Left temporal bone. Inner surface. (Mastoid foramen labeled at bottom right.)
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| colspan="2" |Base of the skull. Upper surface. (Temporal bone is pink, and label for mastoid foramen is at left, second from the bottom.)
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|Latin
|colspan="2"|foramen mastoideum
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|colspan="2"|[subject #34 ]
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|System
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|Precursor
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|MeSH
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|Dorlands/Elsevier
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The outer surface of the temporal bone is perforated by numerous foramina; one of these, of large size, situated near the posterior border, is termed the mastoid foramen; it transmits a vein to the transverse sinus and a small branch of the occipital artery to the dura mater.
The position and size of this foramen are very variable; it is not always present; sometimes it is situated in the occipital bone, or in the suture between the temporal and the occipital.
