Crista galli

The crista galli is a thick, midline, smooth triangular process arising from the superior surface of the ethmoid bone, projecting into the anterior cranial fossa. It separates the olfactory bulbs, which lie either side of it in the olfactory fossae of the cribriform plate. It serves as an anterior attachment for the falx cerebri. Immediately lateral to it are the nasal slits where the anterior ethmoidal nerves descend into the roof of the nasal cavity.

The crista galli may contain marrow or be pneumatized. On MRI, it may, therefore, appear T1 hyperintense if it contains marrow, or have low signal and mimic a mass if pneumatized.

At birth, the anterior skull base is largely cartilaginous. Ossification of crista galli and perpendicular plate of the ethmoid bone begins around 2 months of age.

History and etymology

Crista galli is Latin for rooster's crest.