Eye Exam Flashcards
External Eye components
eyelid, conjunctiva, lacrimal gland, eye muscles, bony orbit
What gland provides oils to the tear film?
Meibomian glands
The conjunctiva is divided into two parts?
Palpebral conjunctiva - covers the inside of the eyelid
Bulbar conjunctiva - covers anterior surface of the eye (except cornea and eyelid in contact with the globe)
What gland produces tears?
Lacrimal gland
What muscles are controlled by the oculomotor n. (CN III)?
Levator Palpebrae Superioris, Superior Inferior and Medial Rectus, and Inferior Oblique m.
What extraocular muscles are controlled by abducens (CN VI)?
Lateral Rectus m.
What extraocular muscles are controlled by trochlear n. (CN IV)?
Superior Oblique m.
Internal Eye components
Sclera, cornea, uvea, choroid, ciliary body, iris, retina
Dense, AVASCULAR, the “white” of the eye, physically supports the eye
Sclera
The anterior 6th of the globe continuous with the sclera, clear, RICH INNERVATION, AVASCULAR
Cornea
Composed of choroid, ciliary body, iris
Uvea
circular, contractile muscular disc containing pigment cells, controls the aperture of the pupil
Iris
produces the aqueous humor and contains the muscles controlling accommodation
Ciliary body
pigmented, richly vascular layer that supplies oxygen to the outer layer of the retina
Choroid
biconvex, transparent structure located immediately behind the iris. Highly elastic and contraction/relaxation of the ciliary body changes its thickness (depending on distance)
Lens
Sensory network of eye, transforms light to electrical impulses
Retina
Point on retina where vessels and nerves converge, creating a blind spot
Optic disc
Point of greatest visual acuity
Macula densa
What weeks do eyes develop?
8 weeks
Term infants are hyperopic, which means…?
visual acuity less than 20/400
Peripheral visions develops….
by birth
Central vision is developed by…
3-4 months
Adult acuity is achieved by….
4 years old
Eye changes when pregnant
hypersensitivity, refractory power changes, greasy sensation or blurred vision for contact wearers, spontaneous subconjunctival hemorrhages due to decreased intraocular pressure
Presbyopia occurs in older adults, meaning….
progressive weakening of accommodation (ability to focus)
What age does the lens become more rigid and ciliary muscles weaken?
45 years
Lens fibers become denser centrally as we age, known as…
cataract formation (clouding of the lens that can become partially or totally opaque
Risk Factors for cataracts
steroid use, UV light, cigarette smoke, diabetes, aging
Diplopia
seeing double images, not blurred vision
Older adults eyes
decrease in central vision, excessive tearing, dry eyes, scleral brown spots, eye pain at night
Pregnant women eyes
pregnancy-induced hypertension PIH or gestational diabetes; diplopia, scrotomata, blurred vision, amaurosis
How far away must a patient stand from the snellen chart
20 ft
legally blind
20/200
20/20 means
the patient can read at 20 feet what the normal person can read at 20 feet; smaller fraction - worse vision
Confrontation test
Tests peripheral vision; only suggest abnormalities
What do eyebrows tell you about thyroid function?
coarse, short may be hypothyroidism
xanthelasma
elevated plaque of cholesterol deposited in macrophages (medial portion of eye)
eyelids sign for hyperthyroidism
twitching of eyelids
ptosis
drooping of an eyelid (congenital or acquired weakness) CNIII
ectropion
lower lid is turned away from the eye exposing the inside of the lower lid
entropion
lower lid turned in to eye and eyelashes cause irritation
Hordeolum
acute suppurative inflammation of the follicle of an eyelash can cause a red or yellow lump
crusting along the eyelashes
blepharitis by bacterial infection, seborrhea, psoriasis, rosacea, or allergies
lagophthalmos
eyelids that do not completely close to cover the eyes
subconjunctiva hemorrhage
bright red bloody spot next to healthy conjunctiva
pterygium
abnormal growth of conjunctiva over the cornea from the limbus
arcus senilis
lipid deposits in the periphery of the cornea, common after age 60, indicates lipid dysfunction before 40
miosis
constricted pupils bilaterally <2mm, drug-related
mydriasis
pupillary dilation bilaterally >6mm, with coma
iridocyclitis
failure to constrict with light stimulus
anisocoria
noticeable differences in pupil size
iritis constrictive response
uveitis, pupil constriction and reddened eye
oculomotor damage
pupil dilated and fixed in the lateral downward
adie pupil
dilated or slowly responsive pupil due to impairment of parasympathetics
senile hyaline plaque
dark, slate gray pigment just anterior to the medial rectus attachment
nystagmus
involuntary rhythmic movement of the eye
strabismus
esotropic: inward drifting of eye
exotropic: outward drifting of eye
both eyes cannot focus on 1 object simultaneously, but can focus separately
drusen bodies
small discete spots more yellow
myelinated retinal nerve fibers
optic disc is ill-defined and obscured vessels
papilledema
loss of definition of the optic disc, due to increased intracranial pressure
glaucomatous optic nerve head
“cupping” of the optic disc disappearnce of blood vessels,
episleritis
inflammation of the superficial layers of the sclera anterior to the insertion of the rectus muscles
band keratopathy
deposition of calcium in the superficial cornea
corneal ulcer
disruption of the corneal epithelium or stroma
horner’s syndrome
interruption of sympathetic supply to the eye, miosis, ptosis and hemiandriosis
cataracts
opacity in lens
diabetic retinopathy (background)
dot hemorrhages or microaneurysms
diabetic retinopathy (proliferative)
new blood vessels, floaters, blurred vision, progressive visual acuity loss
lipemia retinalis
serum tryiglycerides >2000, salmon-pink vessels to whitish
glaucoma
nerve cells die producing a characteristic look to the optic nerve, peripheral vision loss, halos, pain
retinal hemorrhages in infancy
bilateral hemorrhaging
