Tympanometry of an adult with autophony and aural fullness shows a well-defined peak shifted markedly to the negative side, with peak pressure at minus 220 daPa. This tympanogram is classified as:
- A Type A
- B Type C ✓
- C Type B
- D Type Ad
Correct answer: B. Type C
Explanation
A Type B curve retains normal compliance and a clear peak but the point of maximum admittance lies at abnormally negative middle ear pressure, conventionally beyond minus 100 daPa. This reflects impaired eustachian tube function with relative vacuum in the middle ear, and may precede effusion. Type C is flat with no measurable peak, while Type A has its peak near atmospheric pressure.
Reference: Dhingra's Diseases of Ear, Nose and Throat, 8th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.