Hello XXXXXXX
Thanks for the query.

Mastoid air cells are air spaces found in the temporal bone which houses the ear. They are an interconnected network of small cavities which communicate with the middle ear.
The middle ear is bordered by the tympanic membrane which prevents it from communicating with the external environment thus the middle ear relies on the compliance of the air-filled mastoid air cells in order to allow the tympanic membrane to move freely in order to convert external pressure in to vibrations of bony structures which in turn convey the motion to the inner ear from where they are interpreted as sound.
In a case where the mastoid air cells are absent or fluid filled, there is less compliance in the above system, thus the ability for the tympanic membrane to move and transmit sound is reduced and consequently there is reduced auditory acuity.
The mastoid air cells are also known to secret fluid that slowly travel from the mastoid air cells through the middle ear and into the posterior nasopharynx through the eustachian tubes in order to keep the middle ear clear of debris.

Hope this answers your query. If you have more query, i will be waiting to respond.
Best regards.

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Hello XXXXXXX
thanks once more for the query,

At birth, the air spaces are not present but they gradually develop within the first year of life and it is possible for the air cells to fail to develop which will lead to poor auditory acuity and in some cases ringing. Headache is not associated to this unless there is an infection or resulting from stress due to ringing.

In the case of mastoiditis ( infection of the mastoid) the air spaces could become filled. However mastoiditis presents with pains and swelling behind the affected ear and is associated with fever, headaches and ear ringing (tennitus).

Hope this answers your query. If you do not have further query you could close the discussion and rate the answers.
Best regards

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