Muller manoeuvre is used in?
High-Yield Explanation
Muller's manoeuvre: A flexible endoscope is passed through the nose and the patient asked to inspire vigorously with nose and mouth completely closed. Look for the collapse of the soft tissues at the level of the base of the tongue and just above the soft palate. Level of pharyngeal obstruction can be found. (Ref: Diseases of ENT, PL Dhingra, 7th edition, pg no. 315)