How does tympanometry relate to ear infections?

Fluid detection: In infancy the retention of normal middle ear mucous is common if it doesn't drain out of the eustachian tube. That fluid can become infected if germs invade up the tube to the middle ear. Tympanometry can provide evidence for the presence or absence of fluid through detecting the resilience of the ear drum. If no fluid is detected, no middle ear infection will be present.