cochlear aqueduct

In addition, the assumption that the pressure of perilymph is equal to ICP does not hold if the patency of the cochlear aqueduct is compromised, which is often the case in elderly subjects.

Because cerebrospinal fluid and perilymph communicate through the cochlear aqueduct, an increase in intracranial pressure is directly transmitted to the footplate of the stapes, changing its initial position and affecting thereby the direction and magnitude of the displacement of the eardrum in response to a sound.