Those processes are connected by a horizontal fold of dura mater described as interclinoid dural fold or interclinoid ligament
. On a lateral cephalometric radiograph the image of sella turcica is U shaped.
The fusion of anterior and posterior clinoid processes or a calcification of interclinoid ligament termed as STB (Shah et al., Kucia et al.).
The interclinoid ligament bisects the wall of the cavernous sinus, dividing it into two triangles; carotid trigone anteromedially and occulomotor trigone posterolaterally.
Nomenclature Variation for STB interclinoid taenia interclinoid bars interclinoid osseous bridge sella turcica bridge/bridging sella bridge roofing / bulging / calcification of the diaphragma sellae calcified / ossified interclinoid ligament Table III.
The presence of ossified interclinoid ligament makes the removal of the anterior clinoid process more difficult and increases the risks especially in the presence of an aneurysm.
The carotico-clinoid and interclinoid ligaments are related to the internal carotid artery and oculomotor nerve.
Surgical removal of the anterior clinoid processes to expose of the structures of the cavernous sinus is more difficult when the interclinoid ligament is ossified, due to the established neural and vascular relationships (oculomotor, trochlear, abductor, ophthalmic and mandibular nerves, internal carotid artery, cavernous sinus and coronary sinus) (Ozdogmus et al., 2003).
Ossification of interclinoid ligament and its clinical Significance.
Along with the pterygospinous, pterygoalars and carotico-clinoid ligaments, the interclinoid ligaments comprise a group of intrinsic ligaments of the sphenoid bone.