Unit 4 - Eyes Flashcards
What is the outer fibrous layer of the internal eye
Sclera posteriorly and cornea anteriorly
What is the middle layer of the eye
Choroid posteriorly and ciliary body/iris anteriorly
What is the inner layer of the internal eye
The retina
What are the 5 major structurs of the internal eye
Slcera, cornea, iris, lens, retina
Is the sclera vacular?
No it is avascular
What is the scleras purpose
Supports internal eye structures
Cornea is continuuous with the ____ anteriorly
Sclera
What part of the internal eye is the sensory innervation for pain
The cornea
What is the major part of the refractive power of the eye
The cornea
What do the iris, ciliary body, and choroids comprise
The uveal tract
What produces aqueous humore and contains the muscles controlling accomodation
The ciliary body
What of the internal eye is a pigmented, richly vascular layer that supplies oxygen to the outer layer of the retina
The choroid
Where is the lens located
Immediately behind the iris
How is the lens supported
Circumferentially by fibers arising from the ciliary body
What changes the thickness of the lens
Contraction/relaxation of the ciliary body
What is the sensory network of the eye
The retina
How does the retina work
Transforms light impulses into electrical impulses
What part of the brain interprets impulses as visual objects from the retina
The cortex
When does the eye form
During first 8 weeks of gestation - can be malformed due to drug ingestion/infection
When is lacrimal drainage complete
At birth
When does the lacrimal gland begin to produce full volume of tears
By 2-3 weeks
______ depends on nervous system maturation and occurs over time
Vision development
What is term infants vision like
Hyperopic [20/400]
When is peripheral vision fully developed compared to central vison
At birth, central develops later
When is binocular vision development complete
By 3-4 months
When is vision developed sufficiently so that the infant can differentiate colors
By 6 months
The glob of the eye grow as the childs ____ grow
Head an brain
Adult visual acuity is acheived by what age
4 years of age
What changes are common in pregnant womens eye
Hypersensitivity and changes in refractory power
Tears in a pregnant woman can contain an increased level of ____ resuting in what
Lysozyme; results in greasy sensation and perhaps blurred vision for contact lens wearers
Where does edema and thickening occur in pregnant women
Corneal
What type of retinopathy can happen in pregnant women
Diabetic retinopathy
What type of pressure falls in pregnant womens eyes
Intraocular pressure
What can occur/resolve spontaneously in pregnant women
Subconjunctival hemorrhages
What is the major physiologic eye change that occurs with aging
Progressive weakening of accomodation (focusing power) known as presbyopia
Loss of lens ____ and ___ formation can happen in older adults
Clarity; cataract
What visual exam detects and defines important neurological or ocular disease
Visual field testing
When is the visual acuity exam recorded
Beginning of eye exam
What visual exam gives valuable clinical info about disease or their processes
Pupillary exam
What is the order of visual examination
Visual acuity, visual field testing, pupillary exam, ophthalmoscopy
What color should the conjunctiva of the eye be
Should be pink at the lid margins
What is the acronym PERRLA for
The pupil of the eye, pupils are equal, round, reactive to light and accomodation
What does the pinhole occluder test for
Visual acuity improvement
What is standard for near vision testing
Rosenbaum near vision card
What is the test for color vision
Ishihara
What motion does the superior oblique do
Medial and downward movement
What motion does the inferior oblique perform
Medial and upward
What is innervated by the trochlear nerve
The superior oblique
What is innervated by the abducens nerve
The lateral recuts
What can you find with peripheral field tests that were previously undetected
Occipital strokes and optic chiasmal tumors (pituitary or suprasellar masses)
What light reflex causes the pupil to constrict with light stimulus
Direct light reflex
What light reflex causes opposite/contralateral pupil to consrict with light stimulus
Indirect/consensual light reflex
What light reflex shows light reflected in both pupils equally
Corneal light reflex
What is a normal variant characterized by a physiological difference in muscular tone between right and left pupils but doesnt change with illumination
Physiological anisocoria
What happens when the pupil of an affected eye is smaller (miotic); patient has ipsilateral ptosis and anhidrosis;difference varies with illumination
Horners syndrome
What abnormal pupil rsponse constricts only response to accomodation but not in response to light
Argyl robertson
What abnormal pupil response is seen in tertiary syphillis, diabetics, alcoholics neoplasm, infx, and is ALWAYS pathological
Argyll robertson
What abnormal pupil response is a. Tonic pupil that fails to constrict in response to both light and accomodation eventually may constrict but is sluggish and is ALWAYS benign
Adies pupil
What is an afferent pupillary defect also called
Marcus gunn pupill
What is marcus gunn pupil
Has normal efferent system, but abnormal afferent pathway,
What is the mc cause of marcus gunn pupil
Optic neuritis, also assymmetric optic neuropathy
What are causes of optic neuritis
Demyelinating diseases, infx, sinus infx, drugs, radiation therapy
What is a cobalt aperature filter for
To evaluate small lesions, corneal abrasions, foreign bodies
What is a red free filter aperature used for
Highlights hemorrhages
What pathology has an opaque gray ring at the periphery of the cornea just within sclerocorneal junction
Arcus cornealis
Who frequently gets arcus cornealis
Elderly
What causes arcus cornealis
From fatty granules in or hyaline degeneration of lamellae and cells of cornea
What is another name for a hordeolum
A stye
What is an inflammation of the lash follicle
Hordeolum
What pathology has a plugged meibomian gland
Chalazion
How do you tell the difference between the hordeolum and chalazion
Hordeolum is painful, chalazion is non tender
What pathology has inflammation of eyelids, hard to manage due to recurrence and what are the 2 types
Blepharitis (anterior = outer lid bacteria) (posterior = inner lid caused by oil or meibomian)
What pathology has a yellowish flat plaque that occurs near inner canthus of eyelid mc on upper lid and can be soft or semi hard, frequently symmetrical
Xanthelasma
How many xanthelasma occur with elevated plasma levels
50%
What can cause xanthelasma
High plasma lipid levels, altered lipoprotien composition
Who frequently gets xanthelasma
Frequently occur in patients with type 2 hyperlipidemia
What pathology is a wedge shaped growth lateral to the iris that can cover iris
Pterygium
What are two abnormal growths on the surface of the eyes
Pinguecula and pterygium
Where are cases of pterygum and pinguecula usually seen im the world
Warm dry climates
What is cats eye called
Coloboma
What is a white reflex that indicates something is changing the normal color of the retina (decreased BS) or that something is obstructing the normal reflex
Leukocoria
What causes leukocoria
Mc congenital cataract
What is the most serious cause of the leukocoria
Retinoblastoma
What pathology is a condition that affects normal use of the eyes and visual development
Amblyopia
What are 3 major causes of amblyopia
Strabismus, unequal focus, cloudiness of the eye tissues
What is the mc cause of blindness in individuals under the age of 65
Diabetic retinopathy
What is the risk factor for diabetic retinopathy
Duration of the diabetes, 90% in those with the disease more than 15 years
What is the most common form of diabetic retinopathy
Nonproliferative diabetic retinopathy
Who is more common to get NDR
Type 1 diabetes = 100%, type 2 = 60%
What pathology is characterized by growth of new vessels on the surface of the retina
Proliferative diabetic retinopathy
What pathology has progressive loss of vision, fine-severe loops of new vessels growing in optic disc, leak causeing retinal edema
Proliferative diabetic retinapathy
What pathology has small yellowish areas of coloration in the retina and occur due to swelling of surface of retina (microinfarcts)
Cotton wool spots
What are the mc causes of cotton wool spots
Diabetes and high bp
What is often the earliest recognizable clinical sign of diabetic retinopathy
Microaneurysms
What pathology has small round dark red dots on the retinal surface that are less than the diameter of the optic veins
Microaneurysms
What happens to microaneurysms as the degree of retinal involvement progresses
They increase in number
What pathology resembles bundles of straw and may be round/flame shaped
Hemorrhages
What indicates an increasingly ischemic retina
Hemorrhages
As the number of _____ increase the retinal vessels become more damaged and leaky, leading to exudation of fluid, lipid, and proteins
Hemorrhages
What pathology has bright reflective white or cream colored lesions on the retina
Exudates
What do exudates on the retina indicate
Vessel permeability and increased risk of retinal edema
If exudate swelling occurs on macula what hapens
Vision may be lost
Who is more likely to have hypertensive retinopathy
AA patients with only hypertensive retinopathy that is asymptomatic
All the findings of hypertensive retinopathy stem from hypertension induced changes in what
Retinal microvasculature
Hypertension leadss to lying down of what in the tunica intima of mediaum and large arteries
Cholesterol
Hypertensive retinopathy leads to decreassd lumen size of vessels and focal closure giving rise to what
Hemorrhages and cotton also related to increase in ICP
What is the normal arteriovenous ratio
3;5 to 2;3
The site of crossinng the arteriole and vein share a common what
Adventitial sheath
What causes a compression of the underlying lumen resulting in AV nicking or a tapering of a venule
Vascular sclerosis
What is the most common reason for AV nicking
Prolonged systemic hypertension
What are round yellow deposits that form within a layer under the retina that cause vision to be effected when forming in the macula
Drusen bodies
The increased pressure of glaucoma leads to what
Destruction of optic nerve fibers and visual field deficits
Ophthalmological exam of glaucoma reveals what
Cupping of the optic disk
What is common when there is traction on the retina by viterous gel
Retinal tears
What is posterior vitrous detachment
With aging vitreous humor detaches from the retina and can cause floaters in the eye
What layers are associated with retinal dettachement
Sensory and pigmented layers
Retinal detachment is considered an _____ because it can cause permanent visual damage
Ocular emergency
What type of retinal detachment is common in nearsightend that have undergone eye surgery or have experience serious eye injury
Sensory layers and fluid seeps underneath the retina
What is the 2nd most commmon type of retinal detachment
When strands of vitreous or scar tissue create traction on retina
Patients with diabetes are more likley to experience whatt type of retinal detachement
2nd kind where scar tissue creates traction
Whatt is the 3rd type of retinal detachment
Fluid collects underneath layers causing separation
How are 1st and 3rd retinal detach different
1st involves sensory layer breaking
What retinal detachment occurs in conjunction with another disease that affects the eyes
3rd
What symptoms have light flashes, wavy/watery vision, shower of floaters, sudden decrease in vision
Retinal detachment
What is an optic disc swelling secondary to eleveated ICP
Papilledema
Papilledema is almost always present as a ______ phenomenon and may develop over hours to weeks
Bilateral
The disk swelling of papilledema is result of what
Axoplasmic flow stasis with intra axonal edema in optic disc
How much larger is the pan optic ophthalmascope than traditional
Pan optic = 25, 5 degrees is traditional
The panoptic has a larger field of view and therefore what shows five times larger
The fundus is five times larger
What is used for detecting strabismus
Strabismoscope
Photoscreening is used to detect what
Amblyopia (lazy eye) and strabismus is children
What else is photoscreening used for other than amblyopia and stabismus
Obtain images of pupillary reflexes and red reflexes
The snellen chart is used for a screening examination of ___ vision
Far vision
Visual acuity is recorded as a what
Fraction with numerator of 20
The larger the denominator in visual acuity equals what
Poorer the vision
Measurement other than 20/20 indicates what
Either refractive error or an optic disorder
If a patient is able to read some but not all the letters of the next smaller line indicate this by what
You adding number of letters read correctly on that line (20/25 +2) meaning thet can read all letters of 20/25 line and also 2 of the letters of the 20/20 line
What is used for young children 3-5 years old unable to read letters/use snellen chart
The tumbing e or HOTV
What does the LEA or LH symbols chart use
Four optotypes (circle square apple house)
What eye test consists of six pairs of cards with different accuities
The broken wheel test
What test is where the child identifies the card that has the broken wheels on a pictured car
Broken wheels card test
To assess for near vision what charts are used
Rosenbaum or Jaeger charge
A screening test for use with individuals at risk of macular degeneration is provided with the _____
Amsler grid
What monitors about 10 degrees of central vision and is used when retinal drusen bodies are seen during examination or when strong family history of macular degeneration
Amsler grid
What is a grid of straight lines that has a black dot that acts as fixation point
Amsler grid
What provides oils to the tear film in the eye
Meibomian glands
What distributes tears over the surface of the eye,limits amount of light entering, and protects from foreign bodies
The eyelid
What conjunctiva coats the inside and outside of the eyelids
Palpebral conjunctiva = inside, bulbar (ocular) conjuctiva = outer
What protects the anterior surface of the eye with the exception of the cornea and the surface of the eyelid contacting the glob
The bulbar conjunctiva
What is a biconvex transparent structure located immediately behind the iris
The lens
What changes the thickness of the lens permitting images of varied distances to be focused on the retina?
Thee ciliary body (contraction or relaxation)
When is accurate binocular vision acheived
When an image is fused on the retina by the cornea and the lens
Fibers located on the ______ decussate in the optic chiasm
Nasal retina
Accurate binocular vision requires the synchronous functioning of the what
Extra-ocular muscles
What is one of thee earliest visual responses of an infant
The mothers face
Lacrimal drainage is complete at when
At the time of term birth
By 3 to 4 months of age ____ vision development is complete
Binocular vision
When are the eyes developed enough to differentiate colors
By 6th months
Young children become less ____ with growth
Hyperopic
Adult visual acuity is achieved at about how old
4 years of age
What types of changes can eyes undergo in pregnant women
Hypersensitivity (change refractive power), tears increased lysozyme (greasy/blurred vision), mild corneal edema
Does intraocular fall or rise in pregnancy
Intraocular pressure falls notably during latter half of pregnancy
What is the major physiologic eye change that occurs with aging
Progressive weakening of accommodation (focusing power) = presbyopia
When does the lens become more rigid usually and the ciliary muscle becomes weaker
Age 45
Old fibers of the lens are compressed _____ forming denser ____ region that may cause what to happen
Centrally; central region; cause loss of clarity of the lens contributing to cataract formation
What cranial nerve is tested for small visual details and is essentially a measurement of central vision
CN 2
In the eye exam the smaller the fraction indicates what
The worse the vision
When do you perform a pinhole test
If visual acuity is recorded at a fraction less than 20/20
Expect improvement in visual acuity by at least one line on the chart if ______ is responsible for diminished acuity
Refractive power
Monocular diplopia is a ______ problem, binocular diplopia is an _____ problem
Optical; alignment
Measurement of near vision should also be tested in each eye separately with handheld card such as what
The rosenbaum pocket vision screener
What fields are you testing in peripheral field vision test
Nasal, temporal, superior, inferior fields
_____ most likely to produce confrontation abnormalities include stroke, retinal detachement, optic neuropathy, pituitary tumor compression at the optic chiasm, and central retinal vascular occlusion
Lesions
What is the order you carry out external exam of the eyes
Begin with appendages and move inward
If patients eyebrows are coarse or do not extend beyond temporal canthus, the patient may have what
Hypothyroidism
What is an elevated plaque of cholesterol deposited in macrophages most commonly in the nasal portion of the upper or lower lid
Xanthelasma
When examining a patient you have them lightly close their eyes and notice tremors what does this indicate
Hyperthyroidism
If one superior eyelid covers more of the iris than the other or extends over the pupil then ____ of that lid is present
Ptosis
Ptosis indicates a ____ or _____ weakness of the ____ muscle or a paresis of a branch of the ____ CN
Congenital or acquired; levator muscle; 3rd CN
When the lower lid is turned away from the eye it is called what
Ectropion
When the lid is turned inward toward the globe the condition is known as what
Entropion
In the case of entropion the lids eyelashes can cause what
Corneal/conjuctiva irritation, increasing secondary infection chances reports of foreign body sensation
An acuute suppurative inflammation of the follicle of an eyelas can cause an erythamatous or yellow lump called what
Hordeolum caused by staph
What usually causes blepharitis
Bacterial infection, seborrhea, psoriasis, roascease, allergic response
If closed eyelids do not completely cover the globe then it is a condition called what and results in what
Lagophthalmos cornea can become dried/infx
Pain on palpation of closed eye is consistent with what
Scleritis, orbital cellulitis, and cavernous sinus thrombosis
An eye that feels very firm and resists palption can indicate what
Severe glaucoma or retrobulbar tumor
An erythematous or cobblestone appearance especially on the ____ conjunctiva may indicate an _____
Tarsal conjunctiva; allergic/infectious conjunctivitis
Subconjunctival hemorrhages can occuur spontaneously during what
Labor/pregnancy
A pterygium is more common in people heavily exposed to what
UV light
Corneal sensitivity is controlled by CN ____ and is tested by touching whisp of cotton to the cornea
CN V
Decreased corneal sensation is often associated with what
Diabetes, herpes simplex and herpes zoster viral infx, after trigeminal neuralgia surgery
Blinking after corneal sensitivity test indicates what sensory CN are intact
CN 5 and motor fibers of CN 7
If arcus senilis is present before age 40 what can this indicate
Lipid disorder
What is a pupillary constriction to less than 2 mm
Miosis
The miotic pupil fails to do what
Dialate in the dark
What can cause miosis
Drugs like morphine or glaucoma meds
Pupillary dilation of more than 6mm an failure of pupils to constrict with light characterization of what
Mydriasis
Mydriasis is an accompaniement of a what
A coma or eye drops
What is an inequality of pupillary size and is common variation but can occur in other disease states
Aniscoria
If a pupil continues to dilate rather than constrict then what is present
Afferent pupillary defect or marcis gunn pupil
Bilateral, miotic, iregularly shaped pupils that fail to constrict with light but retain constriction with convergence are what
Argyll robertson pupil
A failure to respond to direct light but retaining constriction during accomodation is sometimes seen in patients with what
Diabetes/syphilis
What happens that causes sclera to become pigmented and appear either yellow or green
Liver or hemolytic disease
What appears as a dark slate gray pigment just anterior to the insertion of the medial recuts muscle
Senile hyaline plaque
What do you use to test the balance of the extraocular muscles
Corneal light reflex
What can cause no initial red reflex
Improper placement, cataract, hemorrhage into vitreous humor
If your patient is myopic you will use what lens
Minus (red) lens
If a patient is hyperopic or lacks a lens (aphakic) you will use what ophthalmascope lens
You will need a plus lense
Characteristics during a ophthalmologic exam inclduing narrowing of vessels, increased vascular toruosity, copper wiring, arteriovenous nicking and retinal hemorrhage indicate what
HTN
Prominent epicanthal folds are expected in asian infants but can be suggestive of what
Down syndrome/ other congenital anomolies
Wide spacing of the eyes is known as what
Hypertelorism
What is the false appearance of strabismus
Pseudostrabismus
Brushfield spots strongly suggest what
Down syndrome
The anticipated visual acuity for children 3-5 is what
20/40
The anticipated visual acuity for children aged 6 and older is what
20/30 or better
What can help differentiate chronic htn and PIH in pregnant women
Retinal examinations
Vascular tortuosity, angiosclerosis, hemorrhage, and exudates may be seen in patients with what
Long standing history of HTN
Segmental arteriolar narrowing with wet, glistening appearance indicative of edem is in a patient with what
PIH
What is inflammation of the superficial layers of the sclera anterior to the insterion of the rectus muscles
Episcleritis
What is a deposition of calcium in the superficial cornea
Band keratopathy
What is a disruption of corneal epithelium and stroma
Corneal ulcer
What is it when both eyes do not focus on an object simultaneously but can focus with either eye
Strabismus e
What is it when there is interruption of sympathetic nerve innervation to the eye
Horner syndrome
What is it when there is dot hemorrhages or microaneurysms and the presence of hard/soft exudates
Non proliferative diabetic retinopathy
What is it with development of new vessels as result of anoxic stimulaiton
Proliferative diabetic retinopathy
What is it when there is a creamy white appearance of retinal vessels that occurs with excessively high serum triglyceride levels
Lipemia retinalis
What is an autosomal recessive disorder in which genetic defects cause cell death predominantly in the rod photoreceptors
Retinitis pigmentosa
What is a disease of the optic nerve where the nerve cells die usually due to high intraocular pressure
Glaucoma
What is an inflammatory process involving both choroid and the retina
Chorioretintitis
What is disruption of normal progression of retinal vascular development in preterm infant
Retinopathy of prematurity
What is it when part of the retina degenerates
Macular degeneration
