Flashcards in Orbit & Eye Deck (113):
what are the 4 features of the eyelid
where is the palpebral conjuctiva
membrane lining inner eyelid
where is the bulbar conjuctiva
membrane lining surface of eye
where is the conjuctival sac
potential space between these membranes
where is the fornices
conjuctival reflections from eyelid to eye
what provides form for eyelids?
superior and inferior tarsus
what sebaceous glands are seen through conjuctiva
what tendon does CN III innervate
levator palperae superioris muscle
what are the bones of the orbit
what arteries go through the anterior and posterior ethmoidal foramen
anterior and posterior ethmoidal arteries
Objects piercing roof enter ___
anterior cranial fossa
Objects piercing floor enter ?
Objects piercing medial wall enter ?
ethmoid air cells
Objects piercing lateral wall enter ?
Objects piercing superior orbital fissure enter ?
middle cranial fossa
what is the floor of the orbit?
roof of maxillary sinus
what does a medial orbital wall injury affect?
ethmoidal air cells
what does a lateral orbital wall injury affect?
what goes through the optic canal
CN II and opthalamic artery
what goes through the superior orbital fissure?
CN III, IV, V1, VI, and opthalamic vv
what goes through the supraorbital notch/foramen
supraorbital n (CN V1) & a
what goes through the inferior orbital fissure?
infraorbital and zygomatic n (CN V2) and a
what goes through the infraorbital foramen
infraorbital n (CN V2) and a
what goes through the anterior ethmoidal foramen?
anterior ethmoidal n and a (CNv1)
what goes through the posterior ethmoidal foramen?
posterior ethmoidal n (CNv1) and a
what goes through the foramen rotundum
what are the features of the external eye
mucous membrane of eye and lids
posterior 5/6 of outer layer (white part)
anterior 1/6 of outer layer (transparent)
what are the 4 features of the middle eye
thin middle layer of ciliary aa & vorticose vv
define cilary body
smooth muscle around lens for accommodation
what controls focal point of lens?
colored smooth muscle behind cornea controlling pupil size
adjustable aperture through which light enters eye
how does the ciliary body muscles affect the zonular fibers?
change the tension of the zonular fibers, change the focus of the lens
what are the 4 features of the internal eye
neural layer of eye which receives a light rays
define macula lutea
oval region of retina for visual acuity
defina fovea centralis
most acute vision site at center of macula
define optic disc
regions where CN II and retinal vessels enter/exit
what represents a blind spot?
optic disc (no photo receptors)
why is the optic disc considered a blind spot?
T/F vessels are over the fovea centralis
how do the meningeal layers extend to the eye?
through the optic nerve
what are the 4 features of the refractive media of the eye
largely responsible for refraction of light in the eye
focuses light rays & near or distant objects on retina
define aqueous humor
watery filling anterior to lens
define vitreous humor (body)
gelatinous filling posterior to lens
what is the nervous "visual" layer
what are the 4 features of the lacrimal apparatus
whats is lacrimal gland function?
produces lacrimal fluid (tears), flows inferomedially
what is the lacrimal canaliculi function
transports tears to lacrimal sac
what is lacrimal sac function
drains tears to nasolacrimal duct
what is nasolacrimal duct
drains tears through nasolacrimal canal (under inferior nasal concha)
levator palpebrae superioris m action?
raises upper eyelid
superior rectus m action?
elevates and adducts eye
rotates eye medially
inferior rectus m action?
depresses and adducts eye
rotates eye laterally
lateral rectus m action?
medial rectus m action?
superior oblique m action
depresses and abducts eye
inferior oblique m action?
elevates and abducts eye
which muscle helps the eye look "down and out"
superior oblique m
what tendon is oriented with superior oblique m?
which muscle makes the eye look up and out?
inferior oblique m
which muscles ABDUCT the eye?
which muscles ADDUCT the eye?
which cranial nerve supplies superior oblique m
which muscles does the CN III supply?
which cranial nerve supplies lateral rectus m?
which cranial nerve carries p-symp to ciliary ganglion?
how can the eye be placed to test lateral and medial rectus mm?
how can the eye be placed to test superior and inferior rectus mm?
how can the eye be placed to test superior and inferior oblique mm?
the position of ab/adduction is ____ of muscle action
what is the optic nerve sensory for?
special sense of sight
where are the optic nerve fibers?
between the eye and chiasm
what is the optic chiasm
intermingling of nerve fibers
what is the optic tract
nerve fibers from chiasm to brain
what are the two visual fields of the optic pathway
which visual field crosses over the chiasm?
which visual field remains ipsilateral?
what does visual field testing detect?
what does the optic nerve lesion result in?
total blindness in affected eye
what does the optic chiasm lesion produce?
loss of peripheral vision
what does the optic tract lesion result in?
ipsilateral nasal visual field loss and contralateral temporal field loss
pattern of optic tract lesion is due to ____ of ____ visual fields
crossing of temporal visual fields
what does the ciliary ganglion receive?
p-symp from CN III
what does the ciliary ganglion supply?
p-symps to ciliary muscle and pupillary sphincter muscle
what does pupillary dilator muscle receive?
sympathetics from internal carotid plexus
where are the preganglionic sympathetic cell bodies?
what does the pupillary light reflex test?
CN II and CN III
how do we tell if there is a CN III p-symp lesion?
pupil remains dilated
what are the 3 divisions of the CN V1
what does the nasociliary n contain?
ethmoidal and infratrochlear nn
long ciliary nn (sensory and symp) to posterior eye
what does the frontal n branch to?
supraorbital and supratrochlear nn
what does the lacrimal n supply?
lacrimal gland and conjuctiva
what are the 7 arteries of the orbit and eye
posterior ciliary aa
central retinal a
what does the ophthalmic a give rise to?
all arteries of the eye
what does the posterior ciliary aa supply?
outer and middle layers of the eye
what does the central retinal a supply?
inner layer of retina
what does the ethmoidal a supply
anterior cranial fossa, nose, and sinuses
what does the supraorbital a supply
central region of forehead
what does the supratrochlear a supply
medial region of forehead
what does lacrimal a supply
what are the 4 veins of the orbit and eye
superior ophthalmic v
inferior ophthalmic v
central retinal v
what does the vorticose vv drain into?
superior and inferior opthalmic vv
where does central retina v drain?
what does the inferior ophthalmic v anastomose with and drain to?
anastomose with facial v and drain to cavernous sinus
what layer does the vorticose veins drain?