As part of the history, you may be asked to fill out validated questionnaires related to voice and chronic cough. This will help us assess the severity of your symptoms and provide us with a baseline against which to compare improvement from therapeutic interventions.
An examination of the larynx via nasal endoscopy is very important to exclude growths on the vocal folds (VFs) that may be triggering the cough. It will also demonstrate stigmata of other conditions like laryngopharyngeal reflux. Examination of vocal fold motion whilst breathing may in some cases demonstrate dys-coordinated vocal fold opening with respiration (normally the vocal folds move apart when you breathe in or out) called paradoxical vocal fold motion. Other more subtle motion defects can only be visualised after performing video stroboscopy which we perform routinely when assessing the larynx.
You may also require allergy testing and certain specific blood tests depending on the potential cause(s).
A high-resolution CT scan of the neck and chest may be requested to aid diagnosis. Occasionally this may demonstrate a narrowing in the airway just below the vocal folds, which may warrant further investigations and specific surgical management.
A CT scan of the paranasal sinuses will help diagnose chronic rhinosinusitis.
If there is concern about aspiration then a video swallow assessment may be useful. This is a dynamic X-ray study which looks at how a swallowed radio-dense dye passes through and around the larynx and upper swallowing apparatus.
As conditions pertinent to gastroenterology and respiratory medicine may contribute to or indeed cause the cough, you may be referred to a gastroenterologist or respiratory physician for further investigations and management. These may include an ambulatory pH study, a gastric endoscopy and lung function testing.