Keros Classification

Classifies the depth of the olfactory fossa defined as follows:

• Keros I: 1-3mm 
• Keros II: 3-7mm 
• Keros III: 7-16mm

Keros P. [On the practical value of differences in the level of the lamina cribrosa of the ethmoid]. Z Laryngol Rhinol Otol. 1962;41:809-13.

Contributor: Alex Goel, MD