Optic nerve at a glance
- What it is
- The optic nerve (CN II) carries visual information from the retina to the brain.
- Location
- It extends from the back of the eyeball through the orbit and optic canal into the middle cranial fossa to the optic chiasm.
- Function
- It is purely sensory and consists of retinal ganglion cell axons that transmit visual signals.
- Body system
- Nervous · paired (left and right)
- FMA ID
- FMA50878 (Foundational Model of Anatomy)
Key facts
- Cranial nerve II.
- Is part of the central nervous system and surrounded by meninges.
- Contains about 1 million axons.
- The central retinal artery and vein run within its front part, entering about 1 cm behind the eyeball.
Clinical relevance
Optic neuritis causes visual loss and pain with eye movement, and raised intracranial pressure may cause papilloedema.
Structures next to the optic nerve
The nearest named structures in the 3D model, measured from the centre of each part:
- Communicating branch of nasociliary nerve with ciliary ganglion · nervous
- Frontal nerve · nervous
- Superior branch of oculomotor nerve · nervous
- Ciliary ganglion · nervous
- Ophthalmic artery · cardiovascular
- Long ciliary nerve · nervous
- Trochlear nerve · nervous
- Inferior branch of oculomotor nerve · nervous
- Anterior ethmoidal nerve · nervous
- Superior rectus · muscular
References
- Foundational Model of Anatomy: Optic nerve (FMA50878). EMBL-EBI Ontology Lookup Service.
- OpenStax. Anatomy and Physiology 2e, §12.1 Basic Structure and Function of the Nervous System. Rice University, 2022.
- Mitsuhashi N. et al. (2009). BodyParts3D: 3D structure database for anatomical concepts. Nucleic Acids Research 37, D782–D785. Data © The Database Center for Life Science, CC BY 4.0.
Related anatomy
Explore the whole body in the interactive 3D human anatomy model, or browse the A–Z list of human structures.