Tympanometry of a 12-year-old with nasal obstruction and recurrent ear fullness shows a tympanogram with a normal-height peak shifted to the negative pressure side, peaking at -250 daPa. This is classified as:
- A Type A
- B Type C ✓
- C Type B
- D Type As
Correct answer: B. Type C
Explanation
A Type B tympanogram has a discernible peak but at abnormally negative middle ear pressure, conventionally beyond -100 to -150 daPa, reflecting impaired eustachian tube ventilation of the middle ear cleft. Compliance remains normal, distinguishing it from Type As where peak height is reduced. Type C is flat with no measurable peak, seen in effusion or perforation, so it does not fit this tracing.
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.