Gyrus Perforatum of the Olfactory Brain

The gyrus of the perforated olfactory brain (G.perforatus rhinencepalium) is a deep hole at the junction of the upper edge of the sphenoid sinus and the gyrus of the same name. It is bounded medially and inferiorly by the cribriform plate, and laterally by the medial alar plates of the sphenoid bones. Its dimensions are different and vary from person to person. In newborns, the length of the gyrus is 3 cm, in an adult it is 6-7 cm, and the width is 2.5-3 mm. It is a continuation of the lateral olfactory lobe and enters the middle cranial fossa. The gyrus is deep and wide, and at the top it is much wider in diameter than at the bottom: in children it is 7-8 mm long and 3-4.5 mm wide; by adulthood its dimensions grow to 8-9 mm and 5 mm, respectively. From above, the gyrus is covered with the dura mater (arachnoid) and passes further to the temporal lobe along the lower wall of the temporal fossa. Below the temple, the gyrus becomes wedge-shaped nodular. Medially, it communicates with the lateral olfactory sulcus and with the medial end of the pinnacle of the olfactory nerve, where the latter passes through it, exiting the face along the upper wall of the orbit (through the round