Ciliary ganglion

The ciliary ganglion is a small parasympathetic ganglion located within the orbit, laterally to the optic nerve. The ganglion receives three types of nerve fibers: parasympathetic, sympathetic, and sensory.

Its parasympathetic root comes from the parasympathetic nucleus of the oculomotor nerve, and the sympathetic fibers originate from the cranial cervical ganglion, via the internal carotid plexus and the branches that the cavernous plexus sends to the trigeminal nerve, and then passes via a branch of the nasociliary nerve.

The ciliary ganglion belongs to the parasympathetic system. It delegates the very thin short ciliary nerves, which join the optic nerve and accompany it to reach the eyeball by penetrating the sclera.