Chapter 14 Eyes Notes PDF

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Jarvis Physical Examination & Health Assessment Chapter 14 Eyes Regis University Loretto Heights School of Nursing UNIT OBJECTIVES: Upon completion of this unit the student will be prepared to:  Identify the anatomical features and functions of the eye.  Identify the structures viewed through the ophthalmoscope.  Define pupillary light reflex, fixation, and accommodation.  Identify age-related changes in the eye.  Demonstrate appropriate gathering of subjective data of the eyes.  Demonstrate general techniques of assessment of the eyes.  Incorporate health promotion concepts and screenings when performing eye assessment.  Correctly identify variations in health in the assessment of the eyes.  Demonstrate documentation of subjective and objective data of the eyes. Eyes  Eye is the sensory organ of vision  Neocortex is a thin layered structure surrounding the brain. It is the hallmark of mammalian brains not present in birds or in reptiles. Called "neo" because it is evolutionarily the newest part of the cerebral cortex  More than half of the neocortex is involved with processing visual information Anatomical Structure and FunctionExternal Anatomy  Eyes are well-protected by: o Eyelids o Palpebral fissure o Limbus o Canthus o Caruncle o Tarsal plates o Meibomian glands o Conjunctiva  Palpebrallines eyelids  Bulbar- overlays eyeball o Lacrimal apparatus

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Extraocular muscles: o Superior rectus o Lateral rectus o Inferior rectus o Medial rectus o Inferior oblique o Superior oblique o Movement of extraoccular musldes is stimulated by three cranial nerves  CN 6- Abducens: lateral rectus  CN 4- Trochlear: superior oblique  CN 3- Oculomotor: all other directions, and…  Controls raising of upper eyelid  Controls parasympathetic fibers to lens and pupil o Constricting iris controlling lens shape

Internal Anatomy  Outer Layer o Sclera & Cornea  Middle Layer o Choroid o Pupil o Lens o Ciliary body controls thickness of lens  Inner Layer o Retina-visual receptor o Optic disc o Macula o Retinal vessels

Visual Pathways and Visual Fields  Refraction of light rays on the Retina  The image formed on the retina is upside down and reversed from its actual appearance in the outside world. The light rays are refracted through the transparent media of the eye before striking the retina, and the nerve impulses are conducted through the optic nerve tract to the visual cortex of the occipital lobe of the brain. The left side of the brain interprets vision for the right eye.  Crossing of fibers at optic chiasm o Temporal & Nasal o Results in upside down, reversed images Visual Reflexes  Pupillary light reflex- normal constriction of pupils in response to light  Fixation o Puts object in center of visual field  Accommodation o Adaption of the eye for near vision o Eyes should converge and constrict as object gets closer Subjective Data- Heath History  Vision difficulty: decreased acuity, blurring… o Floaters are a common sensation with myopia or after middle age and are attributable to condensed vitreous fibers. Floaters or spots are not usually significant, but the acute onset of floaters may occur with retinal detachment. o Scotoma-blind spot o Photophobia-light sensitivity  Pain- differentiate between optical and nasal  Strabismus-cross eyed, diplopia-double vision, nystagmus-shaking/twitching  Redness, swelling  Watering or excessive discharge  History of ocular problems including injury, surgery, allergies  Glaucoma- family history, testing  Use of glasses or contact lenses o How often do you get prescription checked o What is cleaning regiment for contacts  Environment/psychological issues w/ vision changes, color vision, etc.  Additional history for infants and children o Any vaginal infection at delivery?  Chlamydia causes blindness in babies eyes, herpes and gonorrhea can impact o Parents note any childhood milestone deficits with vision?  Squinting, etc. o Any routine eye exams at school? o Are parents aware of safety measures to protect eyes from trauma? Toys inspected? o Have parents taught safety of sharp objects (carrying/playing w scissors, pencils, etc.)?  Additional history for aging adult o Have you noticed any visual difficulty with climbing stairs or driving? o Any problem with night vision? o When was last time tested for glaucoma?

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o Any aching pain around eyes? Any loss of peripheral vision? o If you have glaucoma, how do you manage your eyedrops? o Is there history of cataracts? o Any loss or progressive blurring of vision? o Do your eyes ever feel dry or burning? What do you do for this? o Any decrease in usual activities, such as reading or sewing? Sample Charting: Vision reported good with no recent change. No eye pain, no inflammation, no discharge, no lesions. Wears corrective lenses, vision last tested 1 year PTA, test for glaucoma at that time was normal.

The Exam  Preparation o Position and lighting  Equipment needed o Snellen eye chart & Handheld visual screener o Opaque card or occluder o Penlight o Applicator stick o Ophthalmoscope Objective Data- KNOW THESE TESTS 1. Test central visual acuity o Snellen alphabet chart is most common and accurate measure of visual acuity (there are variations) o If the person is unable to see even the largest letters when standing 20 feet from the chart, then the nurse should shorten the distance to the chart until the letters are seen, and record that distance (e.g., "10/200"). If visual acuity is even lower, then the nurse should assess whether the person can count fingers when they are spread in front of the eyes or can distinguish light perception from a penlight. If vision is poorer than 20/30, then a referral to an ophthalmologist or optometrist is necessary, but the nurse must first assess the visual acuity.  Result is what patient can see at 20 feet vs what is normal to see at x feet  Myopia- nearsighted. Light focuses in front of retina, causes distance objects to blur. Most common eye problem  Hyperopia- farsighted.  Astigmatism- unevenly curved cornea causes blurred vision o If visual acuity even lower, assess whether person can count your fingers when they are spread in front of eyes or distinguish light perception from your penlight o Test near vision  For those who report increasing difficulty reading and over 40  Test near vision with handheld vision screener with various sizes of print, e.g., a Jaeger card  Presbyopia- age related inability to see close up and reduced night vision 2. Test visual fields o Confrontation test gross measure of peripheral vision; compares person’s peripheral vision with yours  *You have to have good peripheral vision to assess someone else  Have patient cover one eye while you cover opposite eye, stand 2 feet apart, bring fingers into view from periphery in several directions and have them say “now” when they see them. You should see them at same time.

 Normal is about 50° upward, 90° temporally, 70° inferiorly, 60° nasally  Abnormal suggests peripheral vision loss, stroke, glaucoma 3. Inspect extraocular muscle function o Corneal light reflex (Hirschberg test)- should see reflection of light ring at same spot on each eye when shining light toward eyes as they look straight ahead  Asymmetry indicates deviation in alignment from muscle weakness or paralysis.  Strabismus- eyes do not properly align; wandering eye o Esotropia- eye(s) turn inward, can cause diplopia  Diplopia- double vision o Exotropia- eye(s) turn outward o Hypertropia- eye turned upward o Hypotropia- eye turned downward o Cover test- extraocular muscle. Resting eye should not move when uncovered o Esophoria- nasal drift of eye when uncovered o Exophoria- temporal drift of eye when uncovered o Diagnostic positions test- lead eyes through six cardinal positions of gaze. Eyes should track at the same time i.e. parallel movement  Nonparallel eye movement indicates muscle weakness or nerve damage  Nystagmus- fine, oscillating movement of eye o Normal at extreme lateral gaze, otherwise abnormal o Other Abnormal Findings include Paralysis 4. Inspect external ocular structures o General: begin with external points, work inward o Eyebrows- present and symmetrical o Eyelids and lashes- present, fully close o Watch for dermatitis o Eyeballs- note any exophthalmos or enophthalmos o Conjunctiva and sclera- not any swelling, lesions, etc o Scleral icterus is yellowing of sclera indicating jaundice o Presence of small brown macules on the sclera are normal in dark-skinned people o Lacrimal apparatus o No swelling, redness, or drainage from the puncta should be observed when it is pressed. Regurgitation of fluid from the puncta, when pressed, indicates duct blockage. The lacrimal glands are not functional at birth. 5. Inspect anterior eyeball structures o Cornea and lens- shine light from side to check smoothness and clarity o The outer layer of the eye is very sensitive to touch. o Arcus senilis is normal in aging adult o Iris and pupil: o Should be flat with round regular shape and even coloration, 3-5mm o Pupillary light reflex (direct and consensual)- darken room and ask person to gaze into distance to dilate pupils. Advance light from side.  Direct light reflex- pupil should constrict when light shines on it  Consensual light reflex- opposite pupil should constrict simultaneously  Presence of shadows across iris may indicate glaucoma. o Accommodation test- ask person to gaze into distance to dilate pupils, then have them shift gaze to object held about 8cm (3in) from their nose. Normal response is pupillary constriction and convergence of axes of the eyes.

o Documentation for Normal Pupils: PERRLA KNOW THIS o Pupils o Equal o Round o Reactive to o Light and o Accommodation 6. Inspect ocular fundus o Use of the ophthalmoscope to enlarge view of eye, darkened room to dilate o Red reflex- red glow in pupil when about 10” away, caused by reflection of ophthalmoscope light on inner retina o Media should be clear of shadows or black dots o Inspect optic disc, retinal vessels, general background and macula o Optic disc is located on nasal side of retina and should be creamy yelloworange to pink with distinct edges. o Normal variation of disc margins are scleral crescent or pigment crescent o Retinal Vessels have: number, color, A:V ratio, caliber, A-V crossing, tortuosity, and pulsations Sample Charting:  Snellen chart – O.D. 20/20, O.S. 20/20 -1. Fields normal by confrontation. Corneal light reflex symmetric bilaterally. Diagnostic positions test shows EOMs intact. Brows and lashes present. No ptosis. Conjunctiva clear. Sclera white. No lesions. PERRLA.  Fundi- Red reflex present bilaterally. Discs flat with sharp margins. Vessels present in all quadrants without crossing defects. Retinal background has even color with no hemorrhages or exudates. Macula has even color. Developmental Competence Infants and Children-Visual acuity  Neonates: test light perception-should blink, pupils also constrict to light source.  Newborn-function limited, peripheral vision intact, EOM poorly coordinated, macular vision (keenest) absent.  Birth-2 weeks: refuse to open eyes after light exposure, may fixate on object.  2-4 weeks: fixates on object.  1 month: fixate and follow light/bright toy.  3-4 months: binocularity established, able to fixate, follow, and reach for toy.  Macula mature by 8 months old.  6-10 months: fixate/follow toy in all directions.  3-6 y/o: Picture chart or Snellen E chart.  7-8 y/o: standard Snellen alphabet chart.  Eyeball reached adult size by 8 y/o.  80% neonates born farsighted & improves by age 8 y/o.  Visual fields: 3 y/o or > when cooperative.  Color vision: Boys only 4-8 y/o.  EOM for strabismus-must catch before 6 y/o otherwise prognosis is poor.  External eye structures: epicanthal folds, Brushfield’s spots, hypertelorism (Down Syndrome). Developmental Competence Aging adult  Visual acuity o Perform same examination as described in adult section o Pupil size decreases with age

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o Presbyopia: “older vision” The lens loses elasticity and decreases its ability to change shape to accommodate for near vision. o Central acuity may decrease due to macular degeneration, particularly after 70 years of age; peripheral vision may be diminished. Macular degeneration is the most common cause of blindness. It is characterized by the loss of central vision. o Cataracts a clouding of the lens in the eye, which leads to a decrease in vision. Ocular structures o Eyebrows may show loss of outer one third to one half of hair because of decrease in hair follicles; remaining brow hair is coarse o As 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 o Eyes may appear sunken from atrophy of orbital fat; orbital fat may herniate, causing bulging at lower lids and inner third of upper lids o Lacrimal apparatus may decrease tear production, causing eyes to look dry and lusterless and person to report a burning sensation o Pingueculae commonly show on sclera  Yellowish elevated nodules are due to thickening of bulbar conjunctiva from prolonged exposure to sun, wind, and dust; appear at 3 and 9 o’clock positions o Cornea may look cloudy with age o Arcus senilis commonly seen around cornea  Gray-white arc or circle around limbus due to deposition of lipid material  As more lipid accumulates, cornea may look thickened and raised, but arcus has no effect on vision o Xanthelasma: soft, raised yellow plaques occurring on lids at inner canthus  Commonly occur around fifth decade and more frequently in women, occur with both high and normal levels of cholesterol, and have no pathologic significance o Pupils become smaller in old age; pupillary light reflex may be slowed o Lens loses transparency and looks opaque Ocular fundus o Retinal structures generally have less shine; blood vessels look paler, narrower, and attenuated; arterioles appear paler and straighter, with a narrower light reflex o Drusen: benign degenerative hyaline deposits  A normal development on retinal surface  Often symmetrically placed without pattern in eyes- no effect on vision

Structure and FunctionCultural Competence  Palpebral fissures are typically narrower in persons of Asian origin o Also feature of Down’s syndrome  Culturally based variability exists in color of iris and retinal pigmentation o Darker irises often have darker retinas behind them  Racial variations in disease: o Primary open-angle glaucoma affects African Americans  3-6X > whites and is 6X more likely to cause blindness than in whites; reasons are not known o Percent of adults age 18 and over reporting visual limitations and trouble seeing with glasses in 2003 was highest, 16.7%, among American Indians and Alaska Natives, and African Americans, 10.4%; and whites 9.5%.  Poverty is also an extenuating factor; 26.4% of population living in poverty report this problem o Blindness has racial and ethnic variations-

In whites > 40 years, leading cause of blindness is age-related macular degeneration (54%), followed by cataracts (9%)  In African Americans > 40 years, cataracts and open-angle glaucoma together cause 60% of blindness  In Hispanics > 40 years, leading cause of blindness is open-angle glaucoma 

Abnormal Findings Abnormalities in the Eyelids (p. 313 Table 14.2)  Preorbital edema- swollen and puffy lids. Occurs with crying, CHF, renal failure, allergies, hypothyroidism  Exophthalmos- protruding, bulging eyes o Graves disease-hyperthyroidism  Enophthalmos- sunken eyes o Caused by loss of fat in orbits, associated with dehydration, and chronic wasting; elderly  Ptosis- drooping upper lid due to neuromuscular weakness, cranial nerve III damage, sympathetic nerve damage (Horner’s), congenital  Upward palpebral slant- can be normal, but indicator of Down Syndrome in combination with other indicators  Ectropion-lower lid is loose and rolling out, does not approximate to eyeball. Excessive tearing and dry, itching eyes result. Occurs in older adults and is attributable to atrophy of the elastic and fibrous tissues. The lower lid does not approximate to the eyeball, and, as a result, the puncta cannot effectively siphon tears; excessive tearing results.  Entropion- lower lid rolls in due to spasms of lids or scar tissue contraction. May irritate eye. Abnormal Findings- Lesions on the Eyelids (p. 315, Table 14.3)  Blepharitis- inflammation of eyelids, Symptoms include red, irritated, itchy eyelids, along with the formation of dandruff-like scales at the base of the eyelashes and the eyelids.  Chalazion-infection or cyst in sebacious gland  Hordeolum (Stye)- infected hair follicle, usually with Staph  Dacryocystitis- inflammation of lacrimal sac (tear duct)  Basal cell carcinoma- most often on lower lid; small painless nodule with ulceration. Abnormal Findings- Abnormalities in the Pupil  Anisocoria- unequal pupil size. Normal in 5% of population. CNS disease indicator.  Monocular blindness- when light directed at blind eye, neither eye responds; when light directed at seeing eye, both eyes constrict  Miosis- Constricted and fixed pupils. Possible causes include narcotics, brain damage  Mydriasis- dilated and fixed pupils. Stimulation of sympathetic nervous system usually by trauma or drugs.  Argyll Robertson pupil- no reaction to light, small and irregular bilaterally. Occurs with CNS syphilis, brain tumor, meningitis, chronic alcoholism.  Tonic pupil, (Adie’s pupil)- reaction to light and accommodation is sluggish. Usually unilateral. No pathological significance  Cranial nerve III damage- unilateral dilated pupil that has no reaction to light or accommodation and occurs with nerve damage. Ptosis may be present.  Horner’s syndrome- a unilateral, small, regular pupil that reacts to light and accommodation. Due to lesion of sympathetic nerve. Miosis, ptosis, anhidrosis also present. Usually reversible. Abnormal Findings- Vascular Disorders of External Eye (p. 319, Table 14.6)  Conjunctivitis- “pink eye”, red, beefy vessels at periphery. Purulent discharge if infected. o Allergic conjunctivitis- itching, redness, watering, discomfort, swelling.

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Iritis (circumcorneal redness)- deep, dull red halo around iris and cornea along with marked photophobia, constricted pupil, blurred vision. Subconjunctival hemorrhage-blood in sclera from trauma. Primary Angle Closure Glaucoma/ Acute Glaucoma- circumcorneal redness around iris with dilated pupil. Pupil is oval and dilated. Cornea appears “steamy. Symptoms include sudden clouding of vision, pain, and halos of light. Open Angle Glaucoma- Open-angle glaucoma is the most common type of glaucoma; virtually no symptoms are exhibited. Vision loss begins with the peripheral vision, which often goes unnoticed because individuals learn to compensate intuitively by turning their heads.

Abnormal Findings- Vascular Disorders of The Cornea and Iris (p. 320, Table 14.7)  Pterygium- opaque wing of bulbar conjunctiva that overgrows to center of cornea.  Corneal Abrasion- blunt eye injury that scratches cornea. A corneal abrasion causes irregular ridges in reflected light, which produce a shattered appearance to light rays. No opacities should be observed in the cornea.  Shallow Anterior Chamber- due to pressure  Hyphema- blood in the anterior chamber and is a serious result of blunt trauma (a fist or a baseball) or spontaneous hemorrhage and may indicate scleral rupture or major intraocular trauma. May also result from herpes zoster.  Hypopyon- purulent matter in anterior chamber that occurs with iritis and inflammation Abnormal Findings- Lens Opacities (p. 322, Table 14.8)  Central Gray Opacity- nuclear cataract characteristic  Star Shaped Opacity- Cortical Cataract shows as asymmetric, radial, white spokes with black center. Abnormal Findings- Optic Disc Abnormalities (p. 322, Table 14.9)  Optic Atrophy (Disc Pallor)- white or gray disc as result of partial or complete death of optic nerve  Papilledema (Choked Disc)- a serious sign of increased intracranial pressure, which is caused by a space-occupying mass s...