The ciliary ganglion in man (anatomical observations).

In 30 human orbits the ciliary ganglion with its motor (parasympathetic), sympathetic and sensory roots and the short ciliary nerves were dissected under the surgical microscope. The ganglion was situated near the orbital apex, between the optic nerve, abducens nerve, lateral rectus muscle and the ophthalmic artery. In 2 cases the motor, parasympathetic root was missing and the ganglion was attached directly to the inferior branch of the 3rd nerve or to the nerve of the inferior oblique muscle. In some cases the root was double. The sensory root was very constant. The sympathetic root was identified only in 22 specimens. It took origin from the sympathetic carotid plexus; in a few cases from the sympathetic plexus around the ophthalmic artery or from both sources. Most of the short ciliary nerves entered the eyeball in its temporal aspect. Only 1-2 short ciliary nerves entered the medial aspect after crossing the inferior of the optic nerve. In 2 cases, additional short ciliary nerves originated directly from the motor root, and in one case from the sensory root. Connections between short and long ciliary nerves were also observed. In order to locate the ganglion it is advised to find first the nerve to the inferior oblique muscle, along the inferior border of teh lateral rectus, and follow it backwards up to the motor root.