Vocal cord dysfunction: what do we know?

Vocal cord dysfunction (VCD) is a disorder caused by episodic unintentional paradoxical adduction of the vocal cords, which may induce acute severe dyspnoea attacks not responsive to conventional asthma therapy. The aetiology of VCD is complex and often multifactorial. The essential pathophysiology is that of a hyperfunctional laryngeal reflex to protect the lower airway as a result of any combination of post-nasal drip, gastro-oesophageal reflux, laryngopharyngeal reflux and/or psychological conditions. Laryngoscopic demonstration of the paradoxical motion while wheezing or stridorous is considered the diagnostic gold standard. Speech therapy, including the use of special relaxed-throat breathing patterns is effective for VCD that is purely of the functional nature. Knowledge of the clinical features of VCD and identifying factors that may be contributing to the development of VCD can provide adequate clues to the correct diagnosis and management.