Head & Neck Week 3 Flashcards
What bones make up the border of the medial orbital margin?
Anterior - Frontal bone, frontal process of Maxillary
(Lacrimal makes up Posterior of the border)
What bones makes up the Lateral wall of the orbit?
What bones makes up the Medial wall of the orbit?
Lateral - zygomatic and sphenoid (greater wing)
Medial - maxillary, lacrimal, Ethmoid, Sphenoid
Go to your skull and identify the anterior and posterior ethmoid foramen and the zygomatico-orbital foramen from the orbit.
Says your past self
What is the function and innervation of the orbicularis oculi?
Close eyelids.
CN VII
What muscle in the eye is under sympathetic control?
The Superior Tarsal m., which is a portion of the Levator palpebrae superioris
What is the function and innervation of the Levator Palpebrae m.?
Opens upper eyelid
CN III
What CN keeps the eye open?
Closes eye?
III opens
VII closes
What is the connective tissue skeleton of the eyelid?
Tarsal Plate
What do tarsal glands secrete?
Fatty subst. prevents eyelids from sticking together.
What are the sebaceous glands of the eyelid?
Ciliary glands
What is the mucous membrane of the eyelid and eyeball called?
Conjunctiva
What are two types of Conjunctiva?
Palpebral (continuous with skin)
Bulbar (continuous with cornea and is transparent)
What is the general sensory innervation for the upper eyelid/lower eyelid?
V1
V2
Blood supply upper eyelid:
Lower eyelid:
Branches of Opthalmic
Maxillary and maybe facial angular a.
Trace a tear from eye to nose:
Lacrimal gland > puncta (superior or inferior) > lacrimal canal > lacrimal sac > nasolacrimal duct > Inferior meatus of the nasal cavity
The optic nerve dura is continuous with what in the eye?
The sclera
The cornea is continuous with…
The sclera
What lies between the sclera and the retina?
The Choroid
What is the inner posterior layer of the eye?
The Retina
What is the termination of the choroid that connects with the iris?
Ciliary body
What produces aqueous humor?
Ciliary process
folds in the ciliary body
What separates the anterior and posterior chambers of the eye?
The Iris
What 2 mm. control the diameter of the pupil?
Sphincter pupillae (parasympathetic, CNIII) Dilator pupillae (sympathetic)
T/F
The lens is transparent and vascular.
False.
Lens transparent and avascular
T/F
The anterior and posterior chambers are separated by the Lens.
False.
Iris separates chambers.
What function of what nerve controls the ciliary mm.?
Parasympathetic
CN III
What effect does contraction of the ciliary mm. have on the Lens?
Rounds lens
What effect does relaxation of the ciliary mm. have on the Lens?
Flatten lens
What is the Macula Lutea, what does it contain, and why is it significant?
disc on retina
Fovea centralis
most acute vision.
What is the optic disc?
Where optic n. enters eye.
What are the 2 mm. in the eye that aren’t innervated by CN III?
Superior oblique (CN IV - trochlear) Lateral rectus (CN VI - abducens)
What is the CTR?
Common Tendinous Ring
convergence of most eye muscles near optic canal
What muscles:
Adduct (elevate)?
Adduct?
Abduct?
Superior rectus
Medial rectus and Inferior Rectus
Lateral rectus
(all CN III)
What is the origin, innervation, and function of the Superior Oblique m.?
CTR (then trochlea to superior orbit)
CN IV
Lowers and Abducts (down and out)
The trochlea is medial/lateral to the eye?
Medial
What is the function and innervation of the Levator palpebrae superioris?
Opens eyelid (superior tarsal m.) CN III
(runs over the superior rectus to the eyelid)
Origin, function, innervation of the Inferior Oblique.
Maxillary bone
Elevate and Abducts (up and out)
CN III
What is the function of the Inferior rectus?
Lowers (adducts)
Trace the Motor innervation of CN III to the eye mm. to the point of division:
Occulomotor complex > cavernous sinus > superior orbital fissure > Superior and Inferior divisions
The Superior division of the Occulomotor CN III pathway innervate what mm.?
Superior rectus
Levator palpebrae superioris
The Inferior division of the Occulomotor CN III pathway innervate what mm.?
Medial rectus
Inferior rectus
Inferior oblique
What nuclei do CN IV and CN VI use?
Trochlear nucleus
Abducens nucleus
What are the 4 Ciliary aa. and what do they branch from?
Long posterior ciliary aa.
Short posterior ciliary aa.
Central a. of the Retina
(branch from Ciliary aa. division of opthalmic)
Anterior ciliary aa.
(branch from Lacrimal a. of opthalmic)
see slide 15 eye and orbit
The superior opthalmic and inferior opthalmic vv. anastomose with?
The facial v.
What supplies special sensory and general sensory innervation to the orbit?
Special - II
General - V
(mainly opthalmic division V1, but some maxillary division V2)
L
F
N
What are the nasociliary divisions?
Long ciliary nn. (eyeball)
Posterior ethmoidal n. (sphenoid sinus, ethmoid air cells and nasal cavity)
Ant. Ethmoid n. > External nasal branches
Infratrochlear n.
What do the Long Ciliary nn. innervate?
Eyeball
What does the Infratrochlear n. innervate?
Medial upper eyelid and lacrimal sac.
What innervates the Special Sensory and General Sensory functions in the orbit?
Special - optic nerve CN II via optic canal
General - Mostly V1 (some maxillary division of V2)
What innervates the lower eyelid / eyeball?
Inferior palpebral n.
V2
Oculomotor Parasympathetic mm. and ganglion?
mm. - ciliary m. and sphincter pupillae
ganglion - ciliary
What is the parasympathetic nucleus of III?
Edinger Westphal nucleus
What post-ganglionic fibers innervate the ciliary mm. and the constrictor pupillae mm.?
Short ciliary nn.
What is the nucleus, ganglion, and target for VII’s parasympathetic function?
Superior Salivatory nucleus
Pterygopalatine ganglion
Lacrimal gland
What nn.’s does VII’s parasympathetic function ride on from the pterygopalatine fossa to the lacrimal gland?
Zygomatic V2
Lacrimal V1
Pathway Parasympathetic to Lacrimal (VII)
Superior Salivatory nucleus > internal acoustic meatus > facial canal > greater petrosal > joins deep petrosal at pterygoid canal > pterygopalatine fossa > V2 zygomatic > V1 lacrimal > lacrimal gland
Does VII’s parasympathetic pathway to the lacrimal pass through the infratemporal fossa?
NO
greater petrosal goes right to the PPF via pterygoid canal
What 2 muscles of the eye need Sympathetic innervation?
Dilator pupillae
Superior tarsal muscle
Sympathetic pathway to the eye.
T1-L2 > superior cervical ganglia (synapse) > post-ganglionic fibers hitchhike on IC to opthalmic > long ciliary nn. or muscular branches of III to dilator pupillae and superior tarsal muscle
What cranial nn. does the Corneal Reflex involve, and what function do they perform?
V - sensory component
VII - motor component
Corneal reflex:
Absent ipsilateral with normal contralateral response
V - normal
VII - abnormal ipsilateral