- TYPE A - normal shape reflects a normal mechanism
- Type B - No sharp peak, with little or no variation in impedance over a wide range:
- Type C - Peak compliance is significantly below zero, indicating negative pressure (sub-atmospheric) in the middle ear space. This finding is often indicative of eustachian tube dysfunction.
- Type D: Notching: shows a dip in the peak. Indicates scarred eardrums or hypermobile TM