Intro to Eye Flashcards
what are the corners of the eyes where the upper and lower lid join
inner and outer canthus (outer obvi lateral)
bulbar conjuctiva
covers anterior sclera and ends at the cornea
palpebral conjuctiva
lines the inside surface of the eyelids
2 types of sebaceous glands–> differentiate
gives the oil layer
1) Meibomian glands –>BIG sebaceous glands at the INNER eyelid margins (most of lubricant)
2) gland of Zeis–> TINY at the outer eyelid margins in the hair follicles
describe lacrimal apparatus
lacrimal gland–> superior and inferior lacrimal punctum–> lacrimal sac–> nasolacrimal duct –> inferior meatus and turbinate
outer layer of eye
cornea and sclera
aka fibrous layer
middle layer of eye
vascular tunic
has uvea or uveal tract–> ciliary body, iris, choroid (ICC)
inner layer of the eye
sensory tunic
retina (rods, cones, optic disc, macula, fovea)
describe chamber separation
cornea to iris–> anterior chamber
iris to lens–> posterior chamber
everything behind the lens –> vitreous body!!
describe the fluids in each chamber
1) anterior and posterior chamber= aqueous humor
2) vitreous body= vitreous fluid which is shock absorbing, so jelly like substance
describe the whole optic nerve thingy
optic nerve –> optic chiasm–> optic tract
what is the gold standard for measuring IOP
Goldmann’s applanation
- numbing drops, the put device on the surface of the eye and it measures the amount of force needed to flatten a given area of the cornea
- if you have higher pressure, harder to flatten cornea
- blue light helps fluoresce
- we want the two semicircles to be connected
- if high pressure–> far apart & if low pressure, overlapping a lot
tonopens
handheld device, CONTACT!
TAP the eye and take average–> doing it multiple times
using numbing
tonometer
this is the machine where it puffs air into your eyes
more for a screening
**measures IOP and it is NON-contact
perimetry
formal visual field testing
put face into machine and there are flashing lights and you map it out
shadings mean that loss of vision or unable to pick up the signal
what is fluorescein staining used for
solution that helps us detect abrasions and foreign bodies (commonly used in ER)
-solution, single strips, or IV sol for angiography
1) number
2) pace strip on lower eye lid and tears will usually distribute the stain all over
3) use blue light to see the defects
when are gram stains and cultures considered
newborns
immunocompromised
patients that do not respond to tx
fluorescein angiography
(diagnostic evalv)
IV fluorescein dye can be seen in the RETINAL VESSELS using a camera
*****SENSITIVE way to look at changes w diabetic retinopathy or macular degeneration
topography
gives a map of the cornea
used for tx of refractive errors (lasik) and other issues w cornea, cataract surgery
what is the screening test for assessing the macula
1) grid; hold it 14 inches away–> ONE EYE at a time
2) focus on center; if pucker shape w wavy lines or missing grid parts–> vascular changes associated w wet macular degeneration
ishihara plates
used for color testing
daylight 30 inches away
10 or More ready correctly = normal
≤7 read correctly, color deficient
everyone can read 12?
hyperopia
farsightedness
shorter than normal eye–> light rays focus behind the eye
need biconvex lens to converge the light rays more
myopia
near sightedness
longer than normal eye; light rays focusing in FRONT of eye
need biconvex lens to converge the light rays more
astigmatism
difference in refractive power along any main refractive services (cornea, anterior lens posterior lens)
need a SPECIAL LENS to correct the defect