anterior ethmoidal foramen anterior ethmoidal foramen the anterior ethmoidal foramen is a small opening in the ethmoid bone in the skull. anterior ethmoidal foramenbase of the skull. upper surface. (on the left, "anterior ethmoidal foramen" is the 7th label from the right.)1 foramen ethmoidale, 2 canalis opticus, 3 fissura orbitalis superior, 4 fossa sacci lacrimalis, 5 sulcus infraorbitalis, 6 fissura orbitalis inferior, 7 foramen infraorbitaledetailsidentifierslatinforamen ethmoidale anteriusta98a02.1.00.079ta2484fma53135anatomical terms of bone lateral to either olfactory groove are the internal openings of the anterior and posterior ethmoidal foramina (or canals). the anterior ethmoidal foramen, situated about the middle of the lateral margin of the olfactory groove, transmits the anterior ethmoidal artery, vein and nerve. the anterior ethmoidal nerve, a branch of the nasociliary nerve, runs in a groove along the lateral edge of the cribriform plate to the above-mentioned slit-like opening .