What is the probable diagnosis in the patient with below flow volume loop (FVL)?: (A) Restrictive airway disease, (B) Tracheal stenosis, (C) Obstructive airway disease, (D) None of the above
Answer is B. The above FVL is a typical of fixed central airway obstruction (Either above or below the thoracic inlet) such as tracheal stenosis. In this, there is limitation to peak flow rate,Flattened inspiratory and expiratory curves are seen. Other FVL patterns: 1.Normal 2. Airflow obstruction:- COPD 3. Fixed Upper Airway obstruction 4.Variable upper airway obstruction 5.