Sensory System Chapter 51, 52

Front 1

Oculomotor, trochlear, and abducens cranial nerves do what?

Back 1

Work as extrinsic and rectus muscles of the eye

Front 2

Wall of the eye has how many layers?

Back 2

3; Outer sclera, middle choroid, inner retina.

Front 3

What is the first part of the eye that refracts light rays

Back 3

Transparent Cornea

Front 4

Choroid layer of eye contains

Back 4

blood vessels, melanin that absorbs light to protect eyeball from glare

Front 5

What parts of the eyes have no capillaries?

Back 5

Cornea, ciliary body

Front 6

Constriction of the eye is a __________ response.

Back 6

sympathetic

Front 7

Contraction of the eye is a ______________ respone.

Back 7

parasympathetic

Front 8

Retina lines what?

Back 8

The posterior two thirds of the eyeball and contains the cones and rodes.

Front 9

Cones

Back 9

detect color

Front 10

Rods

Back 10

Detect light

Front 11

Optic disc

Back 11

Can be called the blind spot because no rods or cones are present

Front 12

Larger posterior cavity of the eye contains

Back 12

Vitreous humor and is between the lens and retina.
Vitreous humor keeps retina in place.

Front 13

Anterior cavity of the eye contains

Back 13

Aqueous humor, which nourishes the lens and cornea.
Aqueous humor is formed by capillaries, flows anteriorly through pupil and reabsorbed by canal of Schlemm.
Reabsorption normally equals rate of production.

Front 14

The ____ is the only adjustable part of the focusing system.

Back 14

Lens

Front 15

When the eye focuses on a distant item...

Back 15

Ciliary muscle is relaxes and lens is elongated and thin

Front 16

When the ye focuses on a close object...

Back 16

Ciliary muscles contract and form a smaller circle.

Front 17

Light absorbing molecule....

Back 17

Retinal
(A derivative of vitamin A)
..Which binds to a protein called opsin

Front 18

In rods the light stiulates

Back 18

The breakdown of rhodopsin into opsin and retinal which results in nerve impulse for transmission

Front 19

Cones also contain

Back 19

Retinal.
Opsins of the cones respond to visible light spectrum (red-absorbing, blue-absorbing, green-absorbing)

Front 20

Impulses from rods and cones are transmitted to

Back 20

Ganglion neurons

Front 21

The optic nerves of both eyes converge at

Back 21

the optic chiasma in front of the pituitary gland

Front 22

When two images are put together is called

Back 22

binocular vision which also provides depth perception

Front 23

Most common changes in the aging eye is

Back 23

The lens

Front 24

Lens may become

Back 24

Partially or totally opaque and loses elasticity

Front 25

Most people become ________ sighted as they age.

Back 25

Far
May need corrective lenses at age 40

Front 26

Things that happen to aging eye

Back 26

Peripheral vision loss
Depth perception decreases
Color vision fades (red yellow orange are best seen)

Front 27

Tests used for visual acuity

Back 27

Snellens chart, E chart, hand-held visual acuity chart (Rosenbaums card)

Front 28

Visual impairement occurs at....

Back 28

20/70

Front 29

Legal blindeness =

Back 29

20/200

Front 30

E chart is used for patients who are

Back 30

Illiterate

Front 31

Peripheral vision tests are also called

Back 31

Testing visual fields by confrontation

Front 32

Nystagmus

Back 32

Involuntary cyclical rapid movement of the eyes in response to vertical horizontal or rotary movement

Front 33

Cover test

Back 33

Used for abnormal corneal light reflex to evaluate muscle balance

Front 34

Tropia

Back 34

Deviation of eye away from visual axis

Front 35

Esotropia

Back 35

Deviation of the eye toward the nose

Front 36

Exotropia

Back 36

Eye movement laterally

Front 37

Hypotropia

Back 37

Downward deviation of eye

Front 38

Consensual response

Back 38

Both pupils constrict

Front 39

Accommodation

Back 39

Ability of pupil to respond to near and far distances

Front 40

PERRLA

Back 40

Pupils equal, round, reactive to light, accommodation

Front 41

Presbycusis

Back 41

Hearing loss
Due to loss of hair cells and decreased blood supplying ear

Front 42

Palpebral Fissure

Back 42

Distance b/w upper and lower eyelid

Front 43

Pterygium

Back 43

Thickening of conjunctiva

Front 44

Arcus Senilus

Back 44

Older than 40, bilateral opaque whitening of outer rim of cornea caused by lipid deposits
Doesnt affect vision

Front 45

Tonometer

Back 45

Test IOP

Front 46

Fluoresein Angiography

Back 46

Used to monitor, diagnose, treat eye diseases.
Uses dye

Front 47

Electroretinography

Back 47

Diagnosing diseased of the rods and cones.
Contact lense with electrodes directly on eye

Front 48

Ultrasonography

Back 48

Eye anesthetized with drops and probe is put on eye for ultrasound

Front 49

Corneal damage and night blindness are r/t

Back 49

Lack of vitamin A

Front 50

Optic neuritis is r/t

Back 50

Lack of vitamin B

Front 51

Macular degeneration and cataracts r/t

Back 51

Lack of antioxidants

Front 52

Reduce change of MD by 27% with

Back 52

High doses of vit C, E, beta carotene and zinc
Spinach, broccoli and eggs reduce risk by 40%

Front 53

60% reduction of risk of cataracts with

Back 53

Vitamin C supplements for 10 years or more

Front 54

Punctum

Back 54

Tear duct
Hold punctum after admin meds to eye to prevent systemic reaction to med

Front 55

Three Auditory Bones

Back 55

Malleus, Incus, Stapes

Front 56

Rinne Test

Back 56

Normal AC>BC 2:1
Conductive loss= BC>AC
Sensorineural loss= AC>BC less than 2:1

Front 57

Webers Test

Back 57

Tuning fork on top of head
Conductive loss= Sound louder in ear thats affected
Sensorineural loss= Sounds better in good ear

Front 58

DX Tests for hearing

Back 58

Audiometric testing= headphones/raise hand
Tympanometry= Find hole in ear via pressure
Caloric Test= Assess cranial nerve 8, squirt cold or hot water in ear and watch for nystagmus
Electronystagmogram= Find unilateral hearing loss w/electrodes

Front 59

Unsafe lvl of noise

Back 59

90dB

Front 60

Conjunctivitis

Back 60

Inflammation of conjunctiva
Viral or bacterial
Bacterial=Pink eye
Can be caused by decongestant eye drops that vasocontrict
-Trachoma-form of conjunctivitis (Eyelids shrink)

Front 61

Mannitol (Osmotic)

Back 61

Reduce IOP

Front 62

Atropine (Mydriatics)

Back 62

Dilate pupils

Front 63

Blepharitis

Back 63

Inflammation of eyelid margins
Two Types:
Seborrheic blepharitis= Red eyes, scales, flaking
Ulcerative blepharitis= Crust, red eyes, inflammed corneas

Front 64

Hordeolum

Back 64

Staph abscess in sebaceous gland
Sty/Spontaneously heals in 24-36hrs

Front 65

Chalazion

Back 65

Bigger abscess in meibornian glands
Internal
May need surgically drained

Front 66

Keratitis

Back 66

Inflammation of cornea
Herpes simplex keratitis most common
Painful

Front 67

Hyperopia (Farsightedness)

Back 67

Rays focus behind retina
Corrected with convex lenses

Front 68

Myopia (Nearsightedness)

Back 68

Rays focus in front of retina
Corrected with concave lenses

Front 69

Astigmatism

Back 69

Unequal curvatures in cornea
Blurred vision with distortion

Front 70

Presbyopia

Back 70

Lose elasticity, decreased ability to focus on close objects.
Usually after age 40

Front 71

Cycloplegic drugs

Back 71

Dilate pupil and paralyze ciliary muscles temporarily

Front 72

Diabetic Retinopathy

Back 72

Changes in retinal blood vessels
Found in diabetic pts
1)Background retinopathy=Microaneurysms
2)Preproliferative retinopathy= dilated veins (blocked/sluggish blood flow)
3)Proliferative retinopathy= formation of new blood vessels

May need vitrectomy

Front 73

Retinal Detachment

Back 73

Separation of retina from choroid layer of eye that allows fluid to enter between layers

Front 74

Rhegmatogenous retinal detachment

Back 74

Hole or tear in retina

Front 75

Nonrhegmatogenous Tractional Detachment

Back 75

Pulls retina away from normal position
Occurs in pts with sickle cell disease or DM

Front 76

Exudative Detachment

Back 76

Fluid or exudate accumulates and separates layers

Front 77

S/S of Retinal Detachment

Back 77

No pain
See "floaters", cobwebs, darkness.

Front 78

DX Test for Retinal Detachment

Back 78

Indirect ophthalmoscopy to examine eye inside/ looks bumpy instead of smooth

Front 79

Laser Reattachment

Back 79

Causes controlled burn and adheres layers together again.
Used for small areas only

Front 80

Cryosurgery

Back 80

Probe on sclera causes injury to tissue forming an adhesion

Front 81

Electrodiathermy

Back 81

(Least used)
Needles into sclera to drain, retina later adheres to choroid layer

Front 82

Sclera Buckling

Back 82

Silicon implant in conjuction with beltlike device around sclera to bring choroid in contact with retina (Cryo or laser first to repair)

Front 83

Pneumatic Retinopexy

Back 83

Injects gas or air into chamber to hold retina in place
Recline for 16hrs preop
Recline 8 hours a day for 3 weeks postop

Front 84

Glaucoma

Back 84

Increased IOP
Pressure causes damage to optic nerve
Damage is silent, progressive, irreversible

Front 85

AACG

Back 85

Narrowed angle where iris meets cornea, blocking flow of AH.
MEDICAL EMERGENCY
S/S: Rainbows around light
DONT GIVE MYDRIATICS=DILATE

Front 86

POAG

Back 86

Trabecular meshwork and Schlemms canal degenerate and block AH
S/S: Halos around lights

Front 87

Treatment for Glaucoma

Back 87

Miotics--Isopto, Pilocar (constrict pupil
Anhydrase inhibitors--Propine, beta blockers Timoptic
Steroid eye drops to decrease inflam

Front 88

Cataracts

Back 88

Opacity in the lens of the eye
Light rays unable to get to retina
Increases risk: UV rays, DM, smoking, alcohol
S/S: Halos around eyes

Front 89

Macular Degeneration

Back 89

Leading cause of visual impairement
Deterioration in macula, area on retina where lights converge for sharp central vision needed for reading and seeing small objects
Macula is responsible for color vision

TWO TYPES: Dry and Wet

Front 90

Dry Form of Macular Degeneration

Back 90

(Atrophic)
Photoreceptors in macula fail to function and not replaced r/t aging
70-90% of cases
SLOW ONSET

Front 91

Wet Form of Macular Degeneration

Back 91

Retinal tissue degenerates allowing vitreous fluid or blood into subretinal space.
New blood vessels are formed and compromise macular tissue causing edema.
Scars are formed and limit central vision
SUDDEN ONSET

Front 92

Amsler grid

Back 92

Helps dx MD

Front 93

Wet Type of ARMD is treated with...

Back 93

Argon laser photocoagulation
Meds:Macugen, Lucentis

Front 94

Chemical Eye Burns need irrigated for

Back 94

15-20 minutes of water

Front 95

Enucleation

Back 95

Entire removal of eyeball

Front 96

Conductive Hearing Loss

Back 96

Due to obstruction of sound waves from reaching inner ear.
Mechanical problem

Front 97

Sensorineural Hearing Loss

Back 97

Originates in cochlea and involves hair cells and nerve endings. Originates in nerve or brainstem.
Caused by disease or trauma of inner ear.

Front 98

Pts with presbycusis cant decipher high frequency sounds such as

Back 98

Consonants like s,z,t,f,g

Front 99

Ear Canal Furuncle

Back 99

Infection of hair follicle
Erupt and drain spontaneously

Front 100

Perichondritis

Back 100

Infection of auricle, can result in necrosis of carilage

Front 101

Repeated infections in middle ear can cause

Back 101

cholesteatoma cystlike sac

Front 102

Typanosclerosis

Back 102

Complication of repeated middle ear infections
Deposits of collagen and calcium on tympanic membrane

Front 103

Myringotomy

Back 103

Drain of tympanic membrane of fluid

Front 104

Most ear tubes spontaneously extrude at

Back 104

3-12 mnths

Front 105

Myringoplasty

Back 105

Reconstruction of tympanic membrane
-One type used Gelfoam over perforation

Front 106

Otosclerosis

Back 106

Formation of new bone along stapes causing it to become immobile causing a conductive hearing loss

Pink/Orange tympanic membrane

Front 107

Stapedectomy

Back 107

Stapes removed and replaced with prosthesis

Front 108

Labyrinthitis

Back 108

Inflammation or infection of inner ear
Usually due to alcohol consumption
Nystagmus on affected side

Front 109

Acoustic Neuroma

Back 109

Tumor of 8th cranial nerve
Most common benign tumor

Front 110

Menieres Disease

Back 110

Balance disorder
Dilation of membranous labyrinth

Front 111

If pt has acute angle closure glaucoma dont give

Back 111

Atropine or Vistaril and Benadryl

Front 112

Lasix can cause

Back 112

Hearing loss