Palpebral fissure
opening between the eyelids (slit)
bulbar conjunctiva
mucous membrane that covers the anterior eyeball (on the bulb itself)
limbus
where the conjunctiva meets the cornea
palpebral conjunctiva
mucous membrane that lines the eyelids (on the eye lid)
adnexa
surrounding structure of the eye (not the eye ball)
globe
eyeball
iris
colored part of the eye
lacrimal gland
makes tears sweep across the eye (located lateral and superior to the upper eye lid)
passageway of tears
inferior canaliculus common canaliculus nasolacrimal sac nasolacrimal duct inferior meatus inferior concha
cornea
clear structure the is in the front of the globe
-responsible for the refracting of light (gross)
conjuctiva
layer of epithelial cells straddles globe on either side anteriorly
pupil
hole in which light passes through to the retina
lens
responsible for the refracting of light (fine tune)
ciliary body
muscle that controls stretching of lens according to amoutn of light entering the eye
zonular fibers
connect ciliary body to lens
posterior chamber
behind iris but in front of the zonular fibers
three layers of the globe
schlera-fiborous CT layer-structure
choroid-vascular layer-nutrients waste
retina-rods and cones-visual
optic disc
where all optic fibers from the retina collect
optic nerve
carries nerve impulses from the eye to the brain
canal of schlem
where aqueous humor exits the eye
glaucoma
increased intraocular pressure
-can be caused by obstruction of canal of schlem
macula
highest concentration of your visual receptors
fovea centralis
where there is the most acute vision
ipsilateral side
same side
contralateral side
opposite side
tumor at the pituitary gland could cause
peripheral vision loss
-where the lateral vision crosses over
homonimous hemianopsia
disruption of the optic tract on the left or right side
-causes visual disruption of peripheral in one eye and medial in the other
problems in the occipital portion cause
quadrant shaped or odd shaped parts of vision
-optic nerves fan out and where the brian interprets the information from the light
rods are responsible for
low light vision
cones are responsible for
color vision
which direction does neural impulse travel once it hits the retina?
back to front (hits the back of the retina and moves forward to the ganglion cells)
CN II
optic nerve
- vision
- light perception
CN III
oculomotor
- innervates 4 of the 6 extraocular muscles
- parasympathetic fibers (orbicularis oculii and iris circular fibers)
- elevation of lid
- ciliary body (accomodation)
CN IV
trochlea
-innervates superior oblique muscle
CN VI
abducens
-innervates the lateral rectus muscle
sympathetic fibers innervate
iris and levator palpebrae muscle
- raises eyelid and dialates pupils
- originate in hypothalamus, go down the neck and back up to the eye
important questions to ask when diagnosing eye problems
gradual/sudden? changes in your vision? close/distant? areas you can't see-fixed or moving? flashing lights? double vision (side by side or on top)/blurry?
common eye symptoms
pain, redness, tearing/watering, itching, dryness
scatoma
flashing lights
what is the vital sign of the eye?
visual acuity
OD
right eye (dexter)-not used anymore
OS
left eye (sinister)-not used anymore
OU
both eyes (uterque)-not used anymore
standardized charts used to test visual acuity
Snellen chart
Handheld chart
Reading
Shapes/numbers
emmetropia
normal vision
myopia
near sighted (eyeball is too long)
hyperopia
far sighted (eyeball is too short)
presbyopia
old age vision loss (lens doesn’t change shape as well as it used to, so we lose that fine tuning)
-harder to adjust from long vision to short vision
amblyopia
visual deficit due to poor ocular deficit
astigmatism
cornea or lens does to refract reflect light
correctly
-corneal
-lenticular
“legal”blindness
2200 or worse with correction
amaurosis fugax
fleeting blindness
-usually related to a vascular problem
anterior eye exam includes
- lids and lashes
- nasolacrimal system
3.
what are the functions of the lids and lashes
protection of the eye (light, foreign objects)
moistening of the cornea (w/lacrimal apparatus)
-vision is affected by dry eyes
canthus
angle of the eyelid
-medial, lateral
tarsal plates
CT that give lids their integrity
meibomian glands
sebacous glands that produce fluid that goes onto the eye
- produce antibodies that help fight infections
- superior to eyelashes
zeis glands
sebacous glands that produce fluid
-small gland on either side of the superior eyelash
what are the functions of the nasolacrimal system?
ocular moisture
- protective
- vision
- anti-microbial
conjuntival fornix
superior and inferior
-crease between the globe and the lid of the eye
conjuntivitis
inflammation of the conjuntiva
- most common cause of infectious conjuctivitis is viral
- usually on one side only
- acute
allergic conjuntivitis
differntial
- clear, watery, mucousy drainage
- bilateral
- long term
cobblestoning
enlargement, proliferation of tissue related to chronic inflammation of tissue as an allergic response
bacterial conjuntivitis
drainage of pus
-purulant
chemosis
redenned edemonous conjuntiva
subconjunctival hemorrhage
increase in intrathoracic pressure
- coughing
- vomiting
- ruptures small vessel between schlera and conjuntiva (causes blood to leak in between two layers)
- more common with people on blood thinners and elderly
- recurrent could indicate bleeding issues
pterygium
triangular overgrowth of conjuctival epithelium
- more common in people exposed to bright sun and dust, hot environments
- treatment is not indicated unless they get to big and grow over the pupil
- usually nasal
pinguecula
area of nodular or enlarged CT
benign
-usually lateral side
-treatment is usually not indicated
ectropion
outward turning of the eyelash and sometimes lid
- usually related to age
- requires surgical correction
entropion
inward turning of the lash
- history of infectious processes
- genetic variant
- blephoritis
- can burn lashes off because of corneal irritation
ptosis
drooping of the upper lid
-may be age related or nerve issues
blepharitis
inflammation of the lid
- redness, flaking, crusting
- commonly associated with acne rosacea
- can be infectious
- chronic occurence is beefy red
xanthelasma
skin tags (fibrous and fatty) found around the nasal canthous of the eye
- may be seen in people with elevated triglycerides, but usually it is not specific to the eye)
- no treatment indicated
dacryocystitis
inflammation of the nasolacrimal gland
orbital cellulitis
infection of the bony orbit surrounding the eye
-ocular emergency
periorbital cellulitis
infection of skin and soft tissue surrounding the eye
hordeolum
sty-infection of a gland in the lid
- presents on lid margin
- tender, irritated
- hot compress may drain spontaneously
chalazion
appearance similar to hordeolum but has developed scar tissue
- chronic problem
- scarred down lesion
- surgical correction
what is the normal size of the pupil?
3-5 mm
miosis
pupillary constriction
mydriasis
pupillary dilation
anisocoria
unequal pupil size
- found normally in 20% of people
- benign if <0.5 mm and reaction to light is normal
direct reaction
when you shine a light on the eye, it constricts
consensual reaction
when you shine a light in one eye and the other eye constricts also
pupillary near reaction
pupils contract when you move an object from far to close to try to focus better
accommodation
adjusting depending on what you are looking at
what happens when you look at something far away?
pupil dilates
ciliary muscles relax, which pulls ligaments taught and causes lens to get thinner
what happens when you look at something close up?
pupils contract
ciliary muscle contracts, which relaxes ligaments and makes lens thicker
Tonic (Adie’s) pupil
dilated pupil slow light response poor accommodation (visual blurring) usually not associated with any pathological finding may have deep tendon reflexes
what is the normal size of the pupil?
3-5 mm
Oculomotor paralysis (CN III)
pupil is chronically dilated
deviated eyes
usually only one eye
Argyll Robertson pupil
small irregular pupils
good accommodation
do not react ot light
seen in CNS tertiary syphilis
Horner’s syndrome
interruption of sympathetic fibers to the eye presents with -ptosis -miosis -anhydrosis
anhydrosis
lack of sweating
