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1Elsevier items and derived items © 2007 by Saunders, an imprint of Elsevier, Inc.
Chapter 51
Eye and Vision Disorders
2Elsevier items and derived items © 2007 by Saunders, an imprint of Elsevier, Inc.
Figure 51-1
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Figure 51-2
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Figure 51-3
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Visual Pathway• Light enters eye, passes through transparent cornea, aqueous
humor, lens, and vitreous humor • These structures are called refractive media • Refract (bend) horizontal and vertical light rays so that the light rays
focus on the retina • On retina, light rays are reversed and upside down • Images carried as impulses through the optic nerve • At optic chiasm, fibers from the left field from each eye join to form
the left optic tract • Fibers from right field of eye join to form right optic tract • Images transmitted to the brain by way of the optic tracts
6Elsevier items and derived items © 2007 by Saunders, an imprint of Elsevier, Inc.
Figure 51-4
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Age-Related Changes in the Eye• Skin around the eye becomes wrinkled and loose • Eyelids usually have some excess tissue; not important unless it
interferes with vision • The amount of fat around the eye decreases, permitting the
eyeball to sink deeper into the orbit • Tear secretion diminishes; cornea less sensitive • Grayish ring may be around the outer margin of the iris• Pupil smaller and responds more slowly to light • Presbyopia: ability to focus is impaired
8Elsevier items and derived items © 2007 by Saunders, an imprint of Elsevier, Inc.
Health History
• History of present illness • Record changes in vision• If pain, inquire about location and nature• Sensitivity to light (photophobia) • Discharge from the eyes• Complaints that the eyes feel dry and irritated
• Past medical history • Diabetes, neurologic disorders, thyroid disease,
hypertension
9Elsevier items and derived items © 2007 by Saunders, an imprint of Elsevier, Inc.
Health History
• Family history • Any eye diseases as well as a history of
arteriosclerosis, diabetes, and thyroid disease • Functional assessment
• Patient’s occupation, roles, usual activities
10Elsevier items and derived items © 2007 by Saunders, an imprint of Elsevier, Inc.
Physical Examination• Inspect the external
eye, assess response of the pupil to light, and evaluate gross visual acuity
• If abnormalities suspected, inform physician or advise patient to seek medical evaluation
• Acuity commonly tested with Snellen chart
11Elsevier items and derived items © 2007 by Saunders, an imprint of Elsevier, Inc.
Diagnostic Tests and Procedures
• Ophthalmoscopic examination• Refractometry• Visual fields• Tonometry• Fluorescein angiography • Corneal staining• Imaging procedures
• CT, ultrasonography, radioisotope scanning, or MRI
12Elsevier items and derived items © 2007 by Saunders, an imprint of Elsevier, Inc.
Therapeutic Measures
• Eye irrigation• Topical medications
• Miotics• Mydriatics• Anesthetics• Cycloplegics• Antibiotics• Anti-inflammatory drugs
• Eye surgery• Surgical incisions, lasers, and cryotherapy
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Preoperative Nursing Care
• Assessment• Patient’s emotional state, ability to perform self-
care, and knowledge of surgical routines and outcomes
• Be sure the patient understands the preoperative routine
• Interventions• Anxiety • Self-Care Deficit
14Elsevier items and derived items © 2007 by Saunders, an imprint of Elsevier, Inc.
Postoperative Nursing Care
• Assessment• Vital signs and level of consciousness • Inspect dressing for bleeding or drainage • Patient comfort, including pain and nausea • If vision impaired, inspect environment for safety
hazards • Before discharge, determine patient’s understanding
of and ability to administer prescribed medications by having the patient demonstrate self-medication
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Postoperative Nursing Care
• Interventions• Risk for Injury • Disturbed Sensory Perception • Acute Pain • Anxiety • Ineffective Therapeutic Regimen Management
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Protection of the Eyes and Vision
• Patient teaching• Adults younger than 40 years of age should have
their eyes examined every 3 to 5 years • After the age of 40, examinations every 2 years and
should include testing for glaucoma • When there are symptoms of eye problems, patients
should seek medical advice
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Protection of the Eyes and Vision
• Prevention of injuries• Teach young children the danger of throwing or
poking objects at the faces of playmates • Assess toys for safety • Adult activities that produce sparks or cause
fragments to be dispersed also cause injuries • Advise protective eyewear for such potentially
dangerous activities
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Protection of the Eyes and Vision
• Basic eye care • Gently cleanse the eyelids each time the face is
washed; use a clean cloth without soap • Wash eye from the inner canthus (near the nose)
toward the outer canthus
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Effect of Visual Impairment
• Mild losses may require only some adaptations • Serious losses affect independence, mobility,
employment, and interpersonal relationships • People grieve for the lost function just as they might
grieve after the death of a loved one • Factors that affect a person’s response to this loss
include personality, usual coping style, effect of vision loss on the person’s life, and the circumstances of the loss
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Care of the Visually Impaired Patient
• Be aware of visually impaired person’s thoughts and feelings about handicaps
• Assume that people with visual impairments can be independent and productive
• The person needs help with some tasks but should be treated as an adult
• The extent of vision loss determines the types of assistance needed
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Care of the Visually Impaired Patient
• Interventions• Disturbed Sensory Perception • Ineffective Coping • Self-Care Deficit • Ineffective Therapeutic Regimen Management
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Blepharitis
• Inflammation of hair follicles along eyelid margin • Caused by bacteria, most often by staphylococci • Symptoms include itching, burning, and photophobia;
scales or crusts on the lid margins• Physician may prescribe an antibiotic ointment • Be certain that any medication applied to the eye is an
ophthalmic preparation • Eyelids can be gently cleansed with baby shampoo
solution
23Elsevier items and derived items © 2007 by Saunders, an imprint of Elsevier, Inc.
Hordeolum
• Commonly called a stye • Common acute staphylococcal infection of the eyelid
margin that originates in a lash follicle• Affected area of lid is red, swollen, and tender • Apply warm, moist compresses several times a day• Repeated infections may be related to staphylococcal
infections at some other location on the body • Physician may treat with ophthalmic antibiotics
24Elsevier items and derived items © 2007 by Saunders, an imprint of Elsevier, Inc.
Chalazion
• Inflammation of the glands in the eyelids • Swelling prevents fluid from leaving the glands,
causing tenderness • Warm compresses may bring some relief • Physician may order antibiotics if infection • Surgical removal of the gland necessary if
condition persists
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Conjunctivitis
• Inflammation of the conjunctiva caused by microorganisms, allergy, or chemical irritants
• Bacterial conjunctivitis commonly called pinkeye • Red conjunctiva, mild irritation, drainage • Warm/cool compresses, topical vasoconstrictors• Infected people should practice good hand washing
and should avoid sharing washcloths
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Conjunctivitis
• Viral conjunctivitis caused by herpes simplex virus type 1, herpes zoster virus, or adenoviruses • Characterized by redness and drainage • Round, raised white or gray areas on the
conjunctiva • Infections caused by herpes simplex virus type 1
are treated with ointments or other topical medications
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Keratitis
• Inflammation or infection, or both, of the cornea • From bacteria, viruses, fungi; chemical or mechanical
injuries cause inflammation that may be followed by infection
• No noticeable drainage, but considerable pain • Topical antibiotics and topical corticosteroids • Systemic antibiotics after culture and sensitivity • Sometimes physician injects antibiotics directly into the
conjunctiva
28Elsevier items and derived items © 2007 by Saunders, an imprint of Elsevier, Inc.
Entropion
• The lower lid turns inward • Eyelashes rub against the eye, causing pain
and possibly scratching the cornea • Surgical correction usually recommended
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Ectropion
• The lower lid droops and turns outward • The eye does not close completely, causing it
to become dry and irritated • The dry cornea is easily injured • Requires surgical correction
30Elsevier items and derived items © 2007 by Saunders, an imprint of Elsevier, Inc.
Foreign Body
• Blinking/tearing wash small irritants from eye • If foreign body remains, evert the upper and lower lids • If object is clearly visible and does not appear to be
embedded, you may attempt to remove it • Use sterile cotton swab to touch object gently • If object not embedded, it usually clings to swab and
can be removed • If object is embedded, it should be removed only by a
physician
31Elsevier items and derived items © 2007 by Saunders, an imprint of Elsevier, Inc.
Corneal Opacity
• Inflammation and infection• When cornea injured by infection or trauma, scar tissue may
form • If scar tissue prevents light from entering the eye, varying
degrees of vision impairment occur • Only treatment is keratoplasty (removal of the scarred cornea
and replacement with a healthy cornea) • During keratoplasty, damaged cornea removed first
• An identically sized graft then taken from the donor eye and secured to the recipient’s eye with very fine suture
32Elsevier items and derived items © 2007 by Saunders, an imprint of Elsevier, Inc.
Care of the Patient Having Keratoplasty
• After surgery, the keratoplasty patient has an eye pad and a metal shield over the operative eye
• Corticosteroid eye drops may be ordered to reduce inflammation
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Care of the Patient Having Keratoplasty
• Assessment• Inspect dressing for drainage and ask if patient has pain or
nausea • After dressing is removed, inspect for corneal opacity• Also evaluate the patient’s visual acuity
• Interventions• Risk for Injury • Pain • Impaired Sensory Perception • Ineffective Therapeutic Regimen Management
34Elsevier items and derived items © 2007 by Saunders, an imprint of Elsevier, Inc.
Myopia
• The medical term for nearsightedness • The lens is situated too far from the retina • Light rays come together to focus in front of the
retina • People with myopia have difficulty seeing
distant images clearly • New glasses needed approximately every 2
years
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Hyperopia
• Commonly known as farsightedness• The lens is too close to the retina• Light rays come together behind the retina • The hyperopic person sees clearly in the
distance but has difficulty focusing on close objects
• Convex corrective lenses needed
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Figure 51-16
37Elsevier items and derived items © 2007 by Saunders, an imprint of Elsevier, Inc.
Astigmatism
• Irregularities in the cornea or lens• If condition is mild, the natural lens can correct
for the abnormality • If severe, vision is distorted, and corrective
lenses are needed
38Elsevier items and derived items © 2007 by Saunders, an imprint of Elsevier, Inc.
Presbyopia
• Poor accommodation due to loss of elasticity of the ciliary muscles • Accommodation: adjustment of the lens for near and
distant vision• Contraction or relaxation of the ciliary muscles,
which causes the lens to change shape • It most often develops after age 40 years • Corrective lenses are needed
39Elsevier items and derived items © 2007 by Saunders, an imprint of Elsevier, Inc.
Medical Treatment
• Corrective lenses for errors of refraction • Eyeglasses • Contact lenses
• Surgical treatment • Photorefractive keratectomy (PRK) • Laser in situ keratomileusis (LASIK)
• Nursing care• Encourage periodic examinations and know if the
patient uses corrective lenses
40Elsevier items and derived items © 2007 by Saunders, an imprint of Elsevier, Inc.
Cataract
• Lens opaque (cloudy); no longer transparent• Causes: congenital, traumatic, degenerative • Pathophysiology
• Injuries cause opacity rapidly, whereas age-related opacity progresses slowly
• Signs and symptoms: cloudy vision, seeing spots or ghost images, and floaters
• Medical treatment • Cataract extraction
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Figure 51-17
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Cataract
• Complications • Leakage of vitreous humor, hemorrhage into the
eye, and opening of the incision • Lens replacement
• Cataract eyeglasses • Contact lenses • Intraocular lenses
43Elsevier items and derived items © 2007 by Saunders, an imprint of Elsevier, Inc.
Care of the Patient with Cataracts
• Preoperative care• Drops used before cataract surgery are mydriatics,
cycloplegics, antibiotics, and nonsteroidal anti-inflammatory agents
44Elsevier items and derived items © 2007 by Saunders, an imprint of Elsevier, Inc.
Care of the Patient with Cataracts
• Postoperative care• Assessment
• Pain and nausea • Patient is likely to wear a patch and shield over operative
eye • Note any drainage • Also note level of consciousness and orientation
• Interventions• Risk for Injury • Impaired Sensory Perception
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Glaucoma
• Pathophysiology • Intraocular pressure is above normal • Caused by interference with outflow of aqueous
humor • Although glaucoma may follow trauma, exact cause
is often unknown • Peripheral vision is lost first • Field of vision gradually narrows until tunnel vision • Complete blindness eventually occurs
46Elsevier items and derived items © 2007 by Saunders, an imprint of Elsevier, Inc.
Types of Glaucoma
• Open-angle glaucoma • Prevents the normal passage of aqueous humor through the
trabecular meshwork • Usually there are no signs and symptoms at first • Tired eyes, blurred vision, and halos around lights • Need for frequent changes in eyeglass prescriptions• Treated first with drug therapy
• Beta-adrenergic blockers, adrenergics, cholinergics, carbonic anhydrase inhibitors, and hyperosmotic agents
• Surgical procedures: trabeculoplasty, trabeculectomy, and cyclocryotherapy
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Glaucoma
• Angle-closure glaucoma• Flow of aqueous humor through the pupil is blocked • Pressure forces iris forward; blocks trabecular meshwork • Rapid rise in intraocular pressure; if not lowered promptly,
permanent blindness can result • Signs and symptoms: sudden, acute pain; blurred vision, halos
around lights, nausea and vomiting, and headache on the affected side
• Drugs for treatment: miotics and oral or intravenous carbonic anhydrase inhibitors
• After pressure lowered, iridotomy or iridectomy usually recommended to prevent recurrence
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Glaucoma
• Assessment• Collect data about patient knowledge of the disease
and treatment and patient ability to carry out self-care
• Interventions• Risk for Injury • Fear and Ineffective Therapeutic Regimen
Management • Pain
49Elsevier items and derived items © 2007 by Saunders, an imprint of Elsevier, Inc.
Retinal Detachment
• Pathophysiology • Separation of sensory layer from pigmented layer
• Begins when a tear in the retina allows fluid to collect between the sensory and the pigmented layers
• The fluid causes the two layers to separate • Separation deprives sensory layers of nutrients and oxygen that
normally are supplied by the blood vessels in the choroid • Leads to damage to the nerve tissue in the sensory layer and
resultant partial or complete loss of vision • Retinal tears may occur spontaneously or as a result of
trauma
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Retinal Detachment
• Signs and symptoms • Depend on location and extent of detachment • Patients report seeing light flashes or floaters • Vision may be cloudy • If area of detachment is large, vision may be lost
completely • Some patients say it seems as if a curtain has come
down or across the line of vision
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Retinal Detachment
• Medical and surgical treatment • Laser photocoagulation • Cryotherapy • Scleral buckling
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Retinal Detachment
• Nursing care• Before corrective measures, the patient usually is placed on
strict bed rest with the head elevated • Postoperative care essentially the same as for other patients
undergoing eye surgery• Positioning orders may be specific for these patients • Surgeon prescribes activity limitations; length of hospitalization
depends on location and severity of the tear, the type of repair, and the surgeon’s routines
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Senile Macular Degeneration• Changes in the eye cause the macula to degenerate • Both eyes usually affected • Two types
• Dry (strophic)• Abnormal blood vessels develop in or near the macula resulting in
loss of vision in a specific area • Wet (exudative)
• Central vision gets gradually worse• Special telescopic lenses may be helpful • Laser treatments may offer hope to some patients• Nurse needs to help the patient and family members learn to cope
with declining vision
54Elsevier items and derived items © 2007 by Saunders, an imprint of Elsevier, Inc.
Enucleation
• Removal of the eye• From injury, infection, sympathetic ophthalmia, and
some glaucomas and malignancies • Postoperative observe for excessive bleeding or
increasing pain • Report any temperature elevation • After pressure dressing removed, physician may order wound
care and topical medications • Approximately 1 month after the enucleation, a prosthesis can
be fitted by an optician