From the case:
Anterior ethmoidal notch
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Bilateral anterior ethmoidal notches. "Protected" on the right (red arrow). At increased risk of injury on the left (yellow arrow) due to supraorbital ethmoidal air cell pneumatization.
Case Discussion
Original case courtesy of Dr Yair Glick, Radiopaedia.org, rID: 53200.
URL: https://radiopaedia.org/cases/normal-paranasal-sinuses-and-petrous-temporal-bones
Modifications: crop and annotation.
Licence: Creative Commons.