Chapter 20 - Eye

Question 1

Three layers of the eyeball

Answer 1

Outer - scleral
uveal
Retinal layer

Question 2

where is the first refraction of light?

Answer 2

cornea

Question 3

where is the second refraction of light?

Answer 3

lens

Question 4

what structure can accommodate its shape to see far away or close up?

Answer 4

lens

Question 5

what shape does the lens take during accommodation?

Answer 5

rounded

Question 6

where are photoreceptors?

Answer 6

retina

Question 7

rods

Answer 7

light

Question 8

cones

Answer 8

acuity, color

Question 9

what structure provides the greatest visual acuity?

Answer 9

macula (post on the retina)

Question 10

what structure provides the best vision?

Answer 10

fovea

Question 11

what fluid cleans the lens and retina?

Answer 11

aqueous humor

Question 12

what glands produce tears?

Answer 12

lacrimal

Question 13

what is strabismus?

Answer 13

crossed eyes

Question 14

etiology of strabismus

Answer 14

eye muscles don’t work together and it confuses the brain. the brain then ignores image from the weaker eye causing ambylyopia (lazy eye)

Question 15

what is nystagmus?

Answer 15

fast uncontrollable eye movements in one or both eyes

Question 16

etiology of nystagmus

Answer 16

congenital or acquired from head injury, stroke, inner ear disorders, or drugs/medication (most common)

Question 17

sneller eye chart

Answer 17

how much you can see from 20 ft away (20/20),

Question 18

ophthalmoscope

Answer 18

tool used to examine the retina

Question 19

tonometer

Answer 19

tool used to measure intra-ocular pressure

Question 20

slit-lamp

Answer 20

tool used to examine the cornea, iris, and lens

Question 21

hyperopia

Answer 21

farsighted, trouble seeing close up

Question 22

myopia

Answer 22

nearsighted, trouble seeing far away (more common)

Question 23

presbyopia

Answer 23

vision loss with age

Question 24

astigmatism

Answer 24

curvature in cornea

Question 25

symptoms of myopia

Answer 25

blurred vision, squinting when looking at far objects

Question 26

symptoms of hyperopia

Answer 26

difficulty focusing on near objects

Question 27

treatment for refractive disorders

Answer 27

LASIK - both disorders lens implant - myopia (nearsightedness only)

Question 28

treatment for myopia

Answer 28

concave lenses

Question 29

treatment for hyperopia

Answer 29

convex lenses

Question 30

treatment for astigmatism

Answer 30

glasses or hard contact lenses

Question 31

presbyopia treatment

Answer 31

reading glasses or bifocal lenses

Question 32

what is conjunctivitis

Answer 32

inflammation of the conjunctiva *pink eye

Question 33

is pink eye contagious?

Answer 33

yes

Question 34

what is the cause of conjunctivitis?

Answer 34

bacterial (most common), fungal, viral, or related to injury

Question 35

corneal keratitis

Answer 35

infection of cornea, unilateral, leads to scarring -->vision loss

Question 36

corneal keratopathy (band)

Answer 36

calcium deposits within cornea, creates a band -- pain, decreased acuity

Question 37

corneal dystrophy

Answer 37

clouding of cornea from abnormal accumulation *bilateral *genetic

Question 38

is corneal dystrophy genetic?

Answer 38

yes

Question 39

cataracts

Answer 39

cloudy lens

Question 40

what is the leading cause of blindness in adults?

Answer 40

cataracts

Question 41

is cataracts age associated?

Answer 41

yes - 90% of adults have some by 65

Question 42

treatment for cataracts

Answer 42

LASIK surgery `

Question 43

glaucoma

Answer 43

damaged optic nerve from increased intraocular pressureis

Question 44

is glaucoma reversible or irreversible?

Answer 44

irreversible

Question 45

why does IOP increase with glaucoma?

Answer 45

there's a buildup of aqueous humor from the ciliary body

Question 46

what is a common symptom of glaucoma?

Answer 46

light halos

Question 47

is glaucoma an emergency?

Answer 47

yes - possible loss of vision within 1 day

Question 48

risk factors for glaucoma

Answer 48

age refractive disorders genetics other diseases (hypertension and diabetes)

Question 49

retinal detachment

Answer 49

retina peels away from support tissue

Question 50

is retinal detachment an emergency?

Answer 50

yes - can lead to blindness

Question 51

symptoms of retinal detachment

Answer 51

spots, floaters, and flashes of light -- NOT painful

Question 52

Etiology of retinal detachment

Answer 52

trauma to eye Marfan syndrome extreme nearsightedness

Question 53

How do reattach the retina? - treatment

Answer 53

surgery to reattach

Question 54

macular degeneration

Answer 54

damage to macula - does not lead to complete loss of vision

Question 55

what is the leading cause of vision loss in people over 60?

Answer 55

macular degeneration

Question 56

risk factors for macular degeneratation

Answer 56

age obesity UV light exposure smoking family history ethnicity

Question 57

what is the treatment for macular degeneration?

Answer 57

no cure

Question 58

symptom of macular degeneration

Answer 58

blurry dark spot in the middle of visual field

Question 59

hypertensive retinopathy

Answer 59

damage to retina due to hypertension

Question 60

hypertensive retinopathy symptoms

Answer 60

dim vision vision loss double vision

Question 61

is hypertensive retinopathy reversible?

Answer 61

yes - with treatment

Question 62

diabetic retinopathy

Answer 62

damage to blood vessels in retina from diabetes

Question 63

what can diabetic retinopathy lead to?

Answer 63

microhemorrhages edema neovascularization (new blood vessels)

Question 64

symptoms of diabetic retinopathy

Answer 64

spots/floaters in eyes blurred vision empty spot in vision

Question 65

treatment for diabetic retinopathy

Answer 65

blood glucose control surgery to seal leaky vessels

Question 66

how many more times are diabetics to go blind than normal people?

Answer 66

20x more likely

Question 67

other diseases in diabetics

Answer 67

glaucoma retinal detachment cataracts diabetic retinopathy

Question 68

color blindness

Answer 68

deficiency of certain cones

Question 69

red-green color vision defects

Answer 69

deficiency in red/green cones

Question 70

blue-yellow color vision defects

Answer 70

trouble differentiating shades of blue and green

Question 71

what type of genetic disease is color blindness?

Answer 71

X-linked Autosomal recessive

Question 72

retinoblastoma

Answer 72

cancer of the eye in children

Question 73

what type of genetic disease is retinoblastoma?

Answer 73

autosomal dominant - Rb1 gene

Question 74

malignant melanoma

Answer 74

cancer of the eye in adults -- arise from melanocytes in the choroid layer and iris

Question 75

malignant melanoma has a worse prognosis than ....... melanoma

Answer 75

skin

Question 76

what is the definition of blindness

Answer 76

visual acuity of 20/200

Question 77

causes of blindness

Answer 77

lesions developmental causes trauma