Where is mastoid sinus

Mastoiditis is infection and inflammation of the mastoid. The mastoid bone is located behind the ears. If you slide your hand up the neck behind the ear you will feel it as a bony prominence. The inside of the mastoid bone is aerated. This means that it is hollow. It is not like the long bones of the extremities that are solid. It is more like the bones of the face which house the sinuses. In fact, the mastoid is essentially the sinus of the ear.

Sound resonates in the air-filled spaces of the ear including the mastoid. The spaces are lined with mucosa like the lining of your mouth, lungs, or stomach. Similar to a sinus infection or ear infection, mastoiditis occurs when bacteria infect the lining of the mastoid. However, these infections are less common than sinusitis or otitis. Mastoiditis can be divided into different types such as acute mastoiditis, chronic mastoiditis, serous mastoiditis, and radiologic mastoiditis.

When doctors use the term mastoiditis without specifying a type, they are referring to acute mastoiditis. Serous mastoiditis refers to sterile fluid in the mastoid. This occurs in children and adults with Eustachian tubes that do not effectively ventilate the ear and mastoid.

Sometimes these situations lead to inflammation and remodeling of the ear and mastoid. This occurs over months to years. This is called chronic mastoiditis and may be associated with cholesteatoma. Acute mastoiditis is bacterial infection of the mastoid. Imaging such as CT scan cannot always distinguish the types. Undistinguished mastoiditis based on imaging is called radiologic mastoiditis.

Acute mastoiditis causes ear symptoms and systemic symptoms. Mastoid air cells communicate with the middle ear via the mastoid antrum and the aditus ad antrum. The mastoid air cells are traversed by the Koerner septum , a thin bony structure formed by the petrosquamous suture that extends posteriorly from the epitympanum, separating the mastoid air cells into medial and lateral compartments.

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Check for errors and try again. Thank you for updating your details. Log In. Sign Up. Become a Gold Supporter and see no ads. Log in Sign up. Articles Cases Courses Quiz. About Recent Edits Go ad-free. Edit article. View revision history Report problem with Article. Citation, DOI and article data. Our doctor will examine your ears with an otoscope, looking for signs of infection.

Many cases of mastoiditis are treated successfully with antibiotics. Chronic cases may require frequent visits for thorough ear cleanings. When antibiotics fail to treat the problem adequately, or it recurs frequently, surgery may be necessary. Mastoid surgery, or mastoidectomy, involves drilling a hole in the mastoid bone and removing the infected air cells. This procedure is performed under general anesthesia, and many patients return home later the same day.

Afterwards, your ears will be bandaged, and there may be stitches.