Chapter 16 - Assessing Eyes

POAG Risk Factors

-Increased Intraocular pressure above 21 mmHg -African American, Mexican American, Asian American ethicnity -Advancing age -Family history of glaucoma -Diabetes -Hypothyroidism -Eye injuries, tumors, inflammatory processes -Prolonged corticosteriod use -nearsightedness

Risk Factors of Cataracts

-Increasing age -Exposure to ultraviolet B light -Diabetes mellitus -Cigarette smoking -Alcohol use -Diet low in antioxidant vitamins -High blood pressure -Eye injuries/surgery -Steroid use -Female gender -Persistent diarrhea -Gout -Abdominal obesity -Beta blocker use

Causes of Glaucoma

-eye injury -inflammation -tumor -advanced cataracts -diabetes may also be an unknown cause

Cataracts

-leading cause of blindness -clouding of the usually clear lens of the eye, causing a person to see as though looking through a frosty or foggy window.

myopia

-nearsightedness, impaired far vision -second number on acuity result is larger than the first ex 20/40

Normal Eye Pressure

10 - 21 millimeters of mercury

Ophthalmoscope

An instrument used to look inside the eye

anisocoria

An unequal size of the pupils (less than 0.5 mm difference) is normal, greater in dim light compared to bright light, Causes: trauma, tonic pupil and oculomotor nerve paralysis.

Corneal light reflex

Assesses parallel alignment of the eyes. Reflection of light on corneas should be in the exact same spot. Irregularities: may be due to muscle weakness or paralysis.

Sudden Vision changes

Changes associated with head trauma or increased intracranial pressure

Gradual Vision changes

Changes that may be related to aging, diabetes, hypertension, or neurologic disorders

E Chart

Chart used by children and non English speaking patients. Scored same as snellan

Spots or floaters

Common among clients with myopia or in clients over 40

sclera

Dark-skinned clients may have _______ with yellow or pigmented freckles.

presbyopia

Farsightedness, impaired near vision, occurs when client must move the client further than 14" -caused by decreased accommodation -common in clients over 45 years of age

retina

Inner lining of the eye that receives the images formed by the lens and transmits those images to the brain through the optic nerve. Contains rods and cones, specialized nerve cells that are responsive to light

oculus sinister

Left Eye: pupillary reaction in fraction form Ex. 3/2 Top number indicates size of pupil at rest Bottom number indicates the constricted size

pupillary light reflex

Normal constriction of the pupils when bright light shines on the retina

Lutein and zeaxanthin

Nutrients that reduce the risk of chronic eye diseases including macular degeneration and cataracts Foods: Kale, spinach, collards, turnip greens, corn, green peas, broccoli, romaine lettuce, green beans, eggs, and oranges

oculus dexter

Right Eye: pupillary reaction in fraction form Ex. 3/2 Top number indicates size of pupil at rest Bottom number indicates the constricted size

consensual pupil response test

Test pupillary reaction to light: while client looks straight ahead, approach each eye from the client's side with a penlight. Observe the pupillary reaction in the opposite eye.

direct pupil response test

Test pupillary reaction to light: while client looks straight ahead, approach each eye from the client's side with a penlight. Observe the pupillary reaction.

optic chiasma

The cross-shape where some of the information from the left and right eye crosses over to pass into the opposite side of the brain.

21mm, 2 mm

The eyes of African Americans protrude slightly more than those of Caucasians, and African Americans of both sexes may have eyes protruding beyond ____. A difference of more than _____ between two eyes is abnormal.

Acute angle-closure glaucoma (AACG)

Type of Glaucoma: Signs and Symptoms: -severe eye or eyebrow pain -severe headache -nausea and vomigting -sudden onset of visual disturbance, often in low light -blurred vision -rainbow halos around the lights -reddening of the eye

Cover Test

Use opaque card to cover an eye to observe for eye movement. Eyes should remain fixed and should not have to move to reestablish focus

pinguecula

Yellowish nodules on the bulbar conjunctiva. These harmless nodules are common in older clients and appear first on the medial side of the iris and then on the lateral side.

Optic nerve discs

____________are larger in Blacks, Asians, and Native Americans than in Hispanics and non-Hispanic whites.

Cyanosis

__________of the lower lid suggests heart or lung disorder

Scotoma

a blind spot that is surrounded by either normal or diminished peripheral vision.

iris

a circular disc of muscle containing pigments that determine eye color

Glaucoma

a group of eye conditions resulting in optic nerve damage usually caused by abnormally high intraocular pressure. -Second leading cause of blindness.

episcleritis

a local, noninfectious inflammation of the sclera. The condition is usually characterized by either a nodular appearance or by redness with dilated vessels.

arcus senilis

a normal condition in older clients, appears as a white arc around the limbus. The condition has no effect on vision.

eye orbit

a round, bony hollow formed by several different bones of the skull

caruncle

a small, fleshy mass that contains sebaceous glands

Optic atrophy

a white-colored disc without vessels and is seen with the death of the optic nerves.

Jaeger Test

acuity test for near vision, holds newspaper 14 inches away

Ectropion

an everted lower results in exposure and drying of the conjunctiva. Interferes with normal tear drainage.

Entropion

an inverted lower lid, may cause pain and injure the cornea as eyelashes brushes against the conjunctiva and cornea. Interferes with normal tear drainage.

Nystagmus

an oscillating (shaking) movement of the eye - may be associated with an inner ear disorder, multiple sclerosis, brain lesions or narcotics use.

Positions Test

assesses eye muscle strength and cranial nerve function / extraocular movements. Eye movement should be smooth and symmetric

lens

biconvex, transparent, avascular, encapsulated structure located immediately posterior to the iris

Intermittent blind spots

blind spot associated with vascular spasms or pressure on the optic nerve by a tumor or intracranial pressure

Consistent blind spots

blind spots that may indicate retinal detachment

trigeminal nerve

carries the afferent sensation into the brain, supports the corneal reflex

facial nerve

carries the efferent message that stimulates the blink

Glaucoma

causes enlarged physiologic cup

pupil

central aperture of the iris

Snellen Chart

chart used for testing distance vision; contains letters of varying size and is administered from a distance of 20 feet; a person who can read at 20 feet, what the average person can read at this distance is said to have 20/20 vision

lacrimal apparatus

consists of glands and ducts that lubricate the eye

ciliary body

consists of muscle tissue that controls the thickness of the lens, which must be adapted to focus on objects near and far away

Strabismus

constant malalignment of the eyes

direct reflex

constriction occurs in the eye exposed to light

bulbar conjunctiva

covers most of the anterior eye

optic disc

cream-colored, circular are located on the retina, where the optic nerve enters the eyeball.

Vitamin C

decrease the risk of cataracts and reduce the risk of age-related macular degeneration

sclera

dense, protective, white covering that physically supports the internal structures of the eye.

diplopia

double vision, may indicated increased intracranial pressure due to injury or a tumor

ptosis

drooping of the upper lid Seen with: oculomotor nerve damage, myasgthenia gravis, weakened muscle or tissue or a congenital disorder.

Epiphora

excessive tearing caused by exposure to irratants or obstruction of the lacrimal apparatus.

indirect or consensual light

exposure to the light in one eye results in constriction of the pupil in the opposite eye

accommodation

functional reflex allowing the eyes to focus on near objects

Conjunctivitis

generalized redness of the conjunctiva "pink eye"

chalazion

inflammation of meibomian glands may produce extreme swelling of the lid

medial canthus

inner point that joins eyelids; contains puncta and caruncle

esotropia

inward turn of the eye

palpebral conjunctiva

lines the inside of the eyelids

lacrimal gland

located in the upper outer corner of the orbital cavity, produced tears

Macular degeneration

major cause of visual impairment that affects the macula portion of the retina

Primary Open-Angle Glaucoma (POAG)

most prevalent type of glaucoma Signs and symptoms: -gradual loss of peripheral vision, usually in both eyes -tunnel vision in the advanced stages

Oblique Muscles

muscles responsible for diagonal movement

Rectus Muscles

muscles responsible for straight movement.

visual perception

occurs as light rays strike the retina, where they are transformed into nerve impulses, conducted to the brain through the optic nerve, and interpreted

exotropia

outward turn of the eye

Eyelashes

projections of stiff hair curving outward along the margins of the eyelids that filter dust and dirt from air entering the eye.

Vitamin E

protect cells of the eyes from damage caused by unstable molecules. Foods: Nuts, fortified cereals, and sweet potatoes

exophthalmos

protrusion of the eyeballs accompanied by retracted eyelid margins -characteristic of Graves' disease

visual field

refers to what a person sees with one eye

meibomian glands

secrete an oily substance that lubricates the eyelid

Halos

seen around lights, associated with narrow-angle glaucoma

extraocular muscles

six muscles attached to the outer surface of each eyeball that control six different directions of eye movement.

Rods

specialized nerve cells, regulated black and white vision

Cones

specialized nerve cells, regulated color vision

hordeolum

stye or inflammation of glands in lid

Papilledema

swelling of the optic disc, appears as a swollen disc with blurred margins, seen with hypertension or increased intracranial pressure -visible and numerous disc vessels -lack of visible physiologic cup

lacrimal canals

tears empty into the __________________

limbus

the point where the sclera meets the cornea

conjunctiva

thin, transparent, continuous, membrane that is divided into two portions: a palpebral and a bulbar portion.

corneal reflex

touch cornea with cotton wisp produces blinking or tearing

cornea

transparent layer, permits the entrance of light, which passes through the to retina.

Night blindness

trouble seeing at night, associated with optic atrophy, glaucoma and Vitamin A deficiency

eyelids

two movable structures composed of skin and two types of muscle: striated and smooth. Purpose is to protect eye from foreign bodies and limit the amount of light entering the eye.

puncta

two small openings that allow drainage of tears into the lacrimal system

Phoria

used to describe misalignment that occurs only when fusion reflex is blocked.

Amsler Test

used to evaluate visual field defects

Tonometry

used to measure pressure within the eye

blepharitis

waxy, white scales (seborrheic) or inflammation of hair follicles (Staphylococcus aureus) causes local redness, swelling or pain

palpebral fissure

white space between open eyelids

Acuity Result

written like: 20/20 First number indicates the distance from the chart Second number refers to the last line that could be read.