On impedance audiometry, a Type B tympanogram (flat, no peak) with very low static compliance and large ear canal volume most likely indicates:

• A Tympanic membrane perforation ✓
• B Middle ear effusion (otitis media with effusion)
• C Otosclerosis
• D Ossicular discontinuity

Explanation

A flat Type B tympanogram with very HIGH ear canal volume (>2 ml in adults) indicates a perforated tympanic membrane (or patent ventilation tube), as the probe is measuring a combined large volume (ear canal + middle ear space). A Type B with NORMAL or low canal volume indicates middle ear effusion (fluid restricts tympanic membrane movement). Type As (low compliance) suggests otosclerosis or tympanosclerosis. Type Ad (high compliance, high peak) indicates ossicular discontinuity or a very flaccid tympanic membrane.

Reference: Dhingra Diseases of Ear, Nose and Throat, 7th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.