Problems of the Problems of the EyesEyes

Ma. Tosca Cybil A. Torres, RN, MANMa. Tosca Cybil A. Torres, RN, MAN

Review: Anatomy and Review: Anatomy and PhysiologyPhysiology

The eye is the organ of vision

Parts of the eye

The outer, protective layer

a. Sclera- the protective outer layer of the eye, sometimes referred to as the “white of the eye”. It maintains the shape of the eye

b. Cornea -The front portion of the sclera. It is transparent and allows light to enter the eye. The cornea is a powerful refracting surface, providing much of the eye's focusing power

Choroid- is the second layer of the eye and lies between the sclera and the retina. It contains the blood vessels that provide nourishment to the outer layers of the retina

Ciliary body- anterior continuation of the choroid containing muscles that change the shape of the lens to focus vision

Iris- central extension of the ciliary body, it consists of muscular tissue that responds to surrounding light. The part of the eye that gives it color.

Pupil- defined by the margin of the iris. Constricts and dilates to regulate the amount of light entering the eye’s interior

The middle, vascular layer

The inner, neural layer

Retina-Retina- the innermost layer of the eye. It converts images into the innermost layer of the eye. It converts images into electrical impulses that are sent along the optic nerve to the electrical impulses that are sent along the optic nerve to the brain where the images are interpreted. brain where the images are interpreted.

It is composed of light sensitive cells It is composed of light sensitive cells “photoreceptors”“photoreceptors”• Rod cellsRod cells• Cone cellsCone cells

MaculaMacula -is located in the back of the eye, in the center of the retina. -is located in the back of the eye, in the center of the retina. Within the macula is an area called the Within the macula is an area called the fovea centralisfovea centralis. This area . This area contains the highest concentration of cones, produces the contains the highest concentration of cones, produces the sharpest vision, and is used to see details clearly sharpest vision, and is used to see details clearly

Refractive media

Lens- a transparent, biconvex structure, encased in a thin transparent covering. The function of the lens is to refract and focus incoming light onto the retina for processing

Cornea- transparent layer that forms the external coat of the anterior portion of the eye

Aqueous humor- watery fluid filling the eye’s anterior chamber that serves as refracting medium and maintains the hydrostatic intraocular pressure

Vitreous humor- a jelly-like substance filling the posterior cavity behind the lens, acting as a refractive medium and maintaining the shape of the eye

Assessment:

1. Ocular history a. Elicit a description of the present illness and chief complaintCardinal s/sx include: decrease in visual acuity blurred vision decrease in color perception pain in the eye

b. Explore the client’s health history for risk factors, includes: Family history of eye disease Systemic medical condition Sports injuries Laser surgery Blows to head Vitamin A deficiency Certain medications

2. Visual Acuity

• use of the Snellen chart

3. External eye examination

Assess for the symmetry in the appearnce of the eyes Inspect the eyelid for ptosis, redness, lesions, and

edema Assess the sclera for whiteness Inspect the cornea for transparency, smoothness,

shininess, and brightness Assess for the blink reflex

4. Diagnostic Evaluation

1. Ophthalmoscopy – usually pupil has to be dilated with mydriatic. Changes in the optic nerve head may indicate ICP.

2. Tonometry – accurate measurement of IOP. Normal 10-21 mmHg.

3. Perimetry – for measurement of the boundary of the field of vision. Normal field of vision is 90.

4. Biomicroscope or Slit lamp- an instrument used to examine the anterior segment of the eye under great magnification by means of binocular microscope with a brilliant beam of light for illumination.

4. Diagnostic Evaluation

5. Color Vision Testing (Ishihara Color plate test) – for color blind people to identify the three primary colors

6. CT scan- visualizes the globes, extraocular muscles, and optic nerves

7. Amsler Grid- used to test for macular problems

8. Flourescein Angiography

9. UTZ

Nursing Diagnoses

1. Sensory or perceptual alteration: visual2. Pain 3. Risk for injury 4. Self-care deficit 5. Knowledge deficit 6. Anxiety

Planning and outcome identification

Major goals include the ff:–Prevention of further visual deterioration–Relief of pain –Prevention of injuries – Independence in self care activities –Knowledge of disease process, treatment and

eye care –Control of anxiety

Implementation: Care of the Eyes

– Use of medications – use of drops should be discouraged, tears contain a lysozyme (beta lysine); IgA, Ig G, all inhibit bacterial growth.

– Eye Fatigue – printed matter should be held at least 14 inches from eye; when watching TV, stay 10-12 feet away from the screen.

– Illumination – read in an environment illuminated by bulbs of 100-150 watts; light should come from behind and not reflect a glare.

– Use of dark glasses – it protects the eyes of an individual who change environments by becoming lighter as the individual enters a dark environment and darker as sunlight is entered.

Planning for Health Maintenance and Restoration

Nursing Treatments Instillation of eyedrops – client tilts head

backward and inclined slightly to the site; ask the patient to look up, the nurse pulls down his lower lid and drop the medicine in the center of the lower cul-de-sac or space between the eyeball and inner surface of the lower lid. Allow the medicine to enter the conjunctival sac by capillary attraction. Excess fluid can wiped off and tell the patient to close eyes; do not squeeze for even distribution of the medicine.

Instillation of Eye ointments – same as above. Expel a small amount of ointment from the tip of the tube without coming in contact with the lid; beginning at the inner canthus moving outward to prevent the spread of contaminants into the lacrimal duct.

Glasses:- For adults suggest attractive frames and

encourage proper fitting of glasses.- For children, have glasses changes as

recommended by the ophthalmologist to keep pace with growth changes and shifts in visual acuity

Hot compresses – unless specified use NSS and temperature should be at or slightly above temperature , 46°C-49°C (115°F - 120°F)

Cold compress – to help control bleeding and edema.Eye irrigations – done to remove secretions, to cleanse

the eye preoperatively into supple warmth. NSS are often used because it is more soothing and less likely to cause pain.

Massage of the Eyeball – use in treating glaucoma especially following certain operations.

Contact lensesContact lenses

Types:1. Scleral – fit over the cornea and the

conjunctiva covering the sclera2. Corneal – are tiny disks that are

contoured to fit the anterior cornea.

A Common Ocular Medications

Local anesthetics – act to anesthetize the eye and thus prevent pain during various ocular procedures

1. topical anesthetic – Pontocaine – 0.5%2. Injectable local anesthetics – Novocaine 1-2%; Xylocaine 1-2%

Parasympathomimetic Drugs – produce effects resembling that stimulation of the parasympathetic nerve. Used as miotics which cause pupils to contract and used to control IOP in glaucoma by widening the filtration angle and permitting outflow of aqueous humor.

1. Cholinergic drugs – act directly on the myoneural junction; produce strong contraction of iris and ciliary body musculature (accommodation) (e.g., Pilocarpine HCl 0.5-10%2. Cholinesterase Inhibitors

Parasympatholytic Drugs (anticholinergic drugs) – e.g., those which produce effects resembling those of interruption of parasympathetic nerve supply to a part. Used to facilitate eye exam and refraction. They cause smooth muscles of the ciliary body and iris to relax thus producing mydriasis which causes the pupil to dilate and cytoplegia (paralysis of ciliary muscles, resulting in paralysis of accommodation).

1. mydriatics – Neo – synephrine 2.5 – 10%; eupthaimine 2-5%2. cycloplegics – Atropine sulfate0.5%; Hyoscine 0.25%; Homatropine Hydrobromide 2-5%; Cyclogyl 1-2%; hydriacyl 0.5-1%.

Sympathomimetic Drugs (adrenergic drugs) – used primarily to produce mydriasis and vasoconstriction; do not cause cycloplegia. Vasoconstriction increase outflow of aqueous humor, thus reducing IOP (e.g., Adrenaline 1:1000; Neosynrphrine1.123-10%.

Antibiotics (e.g., Chloromycetin; Neosporin; Polymixin B sulfate; Bacitracin)

Adrenal Corticosteroids – in treatment of nonpyrogenic inflammation and allergic reaction (e.g., Cortison acetate; Prednisone)

Carbonic Anhydrase Inhibitors – an enzyme carbonic anhydrase is one substance necessary for production of aqueous humor. For treatment of glaucoma to reduce formation of aqueous humor and thus reduces IOP. Diuresis is produced (e.g., Oratrol; Diamox)

Common Ophthamic Symbols

– OD – oculus dexter (right eye, RE)– OS – oculus sinister (left eye, LE)– OU – oculus uterque (both eyes)– EOM – extraocular muscles– Gtt (s) – gutta, guttae (drop, drops)– IOP – intraocular pressure

Refractive Errors of the EyesRefractive Errors of the Eyes

Terms/Glossary:

a. Emmetropia – refers to normal eye

b. Refraction – bending of the rays of the light as they pass from one medium to another

c. Accommodation – ability of the eye to adjust from near to far objects

d. Adaptation – ability of the eye to see light from darkness

Common Common refraction refraction errorserrors

Myopia or nearsightedness – usually long anterior –posterior dimensions of the eyeball which causes light rays to focus in front of the retina

Cause: heredity is an important cause; faulty posture; poor nutrition

Signs and symptoms: good vision for near distances

Treatment: use of concave lenses or minus lenses; proper diet

Hyperopia, Hypermetropia or farsightedness – anterior-posterior dimension is too short so that rays focus behind the retina

Cause: principally hereditary

Signs and symptoms: eyestrain or asthenopia; good vision for far distances

Treatment: convex lenses or positive lenses

Common refraction Common refraction errorserrorsPresbyopia or old sight or

farsightedness of the advancing age – affects all person past the age of 45 and is due to gradual loss of accommodation which is due to loss of elasticity of the lens and only partly to weakening of the ciliary muscle

Signs and Symptoms: inability to read without holding the reading material more than 13 feet from the eye.

Treatment: use of bifocal lens

Astigmatism – condition caused by asymmetry or irregular curvature of the cornea so that rays in the horizontal and perpendicular plane do not focus at the same point.

Cause: congenital in nearly all cases of regular astigmatism hereditary is the only known etiologic factor.

Treatment: use of cylindrical lenses. In higher degrees, glasses will be worn at all times; in lower degrees-worn only for occupation causing eyestrain.

Low Vision and BlindnessLow Vision and Blindness

Low vision- best corrected visual acuity (BCVA) 20/70-20/200

Blindness- best corrected visual acuity (BCVA) that can range from 20/400 to no light perception (NLP)

Absolute blindness- absence of light perception

Legal blindness- BCVA not greater than 20/200 in the better eye, widest field diameter is 20 degrees or less

BLINDNESSBLINDNESS

Types:– Congenital blindness – infants born blind– Acquired blindness – individuals who lose

their sight during infancy, childhood, adolescence, adulthood, or during the aging process.

Factors:– Age – onset at which an individual becomes

blind may totally affect the adjustment.– Suddenness of onset- another factor that

may affect adjustments such as traumatic injury or accident

BLINDNESSNursing Care: Support systems Give an ample time to work through their

thoughts, fears and inadequacies Assist for rehabilitation which is the essential

factor. Education

– instruct families about an educational setting, the nurse should encourage them to enroll the child in the kind of educational setting from which he/she can benefit most.

– Resources such as Braille books, talking book tapes, records lectures, and other services are provided for legally blind.

– Rehabilitation: the goal of care is to help each client to lead a normal life as possible.

Guidelines for the Communication Guidelines for the Communication with a Blind Personwith a Blind Person

– Talk in a normal tone voice– Do not try to avoid common phrases in speech

such as “see what I mean”– Touch the person’s hand or arm lightly to

indicate that you are about to speak – Introduce yourself with each contact. If in

hospital, knock on the door before entering.– Explain any activity occurring in the room or

what you will be doing.– Announce when you are leaving the room so

the person is not put into position of talking to someone who is no longer there.

– Be specific when communicating directions. Avoid using phrases such as “over there”.

– Ask the person, “how can I help you?”

Guidelines for Facilitating Independence in ADLs for Blind Persons– Place clothing in specific locations in

drawers and closets.– Place food and cooking utensils in specific

locations in cupboards and/or refrigerator.– Encourage use of cane when walking– Keep furniture and household objects in

specific places.– When assisting a blind person in walking

let person take your arm.– Provide description of foods on the plate

using clock placement of food– Always permit blind persons to pull their

own chair and seat themselves.

The Hospitalized Client

– Client should always be oriented to the environment.

– The nurse should encourage the use of tactile senses by allowing to locate the call light, furniture, windows, bathrooms, and other objects within the environment.

– The client should stand behind nurse who is guiding him, the approach affords an added sense of balance and security.

– The nurse should walk in a straight line.– When leading up and down stairs, the nurse

should pause for a brief moment and then inform the client.

– If handrails are available, the client should be encouraged to use them.

– Doors must never be left partially open, it should always be open or closed.

Visual impairment aids

Aids for the blind1. cane 2. Seeing-eye dog or guide dog

Aids for the partially blind- books and newspapers in large print to enable the

partially blind client to cope with the condition as well as to continue contact with the outside world of pleasure and companionship.

Recreation:1. leisure time activities, special toys should be available

like softball.2. special checkers and checkboards, chess, scrabble and

Braille cards.3. Films, plays and lectures are great sources of

stimulation.4. Young client should be encouraged in physical sports

to relieve aggression and hostility.

GlaucomaGlaucoma– eye disease characterized by increased IOP associated with progressive loss of peripheral vision.

Cause:

obstruction to the circulation of aqueous humor through the meshwork at the angle of the anterior chamber of the eye where the peripheral cornea and iris meet.

Types:Open Angle (Chronic simple or wide)

Glaucoma

Cause: hereditary predisposition to the thickening of the meshwork.– S/sx: – loss of peripheral vision (tunnel vision) before central vision– frequent changes of glasses– difficulty in adjusting to darkness– failure to detect changes in color– tearing, misty vision– Headache– pain behind the eyeball– nausea, vomiting– halos

Open Angle (Chronic simple or wide) Glaucoma – Treatment: Miotics (Pilocarpine) to

constrict the pupil and to draw the smooth muscle of the iris away from the canal of schlem to permit aqueous humor to drain out. Drops are prescribed in early AM since IOP is usually higher on arising in AM.a. Azetazolamide (Diamox) – to reduce

formation of aqueous humor.b. Avoid fatigue or stress.c. Avoid drinking large quantities of fluidsd. Certain limitation are not necessary.

May drink normal amounts of coffee and tea (1-2 cups) and alcoholic beverages

Surgery:

The principle is to improve the drainage of the intraocular fluid or aqueous humor thereby lessening pressure of the eye.

1. Iridencleisis – the opening between anterior chamber and conjunctiva to bypass blocked meshwork and allow aqueous humor to be absorbed into conjunctival tissues. 2. Corneoscleral trephening or Elliot’soperation – small opening is made at the junction of the cornea and sclerae leaving a permanent opening through which aqueous humor may drain.3. Laser trabeculoplasty – creates multiple surface burns to increase outflow ofaqueous humor; treatment of choice if IOP unresponsive to medical regimen.4. Cyclodiathermy or cyclocryotherapy – super-cooled probe or electrical current used to interfere with ability to secrete aqueous humor by ciliary body.

Acute Angle (Close) Glaucoma

Cause: is the result of an abnormal displacement of iris against the angle of the anterior chamber. It is relatively rare disease. Dilation of the pupil caused by darkness, excitement or mydriatic drug may cause blockage of the outflow mechanism eye with a narrowed peripheral angle of the anterior chamber.

Signs and symptoms: severe eye pain, nausea, vomiting and abdominal pain; blurred vision, colored halos around the lights, dilated pupils; increased IOP.

Treatment: miotics (Diamox); osmotic agents such as glycerol also act to reduce the pressure of acute glaucoma.

Surgery: Iridectomy – removal of the portion of the iris.

Absolute glaucoma – is the end result of uncontrolled glaucoma. EnucleationEnucleation is often necessary

General Nursing Care After Glaucoma Surgery

Preop: patient must realize that the vision lost cannot be restored but that further loss can usually be prevented; administer miotics.

Postop:a. position – flat and quiet for 24 hours to prevent prolapse

of the iris through the incisionb. use of narcotics or sedatives to keep patient quiet, and

comfortablec. liquid diet until the first dressingd. turning on his unoperative side.

Long-Term Care:

a. there is usually no restriction on the use of the eyesb. fluid intake generally is not curtailed and exercise is

permittedc. Medical care for the rest of their lives.

Detachment of the Retina – this occurs when:

a. a separation of the two primitive layers of the retina occur because of accumulation of fluid between them.

b. An elevation of both retinal layers away from the choroids occur because of the presence of a tumor

Cause: myopic degeneration, trauma and aphakia (absence of crystalline lens) – most frequent causes.

Detachment of the Retina

Signs and symptoms: floating spots or opacities before the eye due to blood and retinal cells that are freed at the time of the tear and cast shadows on the retina as they seem to drift about the eye; flashes light and progressive constriction of vision in one eye.

Treatment: Conservative: quiet in bed with eyes covered to try to prevent further detachment; head is positioned so that the retinal holes are the lower part of the eye.

Non-surgical methods: employed to seal retinal breaks before retina becomes detached.

photocoagulation – a small burn is made in the retina by shining very bright light through the pupil

cryotherapy- a cold probe is applied to the outer wall of the eye to “freeze” the retina.

Surgical Methods: aimed at sealing the retinal break, reattaching the retina from redetaching (e.g., scleral bucklig)

Postop care:

a. eyes are covered to prevent ocular movementb. position so that the area of detachment is dependentc. pupils are dilated by mydriatic (e.g., Neosynephrine)

and cycloplegic (e.g., Cyclogyl) to facilitate visualization of the retina to decrease movement of the intraocular structures.

Discharge instructions:– avoid strenuous exercises and activity for at least

6 months– contact sports are restricted for the remainder of

the client’s life– avoid sudden jarring or motions of the head– movements of the eyes do not precipitate

recurrence and therefore no restrictions are place on the use of the eyes.

Cataract – opacity of the crystalline lens or of its capsule which interferes with transparency

Signs and symptoms: dimness of visual acuity; rapid and marked changes of refraction error

Classifications:

– Primary or senile- begins first in one eye and then the other eye from 45 years on; it is rare that this becomes unilateral; occurs as degenerative changes with age.

– Secondary or traumatic – due to some disease or injury of the eye (e.g., diabetes); traumatic cataract due to a direct blow or due to exposure to intense light.

– Congenital – not seen at time of birth but when defective vision becomes evident during childhood associated with attack of German measles in the mother during the first trimester of pregnancy.

Treatment:

• Intracapsular extraction – lens is removed within its capsule

• Extracapsular extraction – lens capsule is excise and the lens is expressed by pressure in the eye from below with a metal spoon.

• Phaceoemulsion – requires an incision just large enough to insert a needle probe that vibrate 40,000 times per second to break up the lens and flushed it out in tiny suction unit.

• Enzymatic Zonumolysis – a technique that involves injecting alpha chymotrypsin a fibrinolytic and proteolytic enzyme into the anterior chamber. This enzyme frees the attachment of the lens capsule and thereby facilitate removal of the lens without tearing the lens in the process of removing it.

• Intraocular lens – implantation of a synthetic lens designed for distance vision, the patient wears prescribed glasses for reading and near vision – it is an alternate to sight correction with glasses or contact lenses for the aphasic patient

Nursing CarePreop:• Orient the patient to his new environment.• Begin rehabilitation as soon after admission – DBCE be

taught; instruct how to close eyes without squeezing the lids.• Reduce the conjunctival count – use of antibiotics.• Prepare the affected eye for surgery – instill mydriatics, if

ordered.

Postop

• Reorient patient to his surroundings• Prevent increase in IOP and stress on the suture line

– 1. activities that tend to increase IOP and are therefore restricted during the early postoperative period – coughing, brushing the teeth, shaving, vomiting, bending, stooping.

– 2. bathroom privileges and ambulation are permitted but constipation should be avoided.

• Promote the comfort of the patient – mild analgesicto control pain.• Observe and treat complications:

– 1. nausea and vomiting of anti-emetics drugs and cold compress to the throat.

– 2. hemorrhage – notify physician if patient complains of sudden eye pain.

– 3. prolapse of the iris – most common postop complication and can precipitate acute glaucoma

Promote the rehabilitation of the patient:

1. encourage the patient to become independent – walk with him when he first become ambulatory.

2. Health teachings:

☻ dark glasses maybe prescribed 1-4 weeks after surgery.☻ temporary corrective lenses may be prescribed 6-8 weeks after surgery. The glasses will take the place of the crystalline lens. In six months time, the eye will have made their adjustment. However, the power of accommodation is lost so that a bifocal lens is used.☻ Patient should know that it will take time to learn to judge distances, climb stairs and do other simple things.☻ Color of objects seen with the lens removed is slightly change from and that if they have had the lens removed from one eye to only they will use only one eye at a time but not both together, unless they are fitted with a contact lens with the operated eye.☻ ambulatory patient should have slip-on slippers to avoid bending or stooping.☻ peripheral vision is decreased, so that the patient needs to be taught to turn his head and utilize the central vision provided by the lenses

COMMON RELATED DISORDERS

Injuries and Trauma – in general when an injury is present it is advisable to treat the client but leave the eye alone. The exception to this rule is when a chemical injury has occurred and the eye itself must be immediately flushed with water. When removing foreign particles, do not touch the cornea. Irrigation is done for at least 15 minutes before stopping to move the patient or get a doctor. If water is not available, use beer and carbonated beverages.

Hordeolum or stye – infection of the Zels gland in the follicle of a lash

Chalazion – involves a melbomian gland located in the tarsal plate of the lid. Treatment: I&D and antibacterial ointment.

Conjunctivitis – can be caused by a wide variety of bacteria; often called “pink eye”. May result from bacterial infection,

allergy, trauma as in sunburn and viruses.

Uveitis – inflammation of the iris in combination with inflammation of the ciliary body and choroids.

Keratitis – inflammation of the cornea.

Pterygium – a triangular fold of membrane which forms in the conjunctiva which extends from the white of the eye

to the cornea.