Which test uses air pressure changes in the ear canal?

Which test uses air pressure changes in the ear canal?

• A. Tympanometry
• B. Acoustic reflectometry
• C. Audiometer
• D. Otoscope

Answer: (A)

Tympanometry measures how the middle ear responds to changes in air pressure in the ear canal. A probe in the ear canal seals the canal and systematically varies the pressure while a tone is played. By watching how easily the tympanic membrane moves (its compliance) as pressure changes, the test reveals the pressure in the middle ear and how well the eardrum conducts sound. A normal curve shows peak mobility near ambient pressure, indicating a healthy middle ear. If the curve is flat or shows a peak at negative pressure, it points to problems like fluid in the middle ear or Eustachian tube dysfunction. This is distinct from the other tests: acoustic reflectometry uses sound reflections to gauge middle-ear status without a pressure sweep; an audiometer tests hearing thresholds with tones; an otoscope visually inspects the ear.

Tympanometry measures how the middle ear responds to changes in air pressure in the ear canal. A probe in the ear canal seals the canal and systematically varies the pressure while a tone is played. By watching how easily the tympanic membrane moves (its compliance) as pressure changes, the test reveals the pressure in the middle ear and how well the eardrum conducts sound. A normal curve shows peak mobility near ambient pressure, indicating a healthy middle ear. If the curve is flat or shows a peak at negative pressure, it points to problems like fluid in the middle ear or Eustachian tube dysfunction. This is distinct from the other tests: acoustic reflectometry uses sound reflections to gauge middle-ear status without a pressure sweep; an audiometer tests hearing thresholds with tones; an otoscope visually inspects the ear.