What is indicated by a Type C tympanogram?

A Type C tympanogram is indicative of significant negative pressure in the middle ear while normal compliance is maintained in the tympanic membrane. This condition typically suggests that there is an issue with eustachian tube function, where the pressure in the middle ear is lower than that of the external ear canal.

In the case of a Type C tympanogram, you might observe a peak that occurs at negative pressure, confirming that the ear is attempting to maintain an appropriate amount of air pressure but is not fully able to do so. This can occur with conditions such as a cold or allergies when eustachian tube dysfunction is present.

This is different from the other options, which indicate different states of ear health and pressure relationships. Fluid in the middle ear would generally lead to a Type B tympanogram, characterized by flat compliance readings. Normal ear function would align with a Type A tympanogram, showing a peak at atmospheric pressure with normal compliance. Therefore, understanding the characteristics of a Type C tympanogram is essential for identifying eustachian tube dysfunction and potential related pathologies.