Eyes Flashcards
Measuring visual acuity
Near
Far
Peripheral vision
Inspect eyebrows for
hair texture
size
extension
Inspect orbital area for
edema
redundant tissue or edema
lesions
Inspect eyelids for
ability to open and close completely eyelash position ptosis fasculations or tremors flakiness redness swelling and palpate for nodules
Pull down lower lids to inspect the following
palpebral conjunctiva - coats inside of eyelids
bulbar conjunctiva - covers outer surface and protects anterior surface of the eye
and sclerae
inspect for color, discharge, lacrimal gland punctum and pterygium
Inspect external eyes for
corneal clarity corneal sensitivity corneal arcus color of irides pupillary size and shape pupillary response to light and accomodation, afferent pupillary defect, swinging flashlight test Nystagmus
Palpation of lacrimal gland and evaluating muscle balance and movement
palpate the lacrimal gland in the superior temporal orbital rim
evaluate eye movement with corneal light reflex
cover-uncover test
six cardinal fields of gaze
Opthalmoscopic examination
lens clarity red reflex retinal colors and lesions charactersistics of blood vessels disc characteristics macula characteristics depth of anterior chamber
A&P of the eye
transmits visual stimulation to brain
occupies orbital Occupies orbital cavity/anterior aspect exposed
Direct embryologic extension of the brain
Attached by four rectus muscles/two oblique muscles
Innervated by cranial nerves III, IV, and VI
Connected to brain by cranial nerve II
External Eye
Composed of five structures
Eyelid - distributes tears, limits light and protects from foreign bodies
Conjunctiva
Lacrimal gland - produces tears, drains in canaliculi
Eye muscles - superior,inferior,medial and lateral rectus
Bony skull orbit
Function of eyelids
Distribute tears over eye surface
Limit amount of light entering the eye
Protect the eye from foreign bodies
Function of conjunctiva
Protects the eye from foreign bodies and desiccation
Lacrimal gland
Produces tears that moisten the eye
Eye Muscles
Each eye is moved by six muscles.
Superior, inferior, medial, and lateral rectus muscles
Superior and inferior oblique muscles
They are innervated by cranial nerves III (oculomotor), IV (trochlear), and VI (abducens).
Ocular motor nerve
Levator palpebrae superioris (which elevates and retracts the upper eyelid)
All extraocular muscles except for the superior oblique muscle and the lateral rectus muscle
Trochlear nerve
superior oblique is innervated
abducens nerve.
lateral rectus muscle is the only muscle innervated
Three layers of the inner eye
Outer fibrous layer Sclera posteriorly and cornea anteriorly Middle layer - uvea Choroid posteriorly and ciliary body/iris anteriorly Inner layer Retina
Structures of the inner eye
Sclera Cornea Iris Lens Retina
Sclera
White of the eye
Avascular
Supports internal eye structures
Cornea
Continuous with the sclera anteriorly
Clear
Sensory innervation for pain
Major part of the refractive power of the eye
Uvea
Iris, ciliary body, and choroids comprise the uveal tract.
Iris
is a circular, contractile muscular disk containing pigment cells that produce the color of the eye.
Dilates/contracts to control amount of light traveling through the pupil to the retina
Ciliary body
produces the aqueous humor and contains the muscles controlling accommodation.
Choroid
pigmented, richly vascular layer that supplies oxygen to the outer layer of the retina.
Lens
biconvex, transparent structure located immediately behind the iris
Supported circumferentially by fibers arising from the ciliary body
Contraction or relaxation of the ciliary body changes its thickness.
Changes in lens thickness allow images from varied distances to be focused on the retina
Retina
Transforms light impulses into electrical impulses, which are transmitted through:
Optic nerve
Optic tract
Optic radiation
Visual cortex
Consciousness in the cerebral cortex
Binocular vision is achieved when an image is fused on the retina by the cornea and the lens
Major landmarks of the retina
Optic disc, from which the optic nerve originates, together with the central retinal artery and vein
Macula, or fovea, is the site of central vision.
Infants and Children
Eye forms during first 8 weeks of gestation
Can be malformed d/t maternal drug ingestion
Lacrimal drainage complete at birth
2 to 3 weeks - lacrimal gland produces full volume of tears
Infants and children cont
Term infants hyperopic [20/400]
Peripheral vision fully developed at birth
Central vision develops later
By 3 to 4 months of age, binocular vision development is complete.
By 6 months, vision has developed sufficiently so that the infant can differentiate colors.
The globe of the eye grows as the child’s head and brain grow, and adult visual acuity is achieved at about 4 years of age.
Older Adults
The major physiologic eye change that occurs with aging is a progressive weakening of accommodation (focusing power) known as presbyopia.
Loss of lens clarity and cataract formation
Older Adults
The major physiologic eye change that occurs with aging is a progressive weakening of accommodation (focusing power) known as presbyopia.
Loss of lens clarity and cataract formation
HPI: Red eye
Red eye (presence of conjunctival redness)
Difficulty with vision - one or both eyes corrected by lenses
Recent injury of foreign body; sleeping in contact lenses
Pain- with or without vision loss, in or around the eye, superficial or deep, insi
History of eye surgery
History of resent illness or similar symptoms in the household
Allergies - seasonal, associated symptoms
Secretions - clear or yellow, consistency (purulent or watery) duration, tears that run down face, decreased tear formation c sensation of gritty eyes
Medications - eye drops, antibiotics, artificial tears, glaucoma meds, steroids
PMHx
Trauma Eye surgery-laser vision correction, date and outcome Chronic illness that can affect vision Hypertension/atherosclerotic cardiovascular disease (ASCVD) Diabetes mellitus Glaucoma Inflammatory bowel disease Thyroid dysfunction Autoimmune diseases HIV
FH
Retinoblastoma (retinal cancer)
Often an autosomal dominant disorder
Glaucoma, macular degeneration, diabetes, hypertension, or others that may impact vision or eye hea
Color blindness, cataract formation, retinal detachment, retinitis pigmentosa, or allergies affecting the eye
Nearsightedness, farsightedness, strabismus, or amblyopia
Personal and Social
Employment exposure
Activities
Use of protective devices during work or activities that might endanger the eye
Corrective lenses
History of cigarette smoking (a risk factor for cataract, glaucoma, macular degeneration, thyroid eye disease)
HPI in infants and children
Preterm
Symptoms of congenital abnormalities including failure of infant to gaze at mother’s face or other objects; failure of infant to blink when bright lights or threatening movements are directed at the face
Strabismus some or all of the time
HPI in young children
Excessive rubbing of the eyes, frequent hordeola, inability to reach for and pick up small objects, night vision difficulties
HPI in school-aged children
Necessity of sitting near the front of the classroom to see the board; poor progress in school not explained by intellectual ability
Hx of pregnant women
Presence of disorders that can cause ocular complications such as pregnancy-induced hypertension (PIH) or diabetes
Symptoms indicative of PIH
Diplopia, scotomata, blurred vision, or amaurosis
Use of topical eye medications that may cross placenta
Hx in older adults
Visual acuity
Decrease in central vision, distortion of central vision, use of dim or bright light to increase visual acuity, complaints of glare, difficulty in performing near work without lenses
Excess tearing
Dry eyes
Development of scleral brown spots
Nocturnal eye pain
Sign of subacute angle closure and a symptom of glaucoma
Equipment
Snellen eye chart Rosenbaum/Jaeger near vision card Penlight Cotton wisp Ophthalmoscope Eye cover, gauze, or opaque card
Visual testing
Use Snellen chart.
Each eye tested individually
Test with and without corrective lenses.
If vision less than 20/20, conduct pinhole test.
This maneuver permits light to enter only the central portion of the lens.
Should result in an improvement in visual acuity by at least one line on the chart if refractive error is responsible for the diminished acuity
Test without glasses first
Near vision test
Use Rosenbaum pocket screener.
Each eye tested individually
Peripheral vision test
Estimate with confrontation test.
Accurate measurement requires instrumentation.
Color vision test
Rarely tested in the routine physical examination
External examination of surrounding structures
Inspect eyebrows for size, extension, and hair texture.
Inspect orbital area for edema, puffiness, and sagging tissue below orbit.
Coarse eyebrowns and do not extend beyond temporal canthus may be hypothyroidism
Periorbital edema is associated c thyroid eye dx, allergies, renal disease
Yellow-tinted lesions on periorbital tissue represent lipid deposits (xanthelasma),
Eyelid inspection
Inspect closed lid for fasciculations and tremors.
Check ability to close completely/open widely.
Observe margin for flakiness, redness, and swelling.
Look for eyelashes.
Note eye opening.
Ptosis - congenital or acquired weakness. Record difference of two eyelids in mm
Note any eversion or inversion of lids. Lower lid turned away is ectropion d/t excessive tearing
Lid eyelashes may cause conjunctival irritation increasing risk of infection in those c entropion
Stye usually caused by staphylococcal infection
Eyelid palpation
Palpate for nodules.
Palpate the eye itself through closed lids.
Digital palpation tonometry - involved eye might be much harder than uninvolved eye
Pain - scleritis, orbital cellulitis, and cavernous sinus thrombosis
Firm eye that resists palpation may indicate severe glaucoma
Conjunctivae inspection
Usually inapparent, clear, and free of erythema
Inspect lower portion by pulling down lower lid.
Upper lid is inspected only if foreign body is in the eye.
Look for redness/exudate.
Look for pterygium.
Abnormal growth of conjunctiva that extends over the cornea from the limbus
Observe conjunctiva for erythema or exudate - conjunctivitis
Bright red blood indicates sub-conjunctival hemorrhage
Blood stays red d/t diffusion of oxygen through conjunctiva
Pterygium - abnormal growth of cobjunctiva over corneum. Seen more on nasal side
Cornea inspection
Examine clarity of the cornea by shining light on it.
Cornea is normally avascular; blood vessels should not be present.
Test sensitivity (cranial nerve V) by touching the cornea with a cotton wisp to elicit blink (cranial nerve VII). Decreased sensitivity is associated c diabetes, herpes simplex, and herpes zoster
Inspect for corneal arcus (arcus senilis).
Composed of lipids deposited in the periphery of the cornea
Subtle clear area between limbus and the arcus
Arcus seen in 60 or older
Lipid disorder if before 40
Iris and pupil inspection
Inspect iris for pattern, color, and shape. - round, regular and equal in size
Test for direct/consensual light response.
Test pupils for accommodation.
The pupils should constrict when the eyes focus on the near object.
Estimate pupil size and compare for equality.
Lens inspection
Inspect for transparency/clarity
Sclera
Examine to ensure that it is white.
Inspect for senile hyaline plaque.
Liver dx may make sclera yellow or green
Lacrimal apparatus
Inspect lacrimal gland.
Palpate lower orbital rim near inner canthus.
Extraocular Eye movements
Test eye movements using six cardinal fields of gaze.
Check for nystagmus.
Note lid lag.
Note exposure of sclera above iris.
Use corneal light reflex to test extraocular muscle balance.
If imbalanced, perform cover-uncover test.
Opthamoscopic examination
Inspection of interior eye with ophthalmoscope permits visualization of: Optic disc Arteries Veins Retina Adequate pupil dilation is necessary.
Visualize red reflex
Visualize red reflex. Opacities appear as black densities. Examine Fundus Vascular supply Disc margins Macula
Unexpected findings
Look for unexpected findings such as: Myelinated nerve fibers Papilledema Glaucomatous cupping Drusen bodies Cotton wool bodies Hemorrhages
Examination in infants
Note symmetry, muscle balance, and presence of red light reflex.
Inspect lids for swelling and epicanthal folds.
Inspect lid level covering eye.
Note eye spacing.
Inspect sclera, conjunctiva, pupil, and iris.
Testing cranial nerves in infants
Test cranial nerves.
Vision: observe object preference/focus/tracking.
Optical blink: note closure and head response to bright light.
Corneal reflex: same as adult
Funduscopic examination deferred until infant is 2 to 6 months old (unless visual problems).
Red reflex should be elicited in all newborns.
Examination in children
External structure inspection same as for infant
Visual acuity tested with Snellen E game at 3 years of age.
Visual acuity tested in younger children by observing activities
Peripheral vision tested in cooperative child
Cranial nerve tests same as for adult
Funduscopy requires patience.
Examination in pregnant
Retinal examination helps differentiate between chronic hypertension and pregnancy-induced hypertension (PIH).
Vascular tortuosity, angiosclerosis, hemorrhage, and exudates may be seen in patients with a long-standing history of hypertension
PIH changes include segmental arteriolar narrowing with a wet, glistening appearance indicative of edema.
Cycloplegic and mydriatic agents should be avoided unless retinal disease is suspected.
Systemic absorption
Abnormalities in extraocular muscles
Strabismus: Both eyes do not focus on an object simultaneously.
Visual field defects
Defective vision or blindness in a single eye
Risk factors for cataract formation
FH of cataracts Steroid medication use Exposure to UV light Cigarette smoking DM Aging
HPI: Vision Problem
Eyelids: recurrent hordeola (stye; acute infection of sebaceous gland), chalazion (chronic blockage of meibomian gland), ptosis (drooping) of the lids so they interfere with vision, growth or masses, itching
Involves one or both eyes, corrected by lenses, involving near or distant vision, primarily central or peripheral, transient or sustained
Cataracts (uni or bilateral), types (diabetic, traumatic, surgical)
Adequacy of color vision
Presence of halos around lights, floaters, diplopia (one eye covered or both eyes open)
Trauma to the eye as a whole or structure, events surrounding the trauma; efforts at correction
Snellen Chart
Determine smallest line pt can identify
When testing second eye, have pt read right to left to prevent recall
Numerator indicates distance pt is from chart
Denominator indicates what average eye can read
Smaller the fraction the worse the vision
20/200 is legal blindness
Pinhole test
performed if acuity is less than 20/20
Blurred vs double
Blurred - problem c visual acuity
Diplopia - perception of two images that may be monocular or binocular
Monocular is optical problem
Binocular is alignment problem
Factors affecting visual acuity
motivation and interest, literacy, intelligence, and attention span
Rosenbaum pocket vision screener
Have pt hold card 14 inches from eyes and read smallest line to test near vision
Confrontation test
Peripheral vision
stand opposite of pt at a distance of 3 feet
Ask pt to cover right and you cover left
Tell pt to look at your eye and you look at theirs
have pt tell you when fingers can be seen
Compare how long it take you vs the pt
Test nasal, temporal, superior and inferior
Lesions from CVA, retinal detachment, optic neuropathy, pituitary tumor compression, and central retinal vascular occlusion may cause abnormality
Not significant test otherwise
Color vision test
Rarely used
red testing helpful in determining subtle optic nerve, even when visual acuity is normal
Blepharitis
crusting along eyelash
d/t bacterial infection, seborrhea, psoriasis, rosacea or allergic response
Lagophthalmos
note whether eyelids meet completely when pts eyes are closed
cornea becomes dry and increased risk of infection
Thyroid eye dx, Bell palsy, overaggressive ptosis or bepharoplasty are common causes
Miosis
Pupillary constriction less than 2mm in diameter
Morphine ingestion
Mydriasis
Pupillary dilation more than 6mm in diameter
Coma (diabetes, alcohol, uremia, epilepsy, brain trauma)
Failure to respond (fixed) c light stiumulus
yep
Agryll Robertson pupil
Irregularly shaped pupils that fail to constrict c light but retain constriction with convergence
Not equal in size
Swinging flashlight test
Evaluate optic nerve
shine light in one eye and then rapidly swing to other
Abnormal if pupil continues to dilate instead of constrict
Pupil constriction d/t accomodation
Ask pt to loook at a distant object and then at a test object (pencil or finger) held 10cm from bridge of nose
Pupils should constrict when eyes focus on near object
Anisocoria
Unequal size of pupils
Usually congenital
Adie Pupil
Pupil is dilated and reacts slowly or fails to react to light
CN VI
Lateral rectus
CN IV
Superior oblique
Nystagmus
Eye moves rapidly to the right and then slowly drifts leftward = nystagmus to the right
Full movements indicate integrity of muscle strength and cranial nerves
Lid lag
Exposure of sclera above the iris when pt follows your finger from ceiling to floor may indicate thyroid dx
Corneal light reflex
Balance of ocular muscles
Ask pt to look at object, not light source
Light should be reflected symmetrically
Cover-uncover tset
Cover one eye and observe uncovered eye for movement as it focuses on designated point.
Uncover eye and watch for movement
View for strabismus
Look for exotropic or esotropic
