Eye Flashcards
V1
supraorbital
supratrochlear
infratrochlear
lacrimal
V2
infraorbital
Lacrimal gland is ____ and _____ to the eye!!!!
superior; lacrimal
Flow of aqueous humor and travels out of ?
Canal of schlemm
Tunics : superficial to deep?
Fibrous>vascular–>neural
Fibrous layer includes
sclera and cornea
Vascular layer includes
choroid, ciliary body, suspensary ligaments, iris
Neural layer includes
Retina (pigmented part, neural part, has rodes and cones)
Mydriasis
dilation of the eye, term is usually used to describe abnormal dilation (drugs or disease)
Emmetropia
normal vision
Ametropias (ocular disorder)
myopia, hyperopia, astigmatism, prebyopia
Retina has two parts?
Pigmented Part
Neural Part
Pigmented part of retina
Thin outer layer
Absorbs light preventing ‘visual echoes’
Neural part of retina
Thick inner layer
Contains photoreceptors, neurons, and supporting cells
Two types of photoreceptors?
Cones and Rods
Rods
Function in dim light
Don’t provide sharp vision or color vision
Periphery of retina
125 million
Cones
Operate best in bright light Provide high acuity Color vision Center of retina 6 million
Organization of cones and rodes
horizontal cells
Organization of bipolar cells
Amacrine cells
Organization of ganglion cells
Become optic nerve
Retinal regions
Macula lutea
Fovea centralis
Optic Disc (papilla)
Macula lutea
Lateral to optic disc
Contains mostly cones
Fovea centralis
Contains only cones
Maximal visual acuity
Optic Disc
Blind spot, contains no rods or cones
Unmyelinated axons (become myelinated after the optic disc)
Central artery and vein enter/exit eye
What makes a person colorblind?
Not having all the different types of opsin (red, blue, green cones). These cones may be nonfunctional, absent, unable to manufacture pigments
Visual Pathway just cell?
Long version?
Photoreceptor—>bipolar cell–>ganglion cell (unmyelinated axons)–>visual cortex of cerebral hemispheres (occipital lobe)
Photreceptorganglion cellsoptics discoptic nerveoptic chiasmOptic tract–>geniculate mucleus of thalamusvisual cortex of opposite occipital lobe
Lesion of optic nerve causes
blindness
Lesions of optic chiasm causes
Bitemporal hemianopsia (partial blindness)
Lesions of optic tract
Homonymous hemianopsia
loss of half of the field of view on the same side in both eyes
Eye Mnemonic
(LR6SO4)3
Lateral Rectus, VI
Superior Oblique, IV
All others, III
strabismus
cross-eyed
Lack of coordination of the extraocular muscles
periorbital fascia
Periosteum of the orbit
Also called periorbita
Fat surrounding the eye
Central retinal artery travel with the ___ and supplies ___.
optic nerve; retina
2 nodes responsible for lymphatic drainage of the orbit?
preauricular node
submandibular node
bones creating the orbital margin?
zygomatic bone
maxilla
frontal bone
superior wall of orbit
Frontal
Lesser wing of sphenoid
Inferior wall of orbit
Maxilla
Zygomatic
Palatine
Medial wall of orbit
Ethmoid
Lacrimal
Frontal
Maxilla
Lateral wall of orbit
Zygomatic
Greater wing of the sphenoid
Frontal
Inferior rectus innervation
CNIII
medial rectus innervation
CN III
Lateral rectus Innervation
CN VI
Superior oblique innervation
Trochlear nerve IV
Inferior oblique innervation
CNIII
The inability of the lens to change shape due to changes associated with old age is referred to as:
Presbyopia
Which of the following is a component of the optic disc or papilla?
central artery
The ophthalmic artery is a branch of the
internal carotid artery
The left optic tract contains:
Fibers from the temporal half of the left eye and nasal half of the right eye
Identify the branch of the ophthalmic artery that pierces the optic nerve.
Central artery of the retina
Infraorbital a. is a branch of
external carotid artery
If your vision is 20/15, this means that you can
Better than normal! See objects at 20 feet that individuals with normal eyesight can see at 15 feet.
20-how far you see
15-how far your standing, what your expected to see
e.g. 20/200-nearsighted and legally blind- at 20 ft away you see what normal ppl see at 200 ft
What muscle medially rotates (intorts), depresses and abducts the eyeball to facilitate downward and outward visual gaze orientation?
Superior oblique
What artery supplies the sclera?
Long ciliary artery
Common tendinous ring includes
CN 2, 3, 6
V1
Opthalmic artery
Layer of eye that is directly deep to the sclera
choroid
Optic canal includes
opthalmic artery
optic nerve
Which skull foramina does the opthalmic artery traverse to enter the orbit?
optic canal
The space between iris and ciliary body and the lends is the
posterior chamber
Anterior cavity is divided by the
iris
Which one adducts, depresses and laterally rotates?
Inferior rectus
Strombismus toward medial
Lateral rectus
ptosis due to what muscle?
droopy eyelid due to Levator palpabrae superioris (resp. for opening eyelid)
pathway of tears
Lacrimal gland–>puncta–>sup. and inf. lacrimal canaliculi–>lacrimal sac–>nasolacrimal duct
Myopia
Nearsightedness
Image is focused anterior to retina
Hyperopia
Farsightedness
Image is focused posterior to retina
Astigmatism
Nonspherical eye
Parts of image focus at multiple points
Presbyopia
Loss of elasticity in lens
Age-related, 40-50
“reading glasses”
Ex. of farsightedness aka hyperopia
There is a ____ difference between the axis of the orbit versus the axis of the eye.
23 degrees
Function of superior rectus
Elevation, adduction, medial rotation of eyeball
Inferior rectus function
Depression, adduction, lateral rotation of eye
Medial rectus function
adduction of eyeball
Lateral rectus function
Abduction of eyeball
Superior oblique function
Depression, abduction, medial rotation of eyeball
Inferior oblique function
Elevation, abduction, lateral rotation of eyeball
Damage to abducens nerve would result in inability to perform what action?
rotate eye laterally
Obliquus superior muscle is innervated by
CN 4
Contents of SOF
CN 3,4, 6, V1, superior opthalmic vein, sympathetic fibers from cavernous plexus.
Superior tarsal (Muller’s) muscle
Elevates eyelid
Smooth muscle
Sympathetic control, T1, via superior cervical ganglion
ptosis
Orbicularis oculi
closes eyelid
CN VII
Levator palpabrae superioris
Opens upper eyelid
CN III
Aqueous humor made by ___ drains into ___.
Ciliary body; superior opthalmic vein