagnosis and mismanagement of asthma. In addition, VCD and asthma can occur together. The origin and pathogenesis of VCD need to be better defined. More studies comparing the provocation methods during laryngoscopy may be helpful in further standardizing a diagnostic test. Further research is needed to determine whether other noninvasive tests are as effective in diagnosing VCD as laryngoscopy.

Diagnostic criteria for the classification of vocal cord dysfunction

Vocal cord dysfunction (VCD) is a syndrome characterized by paroxysms of glottic obstruction due to true vocal cord adduction resulting in symptoms such as dyspnea and noisy breathing. Since first described as a distinct clinical entity in 1983, VCD has inadvertently become a collective term for a variety of clinical presentations due to glottic disorders. Despite an increased understanding of laryngeal function over the past 25 years, VCD remains a poorly understood and characterized entity. Disparities in the literature regarding etiology, pathophysiology, and management may be due to the historic approach to this patient population. Additionally, disorders clearly not due to paroxysms of true vocal cord adduction, such as laryngomalacia, vocal cord paresis, and CNS causes, need to be differentiated from VCD. Although a psychologic origin for VCD has been established, gastroesophageal reflux disease (GERD), nonspecific airway irritants, and exercise have also been associated with intermittent laryngeal obstruction with dyspnea and noisy breathing. VCD has been repeatedly misdiagnosed as asthma; however, the relationship between asthma and VCD is elusive. There are numerous case reports on VCD, but there is a paucity of prospective studies. Following an in-depth review of the medical literature, this article examines the available retrospective and prospective evidence to present an approach for evaluation of VCD including: (1) evaluation of factors associated with VCD, (2) differential diagnosis of movement disorders of the upper airway, and (3) clinical, spirometric, and endoscopic criteria for the diagnosis.

Paradoxical vocal fold motion dysfunction in asthma patients

BACKGROUND AND OBJECTIVE

Paradoxical vocal fold motion dysfunction (PVFMD) is a disorder of the larynx characterized by adduction of the vocal cords during the respiratory cycle leading to symptoms of extrathoracic airway obstruction. PVFMD mimics asthma and patients with PVFMD (PVFMD+) are often diagnosed incorrectly as refractory asthma and receive unnecessary treatment. This study determined the prevalence of PVFMD in asthma patients and described the relationship between asthma and PVFMD.

METHODS

A descriptive study of 94 asthmatic patients and 40 control subjects, all of whom were examined via laryngoscopy and had pulmonary function tests were performed.

RESULTS

The prevalence of PVFMD was 19% (n = 18) in the asthmatic group and 5% (n = 2) in the control group (P < 0.001). No relationship was found between presence of PVFMD, asthma attacks and asthma severity (P > 0.05). Laryngopharyngeal reflux and allergy were significantly more prevalent in the PVFMD+ group than in the group without PVFMD (PVFMD-) (P < 0.05). The most common symptoms in the PVFMD+ patients were difficulty in breathing (88%), inspiratory stridor (66%) and a choking sensation (50%) and the most common symptoms in PVFMD- asthmatic patients were cough (63%), dyspnoea (55%) and wheezing (51%).

CONCLUSIONS

Asthma seems to facilitate the formation of the paradoxical dysfunction in the larynx as the prevalence of PVFMD in asthma patients is significantly higher than in patients with out asthma.

Vocal cord dysfunction: an important differential diagnosis of bronchial asthma

INTRODUCTION

Intermittent paradoxical closure of the vocal cords can induce major attacks of dyspnea. Such attacks, called "vocal cord dysfunction" (VCD), are an important element in the differential diagnosis of intractable bronchial asthma.

METHODS

Selective review of the literature.

RESULTS

The etiology of VCD is unclear. Its clinical manifestations can mimic those of bronchial asthma. Standard asthma medication fails to improve the dyspnea of VCD, which is subjectively perceived as life-threatening. Consequently, patients with unrecognized VCD may be treated with very high doses of anti-asthmatic medication, including systemic corticosteroids, leading to major iatrogenic morbidity. No prospective studies are available on this subject to date. Experts estimate that 3% to 5% of persons diagnosed as having bronchial asthma actually suffer from VCD. Because of the brevity of the attacks, which usually last only 1-2 minutes, VCD is difficult to diagnose with the methods generally used to diagnose asthma. Evidence-based therapeutic approaches are still lacking, but speech therapy, including special breathing techniques with relaxation of the throat, seems to control the attacks of dyspnea in most patients.

DISCUSSION

An improved knowledge of the clinical manifestations of VCD can help physicians diagnose it correctly. Early diagnosis can prevent prolonged erroneous treatment based on a false diagnosis of bronchial asthma and thereby obviate the iatrogenic side effects of long-term corticosteroid therapy, as well as the resulting economic losses.

Pulse oximetry coupled with spirometry in the emergency department helps differentiate an asthma exacerbation from possible vocal cord dysfunction

PURPOSE

Spirometry performed by adolescents with refractory wheeze or stridor and respiratory distress, with normal room air oxygen saturation, may differentiate subjects not having an acute asthma exacerbation (AE-) from those who are (AE+). A subpopulation may also be identified that has flow volume loop (FVL) patterns consistent with vocal cord dysfunction (VCD).

METHODS

Spirometry was performed by adolescents who presented to a pediatric emergency department (ED) with respiratory distress attributed to an acute AE who, after therapy, were still symptomatic and had room air oxygen saturation > or = 97%. Spirometry findings were classified as: (a) consistent with an acute AE, (b) variable extrathoracic airway obstruction pattern consistent with VCD, (c) a combination of the two, or (d) normal airflow.

RESULTS

Of 2,073 adolescent visits for asthma seen in the ED in 2005, 20 encounters among 17 adolescents were examined during the period of 0700-2200 on weekdays when an investigator was available, of which, 15 encounters were classified as AE-. In the AE- group, nine had FVL evidence of variable extrathoracic airway obstruction consistent with VCD, and six had normal spirometry. Three of the five encounters that were AE+ had FVL evidence consistent with VCD.

CONCLUSIONS

Spirometry, performed on therapy-resistant wheezing or stridorous adolescent patients in respiratory distress with oxygen saturation > or =97%, may help differentiate patients who are not having an acute AE from those who are. In those subjects not having an acute AE, respiratory distress may prove to be due to VCD.

Paradoxical vocal cord motion--a dangerous imitator of airway emergencies

We report a case of stridor in a 32 year old woman. Initial laryngoscopy demonstrated adduction of the vocal cords on inspiration, which reverted to abduction on induction of general anaesthesia. The airway was structurally normal. The most likely diagnosis was paradoxical vocal cord motion, a condition in which psychological stress can precipitate respiratory symptoms and signs due to involuntary adduction of the vocal cords during inspiration. Its importance to the anaesthetist lies in its ability to masquerade as a serious airway or respiratory condition.

Effects of biofeedback in phonatory disorders and phonatory performance: a systematic literature review

The purpose of this article was to systematically review the literature on the effects of biofeedback therapy in the domain of phonatory disorders and phonatory performance, using studies in peer-reviewed journals. An extensive definition of biofeedback is given and its place in voice treatment is defined. Eighteen group or case studies or reports considering the effects of electromyographic, laryngoscopic and acoustic biofeedback in dysphonic patients (hyperfunctional voice disorders, hypofunctional voice disorders, psychogenic voice disorder, laryngeal trauma, total laryngectomy, vocal cord dysfunction) and participants with normal voices are included and an analysis of procedure as well as research design and results is presented. The usefulness of biofeedback in phonatory disorders and performance was to be interpreted based on tendencies, since there is a lack of randomized controlled efficacy studies. In only 3 of 18 studies (16.7%) did biofeedback therapy fail to improve voice quality or not result in better results than other forms of therapy. Recommendations for improved methodologies are made, which include the use of acoustic voice quality parameters.

Eucalyptus as a specific irritant causing vocal cord dysfunction

BACKGROUND

Vocal cord dysfunction (VCD) is a well-recognized clinical entity that frequently mimics asthma and is characterized by inappropriate adduction of the vocal cords during inspiration. The pathogenesis of VCD has not yet been defined. The only previous report suggested that respiratory irritants may trigger paradoxical motion of the vocal cords.

OBJECTIVE

To report the case of a 46-year-old woman with VCD precipitated by eucalyptus exposure.

METHODS

A masked flexible fiberoptic nasolaryngoscopy was performed to confirm whether VCD occurred with eucalyptus and not with other known respiratory irritants. The patient underwent inhalation challenges consisting of water, ammonia, pine oil, and a combination of eucalyptus (dried leaves) and ammonia. Two independent observers before patient challenge could not identify eucalyptus.

RESULTS

Vocal cord dysfunction occurred within minutes of exposure to eucalyptus. This is the first report to prospectively document that a specific irritant, eucalyptus, can precipitate VCD. Negative skin prick test results, total IgE level, and negative IgE eucalyptus-specific antibodies support a nonimmunologic mechanism.

CONCLUSIONS

A new pathogenic mechanism for this clinical entity is supported by our observations. Furthermore, a nonimmunologic mechanism in which respiratory irritants may induce VCD is suspected. Future studies to elucidate this mechanism need to be performed in individuals with irritant-specific VCD.

Inspiratory muscle strength training with behavioral therapy in a case of a rower with presumed exercise-induced paradoxical vocal-fold dysfunction

Paradoxical vocal fold dysfunction (PVFD) with high effort exercise can result in disruptions to ventilation, dyspnea, inspiratory stridor, elevated heart rate, and syncope. This single subject study experimentally tested an inspiratory muscle strength training (IMST) program with behavioral therapy on a 15-year-old male crew member. Outcome variables were maximum inspiratory pressure (MIP), and dyspnea ratings. Following 5 weeks of IMST, MIP increased by 93% from baseline function while dyspnea ratings substantially decreased. Outcome included successful competition with his high-school crew team, a task he was previously unable to complete. Discussion focuses on IMST combined with traditional approaches of voice therapy for treating PVFD.

Vocal cord dysfunction in children and adolescents

Vocal cord dysfunction (VCD) is a nonorganic disorder of the larynx that involves unintentional paradoxical adduction of the vocal cords while breathing. The resultant symptoms can include dyspnea, chest tightness, cough, throat tightness, wheezing, or voice change. Most patients with VCD are female, and among adolescents and children, VCD tends to be triggered by exercise and is typically confused with exercise-induced asthma. Both gastroesophageal reflux disease (GERD) and psychiatric illness have been reported as having strong associations with VCD, although, to date, there is no evidence that either causes VCD. VCD often coexists with asthma, and should be suspected in any patient in whom asthma treatment fails. Confirming the diagnosis involves direct visualization of abnormal vocal cord motion, and this usually only occurs during symptoms. Adolescent athletes often require free running exercise challenge to reproduce their symptoms and confirm abnormal vocal cord motion laryngoscopically. The primary treatment for VCD involves a combination of patient education and speech therapy, and, in most cases, patients may resume their activities without significant limitation.

Psychophysiologic treatment of vocal cord dysfunction

BACKGROUND

Vocal cord dysfunction (VCD) is an obstructive upper airway syndrome that frequently mimics asthma and for which there is no empirical treatment of choice.

OBJECTIVE

To describe two military service members experiencing VCD who were treated with psychophysiologic self-regulation training.

METHODS

Both cases were active-duty military members with VCD confirmed by laryngoscopy They each received biofeedback self-regulation training to decrease tension in the extrinsic laryngeal musculature.

RESULTS

Both patients responded to the treatment, denied the presence of dsypnea, and had resumed military physical training.

CONCLUSIONS

Psychophysiologic self-regulation strategies both with and without concurrent speech therapy positively impacted VCD symptoms.

Inspiratory stridor in elite athletes

STUDY OBJECTIVES

Diagnosis and medical intervention for exercise-induced bronchospasm (EIB) are often based on self-reported symptoms, without spirometric confirmation. Inspiratory stridor (IS), a symptom of vocal cord dysfunction (VCD), is frequently mistaken for EIB wheeze. Athletes with exercise IS that spontaneously resolves on activity cessation are suspect for VCD and may not have EIB. This study estimated IS prevalence in elite athletes and determined its relationship to EIB.

SUBJECTS/METHODS

Three hundred seventy athletes (174 female and 196 male subjects) provided a medical history, and underwent spirometry before and after exercise challenge. Exercise challenges were conducted in cold, dry ambient conditions. EIB positive (EIB +) was defined as a > or = 10% postexercise fall in FEV(1). Athletes were monitored for IS during exercise; 78.4% of the athletes in this study (n = 290) were tested on multiple occasions.

RESULTS

EIB was identified in 30% of 370 athletes tested (58 female and 53 male subjects). IS was observed in 5.1% (18 female and 1 male subjects) during exercise and spontaneously resolved in these subjects within 5 min after exercise cessation. Ten IS-positive (IS +) athletes (52.6%) were EIB +, and 8 of these athletes had a previous EIB diagnosis; however, beta(2)-agonist treatment resolved IS in only 2 subjects. Eight of nine IS +/EIB-negative (EIB -) athletes had a previous EIB diagnosis; seven subjects received beta(2)-agonist treatment with no IS resolution. Resting spirometric measurements did not distinguish IS, but postexercise mid-flow (FEF(50)/FIF(50)) ratio > 1.5 was more frequent (33%, p < 0.05) among IS + athletes. The FEF(50)/FIF(50) ratio was higher for IS +/EIB + athletes than for IS -/EIB + athletes (1.97 +/- 1.69 vs 0.81 +/- 0.39, p < 0.05). The postexercise fall in FVC was greater (p < 0.05) for IS +/EIB - athletes (9.2 +/- 5.0%) than for IS-negative (IS -) /EIB - athletes (5.3 +/- 4.3%). No difference in postexercise FEV(1) was identified between IS + and IS - athletes (within EIB + or EIB - groups).

CONCLUSIONS

Five percent of athletes were IS +, with EIB comorbidity observed in 53% of these subjects. Misdiagnosis of IS as EIB is common. The lack of a beta(2)-agonist response in combination with postexercise serial spirometry can be useful in excluding solitary IS and confirming EIB diagnosis.

Vocal cord dysfunction induced by methacholine challenge testing

STUDY OBJECTIVES

To determine whether methacholine challenge testing (MCT) provokes vocal cord dysfunction (VCD), as evidenced by inspiratory vocal cord closure on direct laryngoscopy, and whether spirometry and flow-volume loops (FVLs) demonstrate any changes that are suggestive of VCD.

DESIGN

Prospective, controlled study.

SETTING

Army medical center.

PATIENTS

Thirty-four subjects all with normal baseline spirometry. Ten subjects had documented evidence of VCD, 12 subjects had exercise-induced asthma (EIA) and reactive MCT, and 12 subjects served as healthy asymptomatic control subjects.

METHODS

Measurement of spirometry with FVLs and direct laryngoscopy of the vocal cords performed immediately before and after subjects had undergone MCT.

RESULTS

Evidence of inspiratory vocal cord adduction was found in four VCD patients. Two patients had adducted vocal cords at baseline, and their conditions were unchanged after undergoing MCT. Two other patients had normal conditions at baseline and demonstrated acute inspiratory vocal cord adduction after undergoing MCT. None of the patients in the EIA or control groups had evidence of VCD at baseline or after undergoing MCT. Truncation of the inspiratory limb of the FVL after MCT was noted in five patients, which correlated with evidence of VCD in 60% of these patients. One EIA patient had truncation of the inspiratory FVL after MCT, and no changes were found in the control group. A comparison of spirometry between EIA patients and VCD patients with and without evidence of inspiratory vocal cord adduction during MCT showed no significant differences.

CONCLUSIONS

The findings suggest that MCT may cause an acute episode of vocal cord adduction and that positive results may not reflect underlying reactive airways disease. However, a flattening or truncation of the inspiratory FVL after the patient undergoes MCT is not diagnostic for the presence of inspiratory vocal cord adduction.

Psychological aspects of asthma

Asthma can be affected by stress, anxiety, sadness, and suggestion, as well as by environmental irritants or allergens, exercise, and infection. It also is associated with an elevated prevalence of anxiety and depressive disorders. Asthma and these psychological states and traits may mutually potentiate each other through direct psychophysiological mediation, nonadherence to medical regimen, exposure to asthma triggers, and inaccuracy of asthma symptom perception. Defensiveness is associated with inaccurate perception of airway resistance and stress-related bronchoconstriction. Asthma education programs that teach about the nature of the disease, medications, and trigger avoidance tend to reduce asthma morbidity. Other promising psychological interventions as adjuncts to medical treatment include training in symptom perception, stress management, hypnosis, yoga, and several biofeedback procedures.

Vocal cord dysfunction mimics asthma and may respond to heliox

Vocal cord dysfunction (VCD), an under appreciated cause of wheezing, may be mistaken for or coexist with asthma. The vocal cords involuntarily adduct during inspiration, leading to inspiratory or biphasic wheezing. Asthma therapy offers no benefit and may result in injury. Proof of diagnosis requires endoscopy during an episode. Definitive therapy involves voice training by a speech pathologist, but heliox (20% to 40% oxygen in helium) has been used to reduce symptoms, resulting in dramatic improvement in wheezing and less anxiety. A retrospective review of recent experience with heliox treatment for patients with VCD was conducted, using a search of computerized inpatient and outpatient physician dictation reporting at Scott & White Memorial Hospital and Clinic. Five patients age 10 to 15 years were treated with a favorable response in four. There were no complications of therapy. A high index of suspicion can lead to the diagnosis of VCD, avoiding expensive, inappropriate, and harmful therapy. A trial of heliox inhalation for patients with symptomatic VCD may prove beneficial, analogous to the "reliever" role of beta agonists for asthma. Home or school use of heliox may reduce acute care visits, while voice training ("controller" therapy) is instituted.

Non-asthmatic respiratory symptomatology

Because of the common nature of asthma and the attention this disease has been given in recent years, it is important to consider the possibility of other disorders that may present in a similar manner to asthma. Failure to consider alternative diagnoses often leads to inappropriate treatment with medications such as systemic corticosteroids that result in untoward morbidity. This review will discuss several diseases originating not only in the tracheobronchial tree but also in extrapulmonary sites, such as the gastrointestinal tract, that may be mistakenly diagnosed as asthma. Newly described entities such as irritant vocal cord dysfunction and exercise-induced hyperventilation syndrome are discussed in this article, as is new information pertaining to well-established diseases such as Churg-Strauss syndrome and sarcoidosis.

Prognosis of occupational asthma

BACKGROUND

Occupational asthma (OA), is an important clinical condition with substantial morbidity and associated costs. Since the original description of OA we have learned a great deal about the natural history. The prognosis of OA is determined by many factors. These factors and confounding variables in the presentation of OA will be presented.

RESULTS

A review of the available literature indicates that OA may have complete resolution or may persist for years following its initial presentation.

CONCLUSION

The importance of timely removal or adequate respiratory protection from potential sources of OA is highlighted.

Vocal cord dysfunction in patients with exertional dyspnea

STUDY OBJECTIVES

To evaluate patients for vocal cord dysfunction (VCD) in a military population presenting with symptoms of exertional dyspnea.

DESIGN

Cross-sectional, controlled study.

SETTING

Pulmonary disease clinic at an army tertiary care center.

PATIENTS

Forty military patients with complaints of exertional dyspnea and 12 military asymptomatic control subjects.

INTERVENTION

Patients underwent direct visualization of vocal cords with flexible laryngoscopy before and after exercise to evaluate for presence of inspiratory vocal cord adduction.

MEASUREMENTS AND RESULTS

Complete evaluation for all patients consisted of spirometry with flow-volume loops, lung volumes, diffusing capacity, and maximum voluntary ventilation at rest; chest radiograph; methacholine bronchoprovocation testing; and a maximal cardiopulmonary exercise test with expiratory gas analysis. Fifteen percent of patients studied prospectively were found to have VCD, whereas all control subjects were negative for VCD. There was minimal difference in pulmonary function testing between VCD-positive and VCD-negative patients, whereas control subjects had higher spirometric values. Twenty percent of VCD-positive patients had abnormal flow-volume loops compared with 14% of patients without VCD, but after methacholine, 60% of VCD-positive patients developed abnormal flow-volume loops. In the VCD-positive group, 60% had a positive methacholine response, but there was less decrease in FEV(1)/FVC ratio compared with either VCD-negative patients or control subjects.

CONCLUSIONS

Paradoxical inspiratory vocal cord closure is a frequent occurrence in patients with symptoms of exertional dyspnea and should be strongly considered in their evaluation.