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Medical AI Inquiry: You were designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.
user
Muller manoeuvre is used in?
assistant
The correct answer is  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)