middle clinoid process
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middle clinoid process[TA]
an inconstant, small spur of bone on the body of the sphenoid, posterolateral to (and occasionally continuous with) the tuberculum sellae; it is around this point that the internal carotid artery makes a 180-degree turn, changing direction from anterior to posterior to join the cerebral arterial circle.
Synonym(s): processus clinoideus medius [TA]