Horner's Syndrome and Autonomic innervation of the eye

The internal carotid plexus is situated on the lateral side of the

internal carotid artery The internal carotid artery (Latin: arteria carotis interna) is an artery in the neck which supplies the anterior circulation of the brain. In human anatomy, the internal and external carotids arise from the common carotid arteries, where these ...

, and in the plexus there occasionally exists a small gangliform swelling, the ''carotid ganglion'', on the under surface of the artery. Postganglionic sympathetic fibres ascend from the superior cervical ganglion, along the walls of the internal carotid artery, to enter the internal carotid plexus. These fibres then distribute to deep structures, which include the Superior Tarsal Muscle and pupillary dilator muscles. Some of the fibres from the internal carotid plexus converge to form the

deep petrosal nerve The deep petrosal nerve is a branch of the internal carotid plexus which runs through the carotid canal lateral to the internal carotid artery. It enters the cartilaginous substance which fills the foramen lacerum, and joins with the greater petros ...

.Richard L. Drake, Wayne Vogel & Adam W M Mitchell, "Gray's Anatomy for Students", Elsevier inc., 2005 The internal carotid plexus communicates with the

trigeminal ganglion A trigeminal ganglion (or Gasserian ganglion, or semilunar ganglion, or Gasser's ganglion) is the sensory ganglion at the base of each of the two trigeminal nerves (CN V), occupying a cavity ( Meckel's cave) in the dura mater, covering the tri ...

, the

abducent nerve The abducens nerve or abducent nerve, also known as the sixth cranial nerve, cranial nerve VI, or simply CN VI, is a cranial nerve in humans and various other animals that controls the movement of the lateral rectus muscle, one of the extraocula ...

, and the

pterygopalatine ganglion The pterygopalatine ganglion (aka Meckel's ganglion, nasal ganglion, or sphenopalatine ganglion) is a parasympathetic ganglion found in the pterygopalatine fossa. It is largely innervated by the greater petrosal nerve (a branch of the facial ner ...

(also named sphenopalatine); it distributes filaments to the wall of the

, and also communicates with the tympanic branch of the

glossopharyngeal nerve The glossopharyngeal nerve (), also known as the ninth cranial nerve, cranial nerve IX, or simply CN IX, is a cranial nerve that exits the brainstem from the sides of the upper medulla, just anterior (closer to the nose) to the vagus nerve. ...

Additional images

File:Gray777.png, Nerves of the orbit, and the ciliary ganglion. Side view. File:Ciliary ganglion pathways.png, Pathways in the Ciliary Ganglion.

References

;Notes Nerve plexus {{Neuroanatomy-stub