Pacchionian foramen means: incisurae tentorii (aka tentorial notch)Clinical Anatomical Terminology, American Association of Clinical Anatomists. a thick opening in the center of the diaphragm of sella through which the infundibulum passes
Due to brain herniation such as supratentorial or infratentorial herniation., the Pacchionian foramen (incisura tentorii) is vital
Tentorium cerebelli The tentorium cerebelli divides the cranial cavity into two closed spaces which communicate with each other through the incisura tentorii. The larger anterior space includes the anterior and middle cranial fossas and lodges the cerebrum; the small posterior space— the posterior cranial fossa contains the cerebellum, the pons, and the medulla.
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