Nerve pathways between the pterygopalatine ganglion and eye in cats

By dissection of thiocholine-stained orbital preparations, it has been determined that three different nerve pathways link the pterygopalatine ganglion and the eye in cats. 1) Nerves from the proximal half of the ganglion join a plexus of nerves and ganglion cells in the rete mirabile of the maxillary artery. Branches of the internal carotid nerve also supply this plexus. Fine nerves from the plexus travel to the optic nerve and then to the eye, accompanying both the nasociliary nerve that passes through the rete and the ciliary arteries that arise from the rete. 2) One or more nerves from the nerve of the pterygoid canal and from a prominent accessory ganglion near the orbital apex course to the inferior optic nerve surface at the optic foramen; these then run distally along the optic nerve to fuse with ciliary nerves or to accompany ciliary arteries entering the eye. 3) Other nerves from the pterygopalatine ganglion travel medially around the extraocular muscle cone to join the ethmoidal and infratrochlear branches of the nasociliary nerve; some nerves from the ganglion then take a retrograde course to the optic nerve, where they join ciliary nerves or arteries to the eye. All three pathways may transmit sympathetic, parasympathetic and somatic sensory nerve fibers.