Ramus sympathetica ganglii ciliaris

The Ramus sympathetica ganglii ciliaris is a component of the autonomic nervous system that provides sympathetic innervation to the ciliary ganglion. This structure plays a crucial role in the pupillary light reflex and the accommodation reflex of the eye.

Structure

The ramus sympathetica ganglii ciliaris consists of postganglionic sympathetic fibers that originate from the superior cervical ganglion. These fibers travel along the internal carotid artery and enter the cavernous sinus, where they join the ophthalmic division of the trigeminal nerve (CN V1). The fibers then reach the ciliary ganglion without synapsing.

Function

The primary function of the ramus sympathetica ganglii ciliaris is to mediate the dilation of the pupil (mydriasis) in response to low light conditions or sympathetic stimulation. This is achieved by innervating the dilator pupillae muscle of the iris.

Clinical significance

Damage or disruption to the ramus sympathetica ganglii ciliaris can result in Horner's syndrome, which is characterized by ptosis, miosis, and anhidrosis. This condition can occur due to lesions affecting the sympathetic pathway at any point from the hypothalamus to the ciliary ganglion.

See also

• Ciliary ganglion
• Autonomic nervous system
• Pupillary light reflex
• Accommodation reflex