Intercavernous sinuses
The intercavernous sinuses are two in number, an anterior and a posterior, and connect the two cavernous sinuses across the middle line.
The anterior passes in front of the hypophysis cerebri, the posterior behind it, and they form with the cavernous sinuses a venous circle around the hypophysis.
The anterior one is usually the larger of the two, and one or other is occasionally absent.
