Base of the skull. Upper surface. (On the left, "Anterior ethmoidal foramen" is the 7th label from the right, and "Posterior ethmoidal foramen" is the 9th.
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| colspan="2" |Left maxillary sinus opened from the exterior. (Anterior ethmoidal foramen is labeled at upper left, and posterior ethmoidal foramen is labeled at upper right.
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|colspan="2"|[subject #47 ]
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|MeSH
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|Dorlands/Elsevier
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Lateral to either olfactory groove are the internal openings of the anterior and posterior ethmoidal foramina.
The anterior ethmoidal foramen, situated about the middle of the lateral margin of the olfactory groove, transmits the anterior ethmoidal vessels and the nasociliary nerve; the nerve runs in a groove along the lateral edge of the cribriform plate to the slit-like opening above mentioned.
The posterior ethmoidal foramen opens at the back part of this margin under cover of the projecting lamina of the sphenoid, and transmits the posterior ethmoidal vessels and nerve.
