Eyes And Orbit Flashcards
Nerves of the orbit
Supraorbital nerve (V1)
Optic nerve
Oculomotor
Trochlear
Abducent
maxillary (V2)
Canals of the orbit
Supraorbital foramen
Optic canal
Superior orbital fissure
Inferior orbital fissure
Infraorbital foramen
Oculomotor nerve (CN 3)
Parasympathetics:
- pre synaptic: synapse on ciliary ganglion
- post synaptic use short ciliary branches of V1 to get to the eye
- muscles that get parasympathetics are the sphincter papillae and ciliary Muscles*
Motor: most extraocular eye muscles
- levator palpebrae superioris
- superior rectus
- medial rectus
- inferior rectus
- inferior oblique
Trochlear nerve (CN 4)
Motor to the superior oblique muscle
Abducent nerve (CN 6)
Motor to the lateral rectus muscle in the eye
frontal branch of the Ophthalmic nerve (V1)
Supraorbital and supratrochlear nerves used for sensory of the skin of the forehead
Bones of the orbit
Frontal
Maxillary
Zygomatic
Lacrimal
Sphenoid
Palatine
Ethmoid
Three openings of the orbit
Optic canal
- optical nerve and ophthalmic artery
Superior orbital fissure
- CN 3,4,V1,6 and the superior/inferior ophthalmic veins
Inferior orbital fissure
-V2 and the infraorbital artery
Lacrimal branch of the Ophthalmic nerve (V1)
Take some parasympathetics from V2
Also carry sensory to lacrimal glands and the tarsal plates (upper eyelids)
Nasocillary branch of the Ophthalmic nerve (V1)
3 main branches
Long ciliary: sympathetic and somatic sensory of the eye itself
Short ciliary: sympathetic, somatic sensory, and parasympathetic from ciliary ganglion to the eye itself
Ethmoid branches: parasympathetics from facial nerve (CN7) and somatic sensory to the nasal cavity, sphenoid sinus and ethmoid air cells
Maxillary nerve (V2)
Carry postsynaptic Parasympathetic innervation from facial nerve (CN7) to the lacrimal gland
Muscles in the common tendinous ring
Superior rectus (CN3)
Inferior rectus (CN3)
Medial rectus (CN 3)
Lateral rectus (CN 6)
Superior oblique (CN 4)
Superior rectus
Innervated by oculomotor (CN3)
Attachment at top of eye and is primary elevator
- also some adduction and medial rotation
Inferior rectus
Innervated by oculomotor (CN3)
Attachment to the bottom of the eye and is the primary depressor of the eye
- also does adduction and lateral rotation
Medial rectus
Innervated by oculomotor (CN3)
Attachment is to the medial aspect of the eye
Conducts eye adduction