eyes Flashcards

Question

visual pathways and visual fields

Answer 1

Light rays are refracted through transparent media, the cornea, aqueous humor, lens, and vitreous body, striking the retina ◦ Retina transforms light stimulus into nerve impulses conducted to visual cortex ◦ Image formed on retina is upside down and reversed ◦ All retinal fibers collect to form optic nerve but maintain same spatial arrangement ◦ At optic chiasm, fibers from both visual fields cross over ◦ Left optic tract now has fibers from left half of each retina, and right optic tract contains fibers only from right; thus, right side of brain looks at left side of the world

Answer 2

Pupillary light reflex: normal constriction of pupils when bright light shines on retina ◦ Subcortical reflex arc with no conscious control

Answer 3

Fixation: a reflex direction of eye toward an object attracting a person’s attention ◦ Image fixed in center of visual field, the fovea centralis

Answer 4

the ability for adaptation of the eye for near vision

Answer 5

◦ Accomplished by increasing curvature of lens through movement of ciliary muscles ◦ Although lens cannot be observed directly, the following components of accommodation can be observed: ◦ Convergence (motion toward) of the axes of the eyeballs ◦ Pupillary constriction

Answer 6

- Changes in eye structure  loss of elasticity, fat & muscle tissue atrophy &decreased tear production - Visual acuity may diminish gradually after age 50 and more so after age 70 Floaters appear from accumulation of debris

Answer 7

Presbyopia ◦ Lens loses elasticity, becoming rigid and glasslike, which decreases the ability to change shape to accommodate for near vision by age 40 to 45

Answer 8

cataract formation diabetic retinopathy (DR) glaucoma Age-related macular degeneration (AMD)

Answer 9

lens opacity, resulting from a clumping of proteins in the lens

Answer 10

oxidative damage and inflammation of the retina leading to blindness

Answer 11

increased intraocular pressure leading to optic nerve compression

Answer 12

degeneration of the cells in the macula of the retina leading to a loss of central vision

Answer 13

Culturally based variability present in color of iris and retinal pigmentation - By age 80, most individuals in the US have cataracts or have had cataract surgery ◦ Family history & environment are risk factors Glaucoma incidence increases with age. ◦ Black Americans 40 years & older are at highest risk, followed by Hispanic/Latinos & Whites (NIH, 2021)

Answer 14

* Increase seen in White Americans over the age of 75 (NIH,2021) * Diet & smoking are modifiable risk factors

Answer 15

* Not being able to see letters on the eye chart at line 20/40 or below (NIH, 2021) * Due to uncorrected refractive error * Most common eye problems in children uncorrected refractive errors (nearsightedness, farsightedness & astigmatism) * Visual screening is crucial to detect strabismus (“cross-eye”) & amblyopia (“lazy eye”)

Answer 16

- Vision difficulty: decreased acuity, blurring, blind spots - Pain - Strabismus, diplopia - Redness, swelling - Watering, discharge - History of ocular problems - Glaucoma - Use of glasses or contact lenses - Patient-centered care

Answer 17

Any difficulty seeing or any blurring? Blind spots? Come on suddenly or slowly? One eye or both? Constant, or does it come and go? Do objects appear out of focus or clouding of objects? Do spots move in front of your eyes? One or many? In one or both eyes? Any halos, rainbows, rings around objects? Any blind spot? Does it move as you shift your gaze? Any loss of peripheral vision? Any night blindness?

Answer 18

Any eye pain? Please describe. Come on suddenly? Quality: burning or itching? Or sharp, stabbing pain; pain with bright light? A foreign body sensation? Or deep aching? Or a headache in the brow area?

Answer 19

 Any history of crossed eyes?  Now or in the past?  Does this occur with eye fatigue?  Ever see double?  Constant, or does it come and go?  In one eye or both?

Answer 20

 Any redness or swelling in the eyes?  Any infections?  Now or in the past?  When do these occur?  In a particular time of year?

Answer 21

◦ Any watering or excessive tearing? ◦ Any discharge? Any matter in the eyes? Is it hard to open your eyes in the morning? What color is the discharge? ◦ How do you remove matter from eyes?

Answer 22

Any history of injury or surgery to eye? Any history of allergies?

Answer 23

◦ Have you ever been tested for glaucoma? What were the results? ◦ Do you have any family history of glaucoma?

Answer 24

◦ Do you wear glasses or contact lenses? How do they work for you? ◦ Last time your prescription was checked? Was it changed? ◦ If you wear contact lenses, are there any problems such as pain, photophobia, watering, or swelling? ◦ How do you care for contacts? How long do you wear them? How do you clean them? Do you remove them for certain activities?

Answer 25

- Last vision test? Ever tested for color? - Any environmental conditions at home or at work that may affect your eyes? If so, do you wear goggles to protect your eyes? - What medications are you taking? Systemic or topical? Any specifically for eyes? - Do you smoke? - If you have experienced a vision loss, how do you cope? Do you have books with large print, books on audio tape, braille? - Do you maintain living environment the same? - Do you sometimes fear complete loss of vision?

Answer 26

Have you noticed any visual difficulty with climbing stairs or driving? Any problem with night vision? When was last time tested for glaucoma? ◦ Any aching pain around eyes? Any loss of peripheral vision? ◦ If you have glaucoma, how do you manage your eyedrops? Is there history of cataracts? Any loss or progressive blurring of vision? Do your eyes ever feel dry or burning? What do you do for this? Any decrease in usual activities, such as reading or sewing?

Answer 27

position the person standing for the vision screening; then sitting up with their head at your eye level

Answer 28

* Snellen eye chart * Handheld visual screener * Opaque card or occluder * Penlight * Ophthalmoscope * Applicator stick (occasionally)

Answer 29

Snellen alphabet chart is most used and accurate measure of visual acuity ◦ It has lines of letters arranged in decreasing size ◦ Place chart in a well-lit spot at eye level; position the person exactly 20 feet from chart; hand the person an opaque card with which to shield one eye at a time during test ◦ If the person wears glasses or contact lenses, leave them on; remove only reading glasses ◦ Ask the person to read through chart to smallest line of letters possible; encourage trying next smallest line also

Answer 30

If the person is unable to see even largest letters, shorten distance to chart until the person sees it, and record that distance (e.g., 10/20) If visual acuity even lower, assess whether the person can count your fingers when they are spread in front of eyes or distinguish light perception from your penlight

Answer 31

For those who report increasing difficulty reading Test near vision with handheld vision screener with various sizes of print (e.g., a Jaeger card) * Hold card in good light about 35 cm (14 inches) from the eye; this distance equals print size on 20-foot chart * Test each eye separately, with glasses on * Normal result is “14/14” in each eye, read without hesitancy and without moving card closer or farther away * When no vision screening card is available, ask the person to read from a magazine or newspaper

Answer 32

a gross measure of the peripheral vision; it compares the person's peripheral vision with that of yours

Answer 33

◦ Position yourself at eye level with the person about 2 feet away ◦ Direct the person to cover one eye with an opaque card and with other eye to look straight at you ◦ Cover your own eye opposite to the person’s covered one; you are testing the uncovered eye ◦ Hold pencil or your finger as target midline between you and the person, and slowly advance it in from periphery in several directions *Ask the person to say “now” as a target is first seen; this should be just as you see the object also *Estimate angle between the anteroposterior axis of the eye and the peripheral axis where the object is first seen * Normal results are about 50 degrees upward, 90 degrees temporal, 70 degrees down, and 60 degrees nasal *Sensitivity can be increased by combining a wiggling finger with a moving red target

Answer 34

the Hirschberg test

Answer 35

* Assess parallel alignment of eye axes by shining a light toward the person’s eyes * Direct the person to stare straight ahead as you hold the light about 30 cm (12 inches) away * Note the reflection of light on the corneas; should be in exactly the same spot on each eye

Answer 36

Leading patient through six cardinal positions of gaze: ◦ Follow the movement of penlight or object proceeding clockwise ◦ Assess for potential EOM muscle weakness, nystagmus, or lid lag

Answer 37

◦ Already you will have noted the person’s ability to move around room, with vision functioning well enough to avoid obstacles and to respond to your directions ◦ Also note facial expression; relaxed expression accompanies adequate vision Eyebrows ◦ Look for symmetry between the two eyes ◦ Normally eyebrows are present bilaterally, move symmetrically as expression changes, and have no scaling or lesions

Answer 38

◦ Upper lids normally overlap superior part of iris, and approximate completely with lower lids when closed ◦ Note that eyelashes are evenly distributed along lid margins and curve outward

Answer 39

◦ Eyeballs are aligned normally in their sockets with no protrusion or sunken appearance ◦ Blacks normally may have slight protrusion of eyeball beyond supraorbital ridge

Answer 40

Ask the person to look up; using thumbs, slide lower lids down along orbital rim, being careful not to push against eyeball ◦ Inspect exposed area; eyeball should look moist and glossy ◦ Numerous small blood vessels normally show through transparent conjunctiva - Otherwise, conjunctivae clear and show normal color of structure below; pink over lower lids and white over sclera - Note any color change, swelling, or lesions - Be aware of ethnic variations

Answer 41

Ask the person to look down; with thumbs, slide outer part of upper lid up along bony orbit to expose under lid; inspect for any redness or swelling ◦ Normally puncta drain tears into lacrimal sac ◦ Presence of excessive tearing may indicate blockage of nasolacrimal duct Check by pressing index finger against sac, just inside lower orbital rim, not against side of the nose ◦ Pressure will slightly evert lower lid, but there should be no other response to pressure

Answer 42

Shine light from side across cornea, and check for smoothness and clarity ◦ Oblique view highlights any abnormal irregularities in corneal surface There should be no opacities (cloudiness) in cornea, anterior chamber, or lens behind the pupil ◦ Do not confuse an arcus senilis with an opacity; arcus senilis is normal finding in aging persons

Answer 43

Iris normally appears flat, with round regular shape and even coloration ◦ Note size, shape, and equality of pupils; normally pupils appear round, regular, and of equal size in both eyes

Answer 44

◦ Darken room and ask person to gaze into distance; this dilates pupils; advance a light in from side and note response ◦ Normally you will see constriction of same-sided pupil (a direct light reflex) and simultaneous constriction of the other pupil (a consensual light reflex) ◦ In acute care setting, pupil size is measured in millimeters before and after the light reflex

Answer 45

Test for accommodation by asking the person to focus on a distant object ◦ This dilates pupils; then have the person shift gaze to near object, such as your finger held about 7 to 8 cm (3 inches) from nose Normal response includes ◦ pupillary constriction ◦ convergence of axes of eyes - Record normal response to all these maneuvers as PERRLA, or Pupils Equal, Round, React to Light, and Accommodation

Answer 46

it enlarges the view of the eye so that you can better see it

Answer 47

they control the focus of the unit with the unit of strength measurement known as the diopeter

Answer 48

* inspect media (anterior chamber, lens, vitreous) and the ocular fundus (internal surface of retina)

Answer 49

* Black numbers indicate positive diopter; they focus on nearer objects * Red numbers show negative diopter and focus on objects farther away

Answer 50

To examine a person ◦ Darken room to help dilate pupils; dilating eyedrops are not needed during a screening examination ◦ Select large round aperture with white light for routine examination ◦ If pupils are small, use smaller white light ◦ Ask a person to please keep looking at mark on wall across room ◦ Staring at distant fixed object helps to dilate pupils and to hold retinal structures still

Answer 51

To examine a person ◦ Begin about 25 cm (10 inches) away from a person at angle of 15 degrees to the person’s line of vision ◦ Observe for presence of red reflex and steadily move closer to eye ◦ If you lose red reflex, adjust angle to find it again ◦ As you advance, adjust lens to #6 and note any opacities in media; these appear as dark shadows or black dots interrupting red reflex; normally, none is present ◦ Progress toward the person until foreheads almost touch

Answer 52

◦ Adjust diopter to bring ocular fundus into sharp focus; if you and a person have normal vision, this should be at 0 ◦ Moving diopters compensates for near- or farsightedness ◦ Use red lenses for nearsighted eyes ◦ Use black lenses for farsighted eyes ◦ Moving in on 15-degree lateral line should bring your view just to optic disc ◦ If disc is not in sight, track a blood vessel as it grows larger and it will lead to disc

Answer 53

optic disc retinal vessels general background macula

Answer 54

Most prominent landmark is optic disc, located on nasal side of retina; explore these characteristics: ◦ Color: creamy yellow-orange to pink ◦ Shape: round or oval ◦ Margins: distinct and sharply demarcated, although nasal edge may be slightly fuzzy ◦ Cup-disc ratio: distinctness varies; when visible, physiologic cup is brighter yellow white than rest of disc; width not more than one half disc diameter

Answer 55

scleral crescent pigment crescent

Answer 56

gray-white new moon shape occurs when pigment absent in choroid layer looking directly at sclera

Answer 57

black due to accumulation of pigment in choroid

Answer 58

Diameter of disc (DD) is standard measure for other fundus structures. - To describe finding, note its clock-face position and relationship to disc in size and distance (e.g., at 5:00, 3 DD from disc)

Answer 59

Only place in body where you can view blood vessels directly ◦ Many systemic diseases that affect vascular system show signs in retinal vessels

Answer 60

◦ Number: paired artery and vein pass to each quadrant; vessels look straighter at nasal side ◦ Color: arteries brighter red than veins; also have arterial light reflex, with thin stripe of light down middle ◦ A:V ratio: ratio comparing artery-to-vein width is 2:3 or 4:5 ◦ Caliber: arteries and veins show a regular decrease in caliber as they extend to periphery

Answer 61

artery and vein may cross paths; not significant if within 2 DD of disc and if no sign of interruption in blood flow is seen; should be no indenting or displacing of vessel

Answer 62

mild vessel twisting when present in both eyes is usually congenital and not significant

Answer 63

present in veins near disc as their drainage meets intermittent pressure of arterial systole; often hard to see

Answer 64

◦ Color normally varies from light red to dark brown-red; view of fundus should be clear; no lesions should obstruct retinal structures

Answer 65

◦ 1 DD in size, located 2 DD temporal to disc ◦ Inspect last in funduscopic examination; bright light causes some watering, discomfort, and pupillary constriction * Normal color somewhat darker than rest of fundus but even and homogeneous * Clumped pigment may occur with aging

Answer 66

Used when one suspects foreign body or eye pain - Procedure may cause apprehension; therefore, use a deliberate approach. ◦ Multi-step procedure using applicator stick - Inspect for color change, swelling, lesion, or evidence of foreign body

Answer 67

◦ Perform same examination as described in adult section ◦ Central acuity may decrease, particularly after 70 years of age; peripheral vision may be diminished

Answer 68

◦ Eyebrows may show loss of outer one third to one half of hair because of decrease in hair follicles; remaining brow hair is coarse ◦ As a result of atrophy of elastic tissues, skin around eyes may show wrinkles or crow’s feet; upper lid may be so elongated as to rest on lashes, resulting in pseudoptosis ◦ Eyes may appear sunken from atrophy of orbital fat; orbital fat may herniate, causing bulging at lower lids and inner third of upper lids ◦ Lacrimal apparatus may decrease tear production, causing eyes to look dry and lusterless and the person to report a burning sensation ◦ Pingueculae commonly show on the sclera

Answer 69

Ocular structures ◦ Cornea may look cloudy with age ◦ Arcus senilis is commonly seen around the cornea. ◦ Gray-white arc or circle around limbus due to deposition of lipid material ◦ As more lipids accumulate, cornea may look thickened and raised, but arcus has no effect on vision ◦ Xanthelasma: soft, raised yellow plaques occurring on lids at inner canthus ◦ They commonly occur around fifth decade of life and more frequently in women, occur with both high and normal levels of cholesterol, and have no pathologic significance

Answer 70

◦ Pupils small in old age; pupillary light reflex may be slowed ◦ Lens loses transparency and looks opaque

Answer 71

◦ Retinal structures generally have less shine; blood vessels look paler, narrower, and attenuated; arterioles appear paler and straighter, with a narrower light reflex ◦ Drusen, or benign degenerative hyaline deposits, are normal development on retinal surface ◦ Often symmetrically placed in eyes with no effect on vision

Answer 72

◦ Esotropia—inward turning of the eye ◦ Exotropia—outward turning of the eye

Answer 73

a uncovered eye and a covered eye

Answer 74

paralysis that indicates the cranial nerve dysfunction

Answer 75

Periorbital edema Exophthalmos (protruding eyes) Enophthalmos (sunken eyes) Ptosis (drooping upper lid) Upward palpebral slant Ectropion (eversion) Entropion (inversion)

Answer 76

Blepharitis (inflammation of the eyelids) Chalazion Hordeolum (stye) Dacryocystitis (inflammation of the lacrimal sac) Basal cell carcinoma

Answer 77

Unequal pupil size—Anisocoria Monocular blindness Constricted and fixed pupils—Miosis Dilated and fixed pupils—Mydriasis Argyll Robertson pupil Tonic pupil (Adie’s pupil) Cranial nerve III damage Horner’s syndrome

Answer 78

◦ Macula central blind area (e.g., Diabetes) ◦ Localized damage (Blind spot – scotoma) ◦ Increasing intraocular pressure (Glaucoma) ◦ Retinal detachment (shadow or diminished vision) Lesion in the globe or optic nerve ◦ One blind eye or unilateral blindness Lesion at optic chiasm ◦ Pituitary tumor Lesion of outer uncrossed fibers at the optic chiasm ◦ Aneurysm Lesion R optic tract or R optic radiation

Answer 79

differences in visual field losses may occur

Answer 80

Conjunctivitis Allergic conjunctivitis Iritis (circumcorneal redness) Primary angle-closure glaucoma (PACG) Subconjunctival hemorrhage Herpes simplex virus (HSV)

Answer 81

Pterygium Corneal abrasion Normal anterior chamber (for contrast) Shallow anterior chamber Hyphema Hypopyon

Answer 82

- central gray opacity-nucleus cataract - a star shaped opacity - cortical cataract

Answer 83

◦ Optic atrophy (disc pallor) ◦ Papilledema (choked disc) ◦ Excessive cup-disc ratio

Answer 84

◦ Arteriovenous crossing (Nicking) ◦ Narrowed (attenuated) arteries ◦ Diabetic retinopathy (DR) ◦ Moderate nonproliferative ◦ Severe nonproliferative ◦ Proliferative

Answer 85

Test visual acuity ◦ Snellen eye chart Test visual fields ◦ Confrontation test Inspect the EOM function ◦ Corneal light reflex, cover test, diagnostic positions test Inspect external eye structures Inspect anterior eyeball structures Inspect ocular fundus ◦ Optic disc, retinal vessels, general background, and macula

Answer 86

Pupil size also reacts to the amount of ambient light and accommodation or focusing an object on the retina

Answer 87

- the top number is how close you are to the chart - the bottom number is the distance at which a person with normal eyesight would be able to see the same thing (the higher this number the worse it is)

Answer 88

if you see 20/20 you would be seeing the same thing that someone who is 20/40 sees at a different distance

Answer 89

are pupils equal, round, reacting to light, and accomodation

eyes Flashcards

(113 cards)