Quick Facts
Origin: The optic disk in the retina.
Course: Runs posteriorly from the posterior margin of the eye, through the optic canal, and into the cranium.
Branches: Merges with the contralateral optic nerve at the optic chiasm.
Supply: Conveys visual information towards the cortex.
Related parts of the anatomy
Origin
The optic nerve forms when the axons of retinal ganglion cells converge at the back of the eyeball at the optic disk.
Course
The optic nerve emerges from the posterior margin of the eye and runs posteriorly through the orbit. It exits the orbit through the optic canal, emerging intracranially in the middle cranial fossa.
Branches
The optic nerve does not branch. However, it merges with the contralateral optic nerve at the optic chiasm, where some fibers decussate while others remain ipsilateral.
Supplied Structures
The optic nerve is a sensory nerve. It conveys all visual information from the retina towards the cerebral cortex. Most of its axons will travel to the lateral geniculate nucleus and then on to primary visual cortex. Additional axons will travel to the superior colliculus, suprachiasmatic nucleus, and pretectal nuclei.
List of Clinical Correlates
—Visual deficits
—Pupillary light reflex deficits
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