Eye, Nose & Ear Flashcards
What are the 7 orbit bones?
Frontal Sphenoid Ethmoid Palatine Lacrimal Maxilla Zygomatic
*medial wall faces forward but lateral wall face laterally
Openings of Orbit: name bone and nerve
- Supraorbital foramen/notch:
Frontal bone; Supraorbital nerve: V1 terminal branch
Openings of Orbit: name bone and nerve
2. Optic Canal:
Sphenoid bone; Optic nerve and ophthalmic artery
Openings of Orbit: name bone and nerve
3. Superior orbital fissure:
Sphenoid bone; CN V1, ophthalmic division
-CN III, IV, and VI: blood vessels
Openings of Orbit: name bone and nerve
- Ethomodial foramina:
-Ethmoid bone; ethmoidal nerves and arteries (nasociliary, V1 branches)
Openings of Orbit: name bone and nerve
- Nasolacrimal canal: lacrimal bone and maxilla
Lacrimal bone and maxilla
-nasolacrimal duct: drainage of tear
Openings of Orbit: name bone and nerve
Inferior orbital fissure
sphenoid and maxilla
-venous plexus
What is the function of the lacrymal apparatus?
Tear production:
- moisture in the eye
- emotional expression
Drainage of tear:
- tear flows inferomedial across the eye to lacrimal canaliculi
- lacrimal canacliculi into the nasolacrimal duct (opening in the inferior meatus of nose)
What is the shuttle nerve for visceral motor innervation of the lachrymal apparatus:
CN V: Trigeminal N. as the shuttle
What is the sympathetic and parasympathetic visceral motor innervation of the lachrymal apparatus:
Sympathetic: postganglionic axons from the superior cervical ganglion to form deep petrosal nerve
-postganglionic fibers hike zygomatic nerve (V2) to lacrimal (V1)
Parasympathetic: preganglionic axons from CN VII: facial n. to from greater petrosal nerve
- *cross pterygoid canal: nerve of pterygoid canal**
- preganglionic axons form synapse in the pterygopalatine ganglion
What are the three layers of the orbit wall?
Out layer
- sclera: white dense (most of the eyeball) - cornea: clear dense for light passing through
Choroid: blood vessel plexus
Retina: sensory circulation
These are contents of what structure? anterior and posterior chamber -Iris: pupil -pupillary light reflex -Ciliary body: lens -Vitreous body: humor
Contents in the eyeball
What is the somatosensory innervation for the orbit?
Ophthalmic N. (V1) from CN V
What is the neurovascular orbit supply (medial to lateral for the main branches V1)?
Nasociliary nerve
Frontal nerve: ciliary nerve, supratrochlear and supraorbital nerves
Lacrimal nerve: smallest branch
*NFL
What is the blood supply of the orbit?
Ophthalmic artery from the internal carotid artery
What are the branches of the ophthalmic artery?
Central retinal artery Ciliary artery Supraorbital artery Ethmoidal artery Lacrimal artery
What does the supraorbital artery give blood supply to?
scalp and eye
What is the sympathetic and parasympathetic: visceral motor innervation of the eyeball?
Sympatehtic: postganglionic fibers from superior cervical ganglion. hike long/shhort ciliary nerve
Parasymapthetic: preganglionic fibers from CN III (Oculomotor N.) to for, ciliary ganglion
In the eyeball what does the ciliary body do?
modulate size of lens
What is the innervation of the ciliary body?
Only innervated by the postganglionic fibers from ciliary ganglion (parasympathetic)
What is the sympathtic function of te Iris?
dilate the pupil
What is the parasympatetic funtion of the Iris?
Constrict the pupil-pupillary light relfex
What CN is the afferent (toward) for the Iris?
Afferent; CN II
What CN is efferent (away) for the Iris?
Efferent; CN III
What syndrome is this referring to:
- must be balanced
- Constructed pupil
- eyelid ptosis
- no sweating on affected side
Horner’s Syndrome
What are the structures of the eyelid?
Msucle tendons
Orbital septum
Palperbral ligamnet: Lateral/medial
Tarus plate: superior/inferior
What is the nerve innervation for the eyelid?
V1: opthalamic (superior) and V2: maxillary (inferior) terminal nerve branches
What is the blood supply for the eyelid?
anstomosis of external and internal cartis arery terminal branches
What are the functions of the eyelid?
- Protecting
- Facial expression
What is the function of the orbicularis oculi:
orbital part:
palpebral part:
Close eyelid
wink
blink
What is bell’s palsy?
cant close eye
What is the nerve innervation of Orbicularis oculi:
CN VII (Facial N.)
What is the function of the Levator Palpebrae Superioris?
Open eyelid
What is the muscle attachment of the levator palpebrae superioris? (proximal/distal)
prox: common tendinous ring attcahing posterior orbital wall
distal: upper eyelid
What nerve innervates the levator palpebrae superioris?
What deficit is can be related to this muscle/nerve?
CN III: Oculomotor
Fully ptosis: dangerous triagnle/cavernosus sinus