Just before the n. maxillaris exits the fossa media cranii via the foramen rotundum, it gives off a small r. meningeus which carries sensory impulses from the dura mater of this region. Within the fossa pterygopalatina, the n. maxillaris gives off a number of branches that can be divided into those which arise directly from the nerve and those associated with the ggl. pterygopalatinum which is located on the posterior wall of the fossa pterygopalatina (see next image). The n. maxillaris leaves the fossa pterygopalatinum by coursing forward through the fissura pterygomaxillaris to enter the infratemporal fossa, where it gives off the n. alveolaris superior posterior. It then turns medially to enter the orbit via the fissura orbitalis inferior, where it continues as the terminal branch of the n. maxillaris, the n. infraorbitalis. The n. infraorbitalis proceeds anteriorly across the floor of the orbit in the infraorbital groove, giving off the n. alveolaris superior medius, before continuing through the canalis infraorbitalis. Here, the n. alveolaris superior anterior nerve arises before the n. infraorbitalis continues onto the face and terminates as groups of rr. palpebrales, rr. nasales and rr. labiales superiores.
