Cribriform plate

The cribriform plate is the top part of the ethmoid bone, located in the anterior cranial fossa. It acts as a barrier between the nasal cavity and the brain. This plate has numerous tiny holes that enable the olfactory nerves, responsible for smell, to pass through. Its distinct sieve-like appearance is where it gets its name, "cribriform," which means "like a sieve" in Latin. Its positioned horizontally, providing a stable base for the olfactory bulb to sit on.

Shaped like a rectangle, the cribriform plate connects with the surrounding bones to form the floor of anterior cranial fossa. Its front edge meets the frontal bone at a joint known as the frontoethmoidal suture, which has a central marker called the foramen caecum for transmitting an emissary vein. Its rear edge connects with the jugum sphenoidale. The posterolateral corners of the plate have the posterior ethmoidal canals. Its sides join with the orbital plates of the frontal bone, where the anterior ethmoidal canals are found. At the front, the cribriform plate has a midline projection called the crista galli that anchors the falx cerebri, a structure extending into into the brain.

The cribriform plate is quite delicate and can be easily damaged. A break may result in the leakage of cerebrospinal fluid or allow infections to spread from the nasal area to the brain.