sellar diaphragm

di·a·phrag·ma sel·'lae

[TA]
a fold of dura mater extending transversely across the sella turcica and roofing over the hypophyseal fossa; it is perforated in its center for the passage of the infundibulum.

sellar diaphragm

a dural partition consisting of a small horizontal shelf of meningeal dura mater that covers the hypophysial fossa in the sella turcica of the sphenoid bone. Also called diaphragma sellae.