What is the clinical significance of the mastoid air cells?
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The mastoid air cells are thought to protect the delicate structures of the ear, regulate ear pressure and possibly protect the temporal bone during trauma. When the mastoid cells become infected or inflamed, often as a result of an unresolved middle ear infection (otitis media), mastoiditis can develop.
What does mastoid air cells mean?
The mastoid cells (also called air cells of Lenoir or mastoid cells of Lenoir) are air-filled cavities within the mastoid process of the temporal bone of the cranium. The mastoid cells are a form of skeletal pneumaticity. Infection in these cells is called mastoiditis.
What does a CT of the mastoid show?
In suspected cases of AM, computerised tomography (CT) of the temporal bone can be a helpful aid for diagnosis and evaluation of potential complications. CT imaging can display information on the state of the middle ear cavity, the mastoid air cells and evaluate for intra- and extra-cranial complications.
What CT scan shows mastoiditis?
CT scanning of the temporal bone is the standard for evaluation of mastoiditis, with published sensitivities ranging from 87-100%.
What causes mastoid air cells?
Mastoiditis is usually caused by a middle ear infection (acute otitis media). The infection may spread from the ear to the mastoid bone of the skull. The mastoid bone fills with infected materials and its honeycomb-like structure may deteriorate. Mastoiditis usually affects children.
What are the types of mastoid air cells?
Agger nasi, Haller’s cells and Onodi cells are some variants described. The mastoid pneumatization and its measurement has also been studied earlier [3, 4].
What causes fluid in the mastoid air cells?
Ear infections or disease in the ear or elsewhere can cause those spaces to fill with fluid, mucus or excess tissue (such as a cholesteatoma, a benign tumor that may grow out of a healing perforated ear drum and cause hearing damage).
How is the tympanic cavity connected to the mastoid antrum?
Via the aditus ad antrum the tympanic cavity is connected to the mastoid antrum, which is a large aircell superiorly and posteriorly to the tympanic cavity, and communicates with the mastoid air cells.
Are mastoid air cells always present in the middle ear?
Occasionally, they are entirely absent. Mastoid air cells communicate with the middle ear via the mastoid antrum and the aditus ad antrum .
What does a CT scan of the tympanic cavity show?
Axial CT scan in bone window shows opacification in tympanic cavity and destruction of mastoid air cells, caused by glomus jugulotympanicum (arrows) For the most efficient communication with ENT surgeons, GTP should be evaluated according to Glasscock-Jackson classification [31] (TableĀ 4).
Where is the tympanic cavity located in the ear?
The tympanic cavity is the major portion of the middle ear and contains the ossicles. Via the aditus ad antrum the tympanic cavity is connected to the mastoid antrum, which is a large aircell superiorly and posteriorly to the tympanic cavity, and communicates with the mastoid air cells.