Unit 4B Vision

Front 1

sclera

Back 1

external layer of eye
opaque tissue making up the whites

Front 2

uvea

Back 2

-middle layer of eye
-heavily pigmented
-consists of choroid, ciliary body, iris

Front 3

iris

Back 3

-colored portion of external eye
-muscles contract & relax to control pupil size

Front 4

retina

Back 4

-innermost layer
-sensory receptors transmit impulses to optic nerve
-contains rods & cones

Front 5

rods

Back 5

-work @ low light levels
-provide peripheral vision

Front 6

cones

Back 6

-active @ bright light levels
-provide color & central vision

Front 7

optic disc

Back 7

-creamy pink to white depressed area in retina
-where optic nerve enters & exits eyeball

Front 8

optic fundus

Back 8

-area inside back of eye that can be seen w/ ophthalmoscope

Front 9

light waves pass through which structures on the way to the retina?

Back 9

-cornea, aqueous humor, lens, vitreous humor

Front 10

how do light waves pass through structures?

Back 10

-each has different density
-causes waves to bend (refract) & focus images on the retina

Front 11

cornea

Back 11

clear layer forming external coat on front of eye

Front 12

aqueous humor

Back 12

clear, watery fluid that fills anterior & posterior chambers of eye

Front 13

lens

Back 13

-circular, convex structure
-lies behind iris & in front of vitreous body
-normally transparent

Front 14

vitreous body

Back 14

-clear, thick gel
-fills vitreous chamber (space between lens & retina)
-maintains eye shape

Front 15

the eye is a _____ organ

Back 15

hollow
must be kept in shape of a ball for vision to occur

Front 16

how is ball shape of eye maintained?

Back 16

-gel in vitreous humor (posterior) and fluid in aqueous humor (anterior) must be present in set amounts
-that applies pressure inside the eye
-keeps it inflated

Front 17

pressure inside eye is called?

Back 17

-intraocular pressure (IOP)

Front 18

what happens if IOP is too low?

Back 18

-becomes soft & collapses
-prevents light from getting from receptors to retina

Front 19

what happens if IOP is too high?

Back 19

-extra pressure presses on blood vessels in eye
-prevents blood from flowing through = inadequate oxygen = cell funeral
-glaucoma

Front 20

conjunctivae

Back 20

mucous membranes of the eye

Front 21

muscles around eye are innervated by which cranial nerves?

Back 21

- III (oculomotor)
- IV (trochlear)
- VI (abducens)

Front 22

CN II (optic nerve)

Back 22

-sight
-connecting the optic disc to the brain

Front 23

CN V (trigeminal nerve)

Back 23

-stimulates blink reflex when cornea is touched

Front 24

CN VII (facial nerve)

Back 24

-innervates lacrimal glands & muscles controlling lid closure

Front 25

Emmetropia

Back 25

-ideal refraction of the eye

Front 26

Hyperopia

Back 26

-farsightedness
-eye does not refract light enough
-image falls behind retina
-convex lenses

Front 27

Myopia

Back 27

-nearsightedness
-eye overrefracts light
-images are focused in front of the retina
-concave lenses

Front 28

astigmatism

Back 28

-refractive error caused by unevenly curved surfaces on or in eye
-especially of the cornea
-distort vision

Front 29

for common changes in vision related to aging see chart 48-1, iggie 1075

Back 29

do it!

Front 30

presbyopia

Back 30

-lens loses elasticity as we age
-closest distance at which eye can clearly see an object increases (must hold objects farther away)
- farthest distance at which eye can clearly see an object decreases
-narrower visual field

Front 31

people with a refractive error should have eye exams how often?

Back 31

yearly

Front 32

how often should adults older than 40 have an eye exam?

Back 32

yearly

Front 33

young adults with no vision problems may need eye exams how often?

Back 33

every 3-5 yrs

Front 34

CN III (oculomotor)

Back 34

-EOM

Front 35

CN IV (trochlear)

Back 35

-EOM
-moves eyeball downward & lateral

Front 36

CN VI (abducens)

Back 36

-EOM
-moves eyeball laterally

Front 37

tonometry measures?

Back 37

IOP using tonometer

Front 38

normal IOP readings

Back 38

10-21 mm Hg

Front 39

the Amsler Grid lines look wavy in what disease?

Back 39

macular degeneration

Front 40

nursing implications for low-vision/blindness

Back 40

-safe environment
-routine places for items within environment
-place food in typical clock pattern
-self-care & safety for medication identification

Front 41

how to guide client with low-vision/blindness

Back 41

-have client hold elbow your elbow & walk a half step behind you
-warn about changes in space (steps, ramps, etc)

Front 42

Blepharitis

Back 42

-inflammation of eyelid edges
-common in elderly & dry-eye syndrome
-reduced tear production often leads to bacterial infection
-tears inhibit bacterial growth

Front 43

Blepharitis S/S

Back 43

-itchy, red, burning eyes
-Seborrhea (greasy,itch scaling) of eyebrows & eyelids

Front 44

Blepharitis interventions

Back 44

-use warm, moist compresses followed by gentle scrubbing with dilute baby shampoo
-avoid rubbing eyes

Front 45

Hordeolum

Back 45

-stye
-external: infection of sweat glands in eyelid where eyelashes exit
-internal: infection of eyelid sebaceous glands

Front 46

Hordeolum S/S

Back 46

-usually affects one eyelid at a time
-vision not affected
-small, beady, swollen areas on skin or conjunctival side of eyelid
-becomes painful

Front 47

Hordeolum interventions

Back 47

-warm compresses 4x a day followed by antibacterial ointment
-ointments may cause blurred vision, remove before driving

Front 48

Chalazion

Back 48

-inflammation of a sebaceous gland in eyelid

Front 49

chalazion S/S

Back 49

-begins with redness & tenderness
-gradual painless swelling (unlike hordeolums). protrudes inside eyelid
-eye fatigue, light sensitivity, excessive tears

Front 50

chalazion interventions

Back 50

-warm compresses 15 min 4X a day followed by ophthalmic ointment
-if large enough to affect vision, recurs frequently, cosmetically displeasing to pt. removed by surgery

Front 51

conjunctivitis

Back 51

-inflammation: exposure to allergens/irritants and is not contagious
-infection: bacterial/viral and is very contagious

Front 52

allergic conjunctivitis S/S

Back 52

-edema, burning, bloodshot eyes, excessive tears, itching

Front 53

allergic conjunctivitis treatment

Back 53

-instill vasoconstrictors, corticosteroid eyedrops, antihistamines
-try to identify allergen
-avoid using eye makeup until S/S are gone

Front 54

bacterial conjunctivitis S/S

Back 54

-"pink eye"
-blood shot, mild edema, tears, discharge

Front 55

bacterial conjunctivitis Tx

Back 55

-culture & sensitivity
-topical antibiotics

Front 56

conjunctivitis nursing implications

Back 56

-teach how to use eye drops/ointments
-wash medial to lateral
-emphasize hand washing, clean linens, no sharing
-restrictions to prevent spread

Front 57

Corneal abrasion

Back 57

-scrape/scratch of cornea that disrupts the integrity
-provides portal of entry for organisms, leading to corneal infection

Front 58

corneal abrasion most common cause

Back 58

-contact lens use

Front 59

why is corneal abrasion an emergency?

Back 59

-cornea has no separate blood supply
-cannot defend itself from infections that have the potential to permanently impair vision

Front 60

corneal abrasion S/S

Back 60

-pain, reduced vision, photophobia, eye secretions
-cloudy/purulent fluid may be present on eyelids/lashes
-hazy/cloudy cornea

Front 61

corneal abrasion interventions

Back 61

-C&S
-drug therapy: anti-infection eyedrops every hour for the first 24 hours
-teach how to apply properly
-stress importance of applying drug as often as prescribed, even at night

Front 62

cataract

Back 62

-opacity of the lens that distorts image projected onto retina
-mostly in elderly as lens loses water & increases density

Front 63

cataract risk factors

Back 63

-aging
-trauma/exposure to toxic agents
-occurs earlier with heavy sun exposure
-other diseases or ocular disorders

Front 64

cataract manifestations

Back 64

-slightly blurred vision & decreased color perception
-as lens cloudiness continues, vision may affect ADLs
-without surgery, can progress to blindness

Front 65

cataract post op care

Back 65

-no bending over, lifting greater than 20 lbs, water sports for 2 weeks
-avoid getting water in eye
-use of drops for 4-6 weeks
-usually followup with surgeon next day
-wear sunglasses until pupil responds normally to light
-patch on eye, patch on eye at night to prevent rubbing & glasses during day

Front 66

Glaucoma

Back 66

-IOP increases
-extra pressure on blood vessels in eye, prevents blood flow
-poorly oxygenated photoreceptors
-nerve tissues die
-when too many die, blindness occurs

Front 67

primary open-angle glaucoma (POAG)

Back 67

-most common form
-affects both eyes, asymptomatic at first
-fluid cannot leave eye at same rate it is produced

Front 68

common POAG causes

Back 68

-aging
-heredity
-central retinal vein occlusion

Front 69

angle-closure glaucoma

Back 69

-sudden onset, emergency
-forward displacement of iris
-movement of iris against cornea narrows/closes chamber angle

Front 70

POAG manifestations

Back 70

-gradual loss of visual fields
-foggy vision, reduced accommodation, mild aching in eyes, headaches, frequent changes in eyeglass prescriptions

Front 71

POAG late manifestations

Back 71

-seeing halos around lights
-loss of peripheral vision
-decreased visual acuity not correctable with eyeglasses

Front 72

Gonioscopy

Back 72

-test performed when IOP is high
-determines whether open-angle or closed-angle glaucoma is present
-painless

Front 73

open-angle IOP reading

Back 73

22-32 mm Hg

Front 74

angle-closure IOP reading

Back 74

30 mm Hg or higher

Front 75

drug therapy for glaucoma

Back 75

-focuses on reducing IOP pressure
-eyedrops are mainstay of control
-do not improve vision but prevent more damage
-systemic osmotic drug for angle-closure glaucoma

Front 76

teaching for glaucoma drug therapy

Back 76

-instill drops on time, don't skip doses
-when more than one drug is prescribed, wait 10-15 min between
-place pressure on corner of eye near nose immediately after eye drop to prevent systemic absorption
-stress good hand washing, keep container tip clean, avoid touching tip to any part of eye

Front 77

age-related macular degeneration (AMD)

Back 77

-deterioration of the macula (area of central vision)
-can be dry or wet

Front 78

dry AMD causes

Back 78

-most common type, age-related
-caused by gradual blockage of retinal capillaries
-rods & cones die
-retinal cells of macula die

Front 79

dry AMD manifestations

Back 79

-central vision declines
-mild blurring & distortion at first

Front 80

how to reduce risk of dry AMD and slow progression

Back 80

-increasing dietary intake of antioxidants & carotenoids

Front 81

wet AMD

Back 81

-growth of new blood vessels in the macula, which have thin walls & leak blood & fluid
-can occur at any age
-can develop in dry AMD too

Front 82

wet AMD manifestations

Back 82

-sudden decrease in vision
-complains of lines being wavy, letter being broken up

Front 83

dry AMD treatment

Back 83

-help patient maximize remaining vision (pg. 1106 Iggie)
-loss of central vision reduces ability to read, write, recognize safety hazards, and drive

Front 84

wet AMD treament

Back 84

-laser therapy to seal leaking blood vessels
-photodynamic therapy - seals/destroys leaking blood vessels

Front 85

Amsler Grid home teaching

Back 85

1.Choose a bare wall or door in a well-lighted room away from any window glare to hang up the grid.
2.Tape the test to the wall. The center dot should be at eye level.
3.Measure 14 inches from the wall with your ruler and mark this spot with tape.
4.Stand facing the wall with your heels on the tape marker.
5.Wear the glasses or contact lenses that you normally wear for reading.
6.Look at the dot in the center of the grid.
7.Cover left eye with a paper cup and continue looking at the dot. You should see all four corners of the grid.
8.If any area of the grid pattern appears distorted (ex:wavy, blurred or blank) while looking at the dot, tell helper or make a mental note.
9.Repeat this check with your right eye covered.

Front 86

emergency care for chemical burn

Back 86

-flush eye with sterile normal saline for 15-30 minutes then transport to ER or opthamologist
-if NS not available use tap water

Front 87

emergency care for corneal injury or perforating foreign body

Back 87

-do not rub eye or attempt to remove foreign body
-do not irrigate eye
-cover eye with paper cup to protect it
-get to ER or opthamologist

Front 88

Tumors of eye

Back 88

-benign or malignant tumors of orbit, eyelids, and conjunctiva
-malignant tumors of the globe = ocular melanoma

Front 89

orbital surgery

Back 89

-goals: maintain visual function & appropriate cosmetic appeal
-may use : systemic & topical antibiotics, corticosteroids, ice compresses
-elevate HOB 45 degrees
-report sudden pain/ vision changes

Front 90

enucleation

Back 90

-removal of eye and/or associated structure such as eyelid
-most common surgery for ocular melanoma
-ball implant is inserted

Front 91

ocular prothesis

Back 91

-place conformer into socket to maintain shape of orbit while suture lines heal & maintain integrity of eyelids
-base for prosthesis

Front 92

visual acuity test for infants

Back 92

-ability to follow object
-pupillary light reflex
-blink reflex to bright light
-assess for coordinated motor function

Front 93

visual acuity test for toddlers

Back 93

-Allen test
-corneal light reflex to assess for strabismus

Front 94

visual acuity test for preschoolers

Back 94

-Snellen E chart

Front 95

visual acuity test for school-age

Back 95

-Snellen E chart until child can read and verbalize letters
-assess color perception

Front 96

visual acuity tests for adults & elders

Back 96

-Snellen chart
-Jaeger cards

Front 97

corneal light reflex test

Back 97

-determines alignment of eyes
-ask pt to stare straight ahead
-shine pen light at both corneas from distance of 12-15 feet
-bright dot of light reflected should be in a symmetric position. ex: 1 o'clock in right eye, 11 o'clock in left

Front 98

what is legal blindness?

Back 98

20/200