C-shaped curve on tympanometry is seen in: (A) Serous otitis media, (B) Otosclerosis, (C) TM perforation, (D) Eustachian tube obstruction
Answer is D. Type C: Max compliance occurs with negative pressure in excess of 100mm H2O Seen in retracted TM Also some fluid present in the middle ear. Ref: Dhingra; 6th Edition; pg no 24