Lateral lamella

The lateral lamella (also known as the lamina lateralis) is the name given to the lateral boundary of the cribriform plate of the ethmoid bone. It runs vertically and joins the fovea ethmoidalis inferomedially. It is the thinnest part of the cribriform plate.

Practical points

The lateral lamella needs to be assessed on pre-functional endoscopic sinus surgery (FESS) imaging studies. If one of the lateral lamellae is inferiorly positioned, this should be reported as this poses a greater risk of intraoperative injury. Its height is quantified indirectly via assessment of the depth of the olfactory fossa (Keros classification).