Optic Disc
Cup:disc ratio
1:3
physiologic cup
A small whitish depression in the optic disc, entry point for retinal vessels
Eye examination
A. Visual Acuity B. Gross inspection C. Color vision D. EOMs E. Position & Alignment F. Visual Fields G. Funduscopic exam what are these components of?
more visible
Are disc vessels more or less visible with papilledema?
open angled
Chronic glaucoma or _______ is when the canal is blocked by microdeposits; most common
x chromosome
Defective color vision is hereditary, a recessive gene carried on ______
optic atrophy
Disc appears white, vessels are absent
pale
In Glaucomatous Cupping, the base of the enlarged cup is _____
diabetes
In ____ may see dilated veins, exudates, hemorrhages, neovascularization (fine networks of new blood vessels)
chronic hypertension; acute severe hypertension
In ____ may see: A-V nicking, "copper wiring", "silver wiring"; In _____ may see arteriolar narrowing, hemorrhages, exudates, even papilledema
Lacrimal apparatus
Inspect & palpate region of lacrimal gland and lower orbital rim for nodules, discharge. Look for ↑ tearing or lack of drainage
glaucoma
May see ↑ cup size in _____
same
Most important is that the cup be the ____ in both eyes.
increased intraocular pressure -- glaucoma
Result of blocking the canal of schlemm
refractive; non-refractive problem
Testing vision using both snellen and rosenbaum may be helpful in determining whether decreased vision is a ____ or _____ problem
color of disc
You observe these where? pink-white - normal White - can see with optic atrophy Angry looking with dilated, tortuous vessels -- papilledema
rings and crescents
___ and ___ are often seen around the optic disc; not part of the disc
Grayish
___ spots are often seen at the base of the cup
Arcus senilis
a narrow opaque band encircling the cornea, common in old age
presbyopia
aging vision or difficulty to see close
Strabismus
an abnormal turning of either eye inward (crossed eyes; esotropia) or outward (wall-eyes; exotropia).
optic disc
appears yellowish/orange to creamy pink with tiny vessels
Non-paralytic Strabismus
caused by imbalance in muscle tone, seen more commonly in kids, constant in all fields of gaze. "Cover-uncover" test may be helpful.
paralytic strabismus
caused by paralysis of 1 or more extraocular muscles, defect will be more or less severe depending on direction of gaze
bulbar conjunctiva
clear mucous membrane that covers most of the anterior eyeball
presbyopia
commonly arises & progresses from age 40-60; also manifests as "farsightedness"; accommodation (thickening of lens) is needed for near vision; with age the lens becomes stiffer and doesn't thicken as readily
optic atrophy
death of optic nerve fibers leads to loss of the tiny disc vessels
myopia
develops as eye grows, often seen in children/young adults; may need glasses to see distant
Ptosis
drooping of eyelids (defect in CN3)
Ishihara
example of a color chart
cataracts
example of a non-refractive problem
hyperopia
farsightedness- difficulty to see close
cataracts or macular degeneration
gradual onset of bilateral visual loss
pink; hyperemic; margins blurred; visible
in papilledema, optic disc is ___ or _____ the disc is swollen with ______; physiologic cup is not _____
Glaucomatous Cupping
increased pressure within the eye, leading to increase cupping or backward depression of the disc and atrophy
medullated nerve fibers
irregular white patches with featured margins, obscure the disc edge and retinal vessels; uncommon; no pathological significance
fovea
lateral and slightly inferior to the disc; darkened circular area
myopia
nearsightedness- difficulty to see far
aqueous humor
produced by ciliary body → posterior chamber → anterior chamber→ canal of Schlemm- this describes the flow of what?
acute (narrow) (open angled)
rare eye disease; canal is blocked by the iris which is position at and abnormal angle
blepharitis
reddish and scaling in eyelids
developmental; sclera
rings and crescents are ___ variations that appear as either white ___ or black retinal pigment, or both. (usually temporal side of the disc)
optic atrophy
seen in optic neuritis, MS, and temporal arteritis
fundus
structures on this included the retina, choroid, fovea, macula, optic disc, and retinal vessels
macula
surrounds the fovea; no discernible margins
papilledema
swelling of the optic disc; elevated intracranial pressure causes intraaxonal edema along the optic disc
Snellen Test
tests distance vision; testing is done at 20 ft.
Rosenbaum
tests near vision; at 14 in. is "equivalent" to Snellen
larger
the _____ the second number in vision scores, the worse the vision
less than half
the cup is normally ____ of the disc
open angled and narrow
two types of glaucoma
patient could read the 40 line with glasses
what does 20/40 corrected mean?
at 20 ft a pt can read print that a person with normal vision could see at 200 ft
what does vision at 20/200 mean?
vision in the better eye is 20/200 (corrected) or less
when is a person considered legally blind?
temporal hemianopsia
when the patient repeatedly doesn't see your fingers until they have crossed the line of gaze
centrally or toward temporal side of the disc
where is the cup located on the optic disc?
optic disc
where is the physiologic cup?