1. Nerves of the orbit

2. CN II Enters via optic canal Covered by meninges 25 mm in orbit
Pierces sclera 3mm lateral to posterior pole

4. Crossed by [lateral to medial] ophthalmic artery, nasociliary nerve, superior ophthalmic vein
Ciliary ganglion is a lateral relation

5. Infraorbital nerve Enters via superior orbital fissure
Lies in a groove in posterior part of orbital floor

6. Area supplied Maxillary sinus Some upper teeth Lower lid Cheek Nose
Upper lip
Labial gums

8. Zygomatic nerve Runs in lateral wall
Divides into zygomaticofacial and zygomaticotemporal branches
Zygomaticotemporal nerve gives communicating branch to lacrimal nerve→ lacrimal gland [secretomotor fibres]

9. Lacrimal nerve Runs on upper border of lateral rectus
Receives secretomotor branch from zygomaticotemporal nerve→ lacrimal gland

10. Frontal nerve Large main branch of CN V1
Runs above levator palpebrae superioris
Divides into supratrochlear and supraorbital branches

11. Nasociliary nerve Crosses lateral to medial above CN II
Lies behind ophthalmic artery
Continues as anterior ethmoidal nerve→ nasal cavity

12. Other branches
Infratrochlear → lacrimal sac, conjunctiva, upper lid, bridge of nose
Posterior ethmoidal
To ciliary ganglion
Long ciliary →ciliary body, iris, cornea- also carries postganglionic fibres from Superior cervical ganglion to dilator pupillae

13. Ciliary ganglion
Sensory root – branch from nasociliary nerve- no synapse
Sympathetic root – from internal carotid plexus- no synapse [vasoconstrictor fibres]
Parasympathetic root from nerve to inferior oblique [cell bodies in Edinger-Westphal nucleus]- synapse→ ciliary body, sphincter pupillae

14. Branches
Short ciliary nerves→ cornea