Geng et al. subdivided the dorsum sellae meningiomas into two groups

Type 1 (dorsum sellae, inferior third ventricle type)

Type 2 (dorsum sellae, third ventricular type), depending upon the site and direction of growth ^{1) 2) 3)}.

Lesions in this region are primarily of two anatomic types:

Centrally placed meningiomas located between the two posterior clinoid processes (PCPs) and arising from the dorsum sellae or upper clival region – which should be referred to as dorsum sellae or upper clival meningiomas.

Eccentrically placed meningiomas centered on the PCP are true posterior clinoid process meningiomas ⁴⁾.