Related Experiment Video
Updated: Dec 26, 2025

Investigating the Three-dimensional Flow Separation Induced by a Model Vocal Fold Polyp
Published on: February 3, 2014
Paradoxical Vocal Fold Motion in Difficult Asthma Is Associated with Dysfunctional Breathing and Preserved Lung
Joy Lee1, Eve Denton1, Ryan Hoy1
1Allergy, Asthma & Clinical Immunology, The Alfred Hospital, Melbourne, VIC, Australia; School of Public Health & Preventive Medicine, Monash University, Melbourne, VIC, Australia.
Background:
Many patients with difficult asthma also have coexisting vocal cord dysfunction (VCD), evident by paradoxical vocal fold motion (PVFM) on laryngoscopy.
Objective:
Among patients with difficult asthma, we sought to identify clinical features associated with laryngoscopy-diagnosed PVFM.
Methods:
Consecutive patients with "difficult asthma" referred by respiratory specialists underwent systematic assessment in this observational study. Those with a high clinical suspicion for VCD were referred for laryngoscopy, either at rest or after mannitol provocation. Statistical analyses were performed to identify clinical factors associated with PVFM, and a multivariate logistic regression model was fitted to control for confounders.
Results:
Of 169 patients with difficult asthma, 63 (37.3%) had a high clinical probability of VCD. Of 42 who underwent laryngoscopy, 32 had PVFM confirmed. Patients with PVFM more likely had preserved lung function (prebronchodilator forced expiratory ratio 74% ± 11 vs 62% ± 16, P < .001); physiotherapist-confirmed dysfunctional breathing (odds ratio [OR] = 5.52, 95% confidence interval [CI]: 2.4-12.7, P < .001), gastro-oesophageal reflux (OR = 2.6, 95% CI: 1.16-5.8, P = .02), and a lower peripheral eosinophil count (0.09 vs 0.23, P = .004). On multivariate logistic regression, independent predictors for PVFM were dysfunctional breathing (OR = 4.93, 95% CI: 2-12, P < .001) and preserved lung function (OR = 1.07, 95% CI: 1.028-1.106, P < .001).
Conclusion:
Among specialist-referred patients with difficult asthma, VCD pathogenesis may overlap with dysfunctional breathing but is not associated with severe airflow obstruction. Dysfunctional breathing and preserved lung function may serve as clinical clues for the presence of VCD.
More Related Videos
Related Concept Videos
Alterations in Respiration II
In Biot's breathing, the respiratory rate and depth are irregular, alternating between periods of deep gasping and apnea. Common causes...
Respiratory System Abnormal Finding II: Palpation and Auscultation
Palpation Findings
During a respiratory assessment, palpation can reveal several vital abnormalities:
Respiratory System Abnormal Finding I: Inspection and Percussion
Inspection Findings
During an inspection, several findings may suggest the presence of respiratory distress or disease. Pursed-lip breathing, where exhalation is slowed by...
Pulmonary Cycle: Exhalation
Factors Affecting Pulmonary Ventilation
Alveolar Surface Tension
The alveolar fluid lines the luminal surface of the alveoli and exerts a force called surface tension. This force is caused by the polar water molecules in the liquid being more strongly attracted to each...
Breathing

