[Compression and obstruction of the internal carotid artery by sellar and parasellar tumors]

It is classicaly admitted that the intracranial internal carotid artery after a first intracavernous segment, becomes intra-dural by perforating or passing through the dura. Since 1949, the first of us has refuted this conception as well as that of the artery floating in the venious blood of the cavernous sinus and has described to so-called cavernous sinus as a latero-seller extradural space into which the artery has but neighbourhood relationship with a venous plexus. During embryonic development the internal carotid artery is englobed by the dura which differentiates around the cerebral vessels. At a later stage, owing to the adhesion of the dural leaf to the intracranial periosteum, the internal carotid artery becomes closely attached to the bone at the level of the base of the anterior clinoid process. This explains that tumors developping in the sellar and parasellar region may compress or obstruct the carotid artery at this level causing neurologic symptoms of ischemic origin. Three similar cases are reported, a glioma of the optic nerve, an adenoma of the hypophysis and meningioma of the sphenoidal wing.