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Updated: Aug 15, 2026

Investigating the Three-dimensional Flow Separation Induced by a Model Vocal Fold Polyp
Published on: February 3, 2014
Atypical expiratory flow volume curve in an asthmatic patient with vocal cord dysfunction
A H Bahrainwala1, M R Simon, D D Harrison
1Division of Immunology, Allergy and Rheumatology, Children's Hospital of Michigan, Detroit 48201, USA. abahrain@pol.net
Background:
Vocal cord dysfunction can coexist with or masquerade as asthma. Vocal cord dysfunction, when coexistent with asthma, contributes substantially to the refractory nature of the respiratory problem.
Objective:
To report a case of an asthmatic patient with vocal cord dysfunction and a previously unreported unique expiratory flow volume curve.
Results:
A 16-year-old female, known to have asthma, developed increased frequency of her asthma exacerbations. Spirometry, during symptoms, showed an extrathoracic airway obstruction with a reproducible unique abrupt drop and rise in the expiratory flow volume loop. Laryngoscopy showed adduction of the vocal cords during inspiration and expiration.
Conclusions:
We report a unique expiratory flow volume curve in an asthmatic with vocal cord dysfunction that resolved with panting maneuvers. Speech and psychological counseling helped prevent future attacks.
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