Eye

Front 1

What cranial nerves innervate the eye?

Back 1

The four rectus and two oblique muscles attached to the eye are innervated by cranial nerves III (oculomotor), IV (trochlear), and VI (abducens)
The eye itself is a direct embryologic extension of the brain and is connected to the brain by cranial nerve II, the optic nerve

Front 2

What is the external eye is composed of?

Back 2

eyelid, conjunctiva, lacrimal gland, eye muscles, and the bony skull orbit

Front 3

What does the orbit contain?

Back 3

The orbit also contains fat, blood vessels, nerves, and connective tissue that support the eye

Front 4

What is the eyelid composed of?
What is the function of the eyelid?

Back 4

skin, striated muscle, the tarsal plate, and conjunctiva
The eyelid distributes tears over the surface of the eye, limits the amount of light entering it, and protects the eye from foreign bodies

Front 5

What is the conjuntiva?

Back 5

The conjunctiva is a thin mucous membrane covering and protecting the anterior surface of the eye with the exception of the cornea and the surface of the eyelid in contact with the globe.

Front 6

Were is the lacrimal gland?
Where do tears flow over and into?

Back 6

temporal region of the superior eyelid
Tears flow over the cornea and drain via the canaliculi to the lacrimal sac and duct and then into the nasal meatus

Front 7

What are the six muscles of the eye?

Back 7

the superior, inferior, medial, and lateral rectus muscles and the superior and inferior oblique muscles

Front 8

What are the three separate coats of the internal eye?
What does the middle layer contain?
What does the inner layer contain?

Back 8

The outer wall of the eye is composed of the sclera posteriorly and the cornea anteriorly.
The middle layer or uvea consists of the choroid posteriorly and the ciliary body and iris anteriorly.
The inner layer of nerve fibers is the retina.

Front 9

What is the Sclera?
What does it do?

Back 9

The sclera is the dense, avascular structure that appears anteriorly as the white of the eye.
It physically supports the internal structure of the eye.

Front 10

What does the Cornea constitute?
What kind of innervation?
Blood supply?
What function does it have a part in?

Back 10

The cornea constitutes the anterior sixth of the globe and is continuous with the sclera.
It is optically clear, has rich sensory innervation, and is avascular.
It is a major part of the refractive power of the eye.

Front 11

What makes the uveal tract?

Back 11

The iris, ciliary body, and choroids comprise the uveal tract

Front 12

What is the Iris?
What does it do to light?

Back 12

The iris is a circular, contractile muscular disk containing pigment cells that produce the color of the eye.
The central aperture of the iris is the pupil, through which light travels to the retina
By dilating and contracting, the iris controls the amount of light reaching the retina.

Front 13

What does the ciliary body produce and what does it control?

Back 13

The ciliary body produces the aqueous humor and contains the muscles controlling accommodation

Front 14

What is the choroid ?

Back 14

The choroid is a pigmented, richly vascular layer that supplies oxygen to the outer layer of the retina.

Front 15

Where is the lens?
How does it affect images?

Back 15

the lens is a biconvex, transparent structure located immediately behind the iris. It is supported circumferentially by fibers arising from the ciliary body. The lens is highly elastic, and contraction or relaxation of the ciliary body changes its thickness, thereby permitting images from varied distances to be focused on the retina.

Front 16

What is the retina?
How does it transform light to information?

Back 16

The retina is the sensory network of the eye.
It transforms light impulses into electrical impulses, which are transmitted through the optic nerve, optic tract, and optic radiation to the visual cortex and then to consciousness in the cerebral cortex

Front 17

What is the macula the site of?
What originates at the optic disc?

Back 17

The macula, or fovea, is the site of central vision
optic disc, from which the optic nerve originates

Front 18

When does the eye start to form in fetuses?
At birth, what is the term used to describe the eye and why?
What is fully develop at birth? What needs time to mature?
When do the lacrimal gland produce full tears?
When binocular vision complete? Color?

Back 18

first 8 weeks of gestation
hyperopic, with a visual acuity of less than 20/400
peripheral vision is fully developed at birth, central vision matures later
2-3 weeks
3-4 months , 6 months

Front 19

When is adult visual acuity normally fully developed?

Back 19

4 years of age

Front 20

What changes does the eye go through during pregnancy?

Back 20

physiologic and hormonal adaptations
Refractory power
Tears increase lysozmes (blur vision for contacts)
No new lens till after pregnancy
Diabetic retinopathy may worsen significantly. Mild corneal edema and thickening associated with blurred vision occur, especially in the third trimester

Front 21

What major physiologic changes do ALL older adults have with the eye?

Back 21

progressive weakening of accommodation (focusing power) known as presbyopia
45 years of age, the lens becomes more rigid and the ciliary muscle becomes weaker
lens also continues to form fibers
Old fibers are compressed centrally, forming a denser central region that may cause loss of clarity of the lens and contribute to cataract formation.

Front 22

What causes blurry vision as compared to what causes double vision?

Back 22

Blurred vision represents a problem with visual acuity and there are many causes.
Diplopia is the perception of two images and may be monocular or binocular. Monocular diplopia is an optical problem; binocular diplopia is an alignment problem.

Front 23

What are Risk Factors for Cataract Formation?

Back 23

Steroid medication use
Exposure to ultraviolet light
Cigarette smoking
Diabetes mellitus
Aging

Front 24

What is visual acuity?
What cranial nerve is testing visual acuity for?
Which chart do you use for distance vision?
Which chart for near vision

Back 24

the discrimination of small details
tests cranial nerve II (optic nerve) and is essentially a measurement of central vision
Snellen Chart
Rosenbaum Pocket Vision Screener (14inch 35cm)

Front 25

What Factors can Affect Visual Acuity Testing?

Back 25

Testing of visual acuity involves many complex factors not necessarily related to the ability to see the test object. Motivation and interest (including malingering or hysteria) as well as intelligence and attention span can modify the results of all sensory testing.

Front 26

In reading a visual acuity measurement, what is the numerator and what is the denominator?
What is considered legally blind?

Back 26

numerator indicates the distance of the patient from the chart (e.g., 20 feet or 6 m), and the denominator indicates the distance at which the average eye can read the line.
Thus 20/200 (6/60) means that the patient can read at 20 feet (6 m) what the average person can read at 200 feet (6 m). The smaller the fraction, the worse the vision.
Vision not correctable to better than 20/200 is considered legal blindness

Front 27

What is the point of the pinhole test?

Back 27

If the visual acuity is recorded at a fraction less than 20/20 (or 6/6), you can perform a pinhole test to see if the observed decrease in acuity was caused by a refractive error.
This maneuver permits light to enter only the central portion of the lens. It 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

Front 28

How do you test Peripheral vision?
Describe the angles

Back 28

Fingers coming from all sides with one eye both patient and doctor covered
fields describe an angle of 60 degrees nasally, 90 degrees temporally, 50 degrees superiorly, and 70 degrees inferiorly.

Front 29

What does a positive Confrontation Test suggest?

Back 29

The confrontation test is imprecise and can be considered significant only when it is abnormal. Lesions most likely to produce confrontation abnormalities include stroke, retinal detachment, optic neuropathy, pituitary tumor compression at the optic chiasm, and central retinal vascular occlusion.

Front 30

What color testing is important to test for? Why?

Back 30

Red testing may be particularly helpful in determining subtle optic nerve disease, even when visual acuity remains nearly normal. An afferent pupillary defect often coexists with a red defect

Front 31

What eyebrow features can show hypothyroidism?

Back 31

If the patient's eyebrows are coarse or do not extend beyond the temporal canthus, the patient may have hypothyroidism

Front 32

periorbital edema is always abnormal; the significance varies directly with the amount. It may represent….

Back 32

presence of thyroid eye disease, allergies, or (especially in youth) the presence of renal disease

Front 33

What is xanthelasma?

Back 33

elevated plaque of cholesterol deposited in macrophages most commonly in the nasal portion of the upper or lower lid
slightly raised, oval irregularly shaped, yellow-tinted lesions on the periorbital tissues that represent depositions of lipids and may suggest that the patient has an abnormality of lipid metabolism

Front 34

What does Ptosis of the eyelid indicate?

Back 34

Ptosis indicates a congenital or acquired weakness of the levator muscle or a paresis of a branch of the third cranial nerve

Front 35

What is ectropion?

Back 35

When the lower lid is turned away from the eye, ectropion is present and may result in excessive tearing

Front 36

What is the inferior punctum?

Back 36

The inferior punctum, which serves as the tearcollecting system, is pulled outward and cannot collect the secretions of the lacrimal gland.

Front 37

What is Entropion?
What do patients complain about?

Back 37

When the lid is turned inward toward the globe, a condition known as entropion the lid's eyelashes may cause corneal and conjunctival irritation, increasing the risk of a secondary infection. The patient often complains of a foreign body sensation.

Front 38

What causes Crusting along the eyelashes?

Back 38

Crusting along the eyelashes may represent blepharitis caused by bacterial infection, seborrhea, psoriasis, a manifestation of rosacea, or an allergic response

Front 39

What can acute suppurative inflammation of the follicle of an eyelash can cause?
From what?

Back 39

An acute suppurative inflammation of the follicle of an eyelash can cause an erythematous or yellow lump. This hordeolum or sty is generally caused by staphylococcal organisms

Front 40

What is it called when a patient cannot completely close their eyelids and cover the globe?
What can cause this?

Back 40

Lagophthalmos
cornea may become dried and be at increased risk of infection. Thyroid eye disease, seventh nerve palsy (Bells or other causes), and overaggressive ptosis or blepharoplasty surgery are common causes.

Front 41

What does an eye that feels very firm and resists palpation may indicate?

Back 41

glaucoma, hyperthyroidism, or the presence of a retrobulbar tumor.

Front 42

What does an erythematous or cobblestone appearance, especially on the tarsal conjunctiva, indicate?

Back 42

allergic or infectious conjunctivitis

Front 43

Bright red blood in a sharply defined area surrounded by healthy-appearing conjunctiva indicates ?

Back 43

subconjunctival hemorrhage
The blood stays red because of direct diffusion of oxygen through the conjunctiva.

Front 44

What is pterygium?
Where is the common site?
Who is it more common in?

Back 44

abnormal growth of conjunctiva that extends over the cornea from the limbus. It can interfere with vision if it advances over the pupil.
commonly on the nasal side but may arise temporally as well
more common in people heavily exposed to ultraviolet light.

Front 45

What controls Corneal sensitivity?
How do you test it?
What is Decreased corneal sensation often associated with?

Back 45

cranial nerve V (trigeminal nerve), is tested by touching a wisp of cotton to the cornea
expected response is a blink, which requires intact sensory fibers of cranial nerve V and motor fibers of cranial nerve VII (facial nerve).
Decreased corneal sensation is often associated with herpes simplex infection.

Front 46

What is corneal arcus (arcus senilis)?
What does this suggest if the patient is under 40?
What is a complete circle?

Back 46

lipids deposited in the periphery of the cornea
complete circle (circus senilis)
If present before 40 years of age, arcus senilis may indicate a lipid disorder, most commonly type II hyperlipidemia.

Front 47

Acquired heterochromia may be associated with what conditions?

Back 47

tumors, trauma, and recently with several glaucoma medications

Front 48

When evaluating the optic nerve, what reaction are you looking for and what is the test called?

Back 48

Look for an afferent pupillary defect by performing the swinging flashlight test
Shine the light in one eye and then rapidly swing to the other. There should be a slight dilation in the second eye while the light is crossing the bridge of the nose but it should constrict equally to the first eye as the light enters the pupil. Repeat going in the other direction. The motion of the pupil in the second to be illuminated eye should be down. If it continues to dilate rather than constrict, an afferent pupillary defect is present

Front 49

When do you test for pupillary response to accommodation ?
A failure to respond to direct light but retaining constriction during accommodation is sometimes seen in what two conditions?

Back 49

Testing for pupillary response to accommodation is of diagnostic importance only if there is a defect in the pupillary response to light.
A failure to respond to direct light but retaining constriction during accommodation is sometimes seen in patients with diabetes or syphilis

Front 50

What is Miosis?
What can commonly cause this?

Back 50

Miosis is pupillary constriction to less than 2 mm.
The miotic pupil fails to dilate in the dark. It is commonly caused by ingestion of drugs such as morphine, but drugs that control glaucoma may cause miosis as well.

Front 51

What is mydriasis?
What does this accompaniment?

Back 51

Pupillary dilation of more than 6 mm and failure of the pupils to constrict with light characterize mydriasis.
Mydriasis is an accompaniment of coma, whether caused by diabetes, alcohol, uremia, epilepsy, or brain trauma, or may be caused by the use of some eyedrops including some glaucoma medications and atropine or similar medications used in management of amblyopia in children

Front 52

What is Anisocoria?

Back 52

Anisocoria, the inequality of pupillary size, is a common variation but may also occur in a large range of disease states.

Front 53

What happens to the sclera in liver disease?

Back 53

If liver disease is present, the sclerae may become pigmented and appear either yellow or green.

Front 54

Is a Senile Hyaline plaque a clinical problem in the sclera?

Back 54

Senile hyaline plaque appears as a dark, slate gray pigment just anterior to the insertion of the medial rectus muscle .Its presence does not imply disease but should be noted.

Front 55

What conditions does an enlarged lacrimal glands suggest?
What do patients complain about?

Back 55

The lacrimal glands are rarely enlarged but may become so in some conditions such as tumors, lymphoid infiltration, sarcoid disease, and Sjögren syndrome.
Despite the enlargement, the patient may complain of dry eyes because the glands produce inadequate tears

Front 56

What is nystagmus?
What is jerking nystagmus?

Back 56

the involuntary rhythmic movements of the eyes that can occur in a horizontal, vertical, rotary, or mixed pattern
Jerking nystagmus, characterized by faster movements in one direction, is defined by its rapid movement phase. For example, if the eye moves rapidly to the right and then slowly drifts leftward, the patient is said to have nystagmus to the right.

Front 57

What is Lid lag and what condition does it suggest?

Back 57

Lid lag, the exposure of the sclera above the iris when the patient is asked to follow your finger as you direct the eye in a smooth movement from ceiling to floor, may indicate thyroid eye disease

Front 58

When do you perform the cover uncover test?

Back 58

When there is an imbalance found with the corneal light reflex test, perform the cover-uncover test

Front 59

What is the cover-uncover test? How do you perform it?
What conditions can a positive result indicate?

Back 59

To perform the cover-uncover test, ask the patient to stare straight ahead at a near fixed point. Cover one eye and observe the uncovered eye for movement as it focuses on the designated point. Remove the cover and watch for movement of the newly uncovered eye as it fixes on the object. Repeat the process, covering the other eye. Movement of the covered or uncovered eye may indicate either esotropia or exotropia. Such a finding mandates referral to an ophthalmologist

Front 60

What does a Absence of the red reflex mean?

Back 60

Absence of the red reflex is often the result of an improperly positioned ophthalmoscope, but it may also indicate total opacity of the pupil by a cataract or by hemorrhage into the vitreous humor.

Front 61

When you illuminate the iris nasally, what does this portion not being lighted up suggest?

Back 61

This portion of the iris is not lighted when the patient has a shallow anterior chamber, indicating a risk of acuteangle glaucoma. Mydriatics should be avoided in these patients.

Front 62

What are two other names for he macula?
What is this a site of?
Where is it located?

Back 62

also called the fovea centralis or macula lutea.
The site of central vision,
it is located approximately 2 disc diameters temporal to the optic disc

Front 63

What does Myelinated nerve fibers look like?
What condition does this suggest?

Back 63

appear as a white area with soft, ill-defined peripheral margins. The area is usually continuous with the optic disc. The nerve fiber layer is on the innermost surface of the retina. Note how the myelinated nerve fibers obscure areas of the retinal blood vessels, particularly inferiorly. This finding is due to the fact that the vessels lie deeper in the retina.
No physiologic significance.

Front 64

How is Papilledema characterized?
What causes it?

Back 64

loss of definition of the optic disc margin that initially occurs superiorly and inferiorly and then nasally and temporally.
It is caused by increased intracranial pressure transmitted along the optic nerve. The central vessels are pushed forward, and the veins are markedly dilated. Venous pulsations are not visible and cannot be induced by pressure applied to the globe. Venous hemorrhages may occur. Initially vision is not altered

Front 65

What is Glaucomatous optic nerve head cupping ?
What causes it
How does it look

Back 65

result of increased intraocular pressure with loss of nerve fibers and the death of ganglion cells. Occasionally atrophy occurs unilaterally; so you should always compare the cupping on the two retinae. Blood vessels may disappear over the edge of the physiologic disc and be seen again deep within the disc. Blood vessels may also be displaced nasally. Impairment of the blood supply may lead to optic atrophy, causing the disc to appear much whiter than usual. The cup is usually not particularly enlarged in contrast to glaucomatous atrophy. Peripheral visual fields are constricted

Front 66

How does a drusen body look?
What causes it?
What is it a precursor to?

Back 66

Drusen bodies can appear as small, discrete spots that are slightly more yellow than the retina. With time the spots enlarge. Similar appearing lesions may occur in many conditions that affect the pigment layers of the retina, but most commonly they are a consequence of the aging process and depending on size and number, are a precursor of senile macular degeneration

Front 67

What test do you do when drusen bodies are noted?
What does this test for?

Back 67

When drusen bodies are noted to be increasing in number or in intensity of color, the individual should be given an Amsler grid
The grid is used to evaluate central vision

Front 68

What does a hemorrhage at the disc margin often indicate?

Back 68

A hemorrhage at the disc margin often indicates poorly controlled glaucoma or undiagnosed glaucoma

Front 69

What vitamins has been demonstrated in preservation of vision with the reduction of age-related macular degeneration in individuals?

Back 69

taking high-dose antioxidants plus zinc.
Those treated with antioxidants (vitamin C, 100 mg; vitamin E, 400 International units; beta carotene, 15 mg; zinc, 80 mg, as zinc oxide; and copper, 2 mg, as cupric oxide) had a significantly better preservation of vision when compared with those treated with antioxidants, zinc and copper alone, or placebo

Front 70

What is Group I of the KWB classification?
Group II?

Back 70

Group I of the KWB classification is characterized by increased light reflex from the arterioles. There is moderate arteriolar attenuation and focal constriction. No arterialvenous changes at crossing are noted.
Group II is marked by the appearance of arterialvenous crossing changes. Arterioles are reduced to about one half of the usual size, and areas of localized constriction may be observed.

Front 71

What is Group III of the KWB classification?
Group IV?

Back 71

Group III is characterized by a shiny retina and by the appearance of cotton wool spots, which represent ischemic infarcts of the retina. These are gray areas with poorly defined margins. Hemorrhages may also be present.
Group IV is characterized by the appearance of papilledema.

Front 72

What is the Keith-Wagner-Barker (KWB) system (Keith, Wagner, Barker, 1939)?
What does it evaluate?

Back 72

Retinal changes associated with hypertension which evaluates changes in the vascular supply, the retina itself, and the optic disc. For accurate rating, the changes should be present bilaterally.
The arterial-venous size ratio is usually 3:5. That ratio decreases as arterioles become smaller because of smooth muscle contraction, hyperplasia, or fibrosis.

Front 73

How do you get an infant to open their eyes?

Back 73

Examining the newborn's eyes in a dimly lit room often encourages the baby to open the eyes. Holding the infant upright, suspended under its arms, or holding the baby at one's shoulder, the infant then looking behind the holder, also prompts the eyes to open

Front 74

What conditions does Prominent epicanthal folds suggest?

Back 74

Prominent epicanthal folds are an expected variant in Asian infants, but they may be suggestive of Down syndrome or other genetic anomalies in children of other ethnic groups

Front 75

How do you detect the sunsetting sign?
What does a positive result suggest?

Back 75

To detect the sunsetting sign, rapidly lower the infant from upright to supine position. Look for sclera above the iris.
This sign may be an expected variant in newborns; however, it also may be observed in infants with hydrocephalus and brainstem lesions

Front 76

What is hypertelorism? And what is it associated with?

Back 76

Observe the distance between the eyes, looking for a wide spacing, or hypertelorism, which may be associated with craniofacial defects including some with mental retardation.

Front 77

What is Pseudostrabismus?
What can cause this?
When does it go away?

Back 77

Pseudostrabismus, the false appearance of strabismus
caused by a flattened nasal bridge or epicanthal fold, is an expected variant in Asian and Native American/American Indian infants, as well as in some whites.
Pseudostrabismus generally disappears by about 1 year of age. Use the corneal light reflex to distinguish pseudostrabismus from strabismus. An asymmetric light reflex may indicate a real strabismus or hypertelorism

Front 78

Enlarged corneas in an infant may be a sign of __?__

Back 78

congenital glaucoma

Front 79

What does a swollen or edematous newborn's eyelids accompanied by conjunctival inflammation and drainage may represent?

Back 79

The newborn's eyelids may be swollen or edematous from birth trauma , but if accompanied by conjunctival inflammation and drainage, may represent ophthalmia neonatorum.

Front 80

What is coloboma?
What does it suggest in an infant?

Back 80

A coloboma, or keyhole pupil, is often associated with other congenital anomalies

Front 81

What are Brushfield spots?
What do they strongly suggest?

Back 81

White specks scattered in a linear pattern around the entire circumference of the iris, called Brushfield spots, strongly suggest Down syndrome or mental retardation.

Front 82

Opacities or interruption of the red reflex in and infant may indicate what conditions?

Back 82

Opacities or interruption of the red reflex may indicate congenital cataracts or retinoblastoma or other serious intraocular pathology

Front 83

What is the Visual Acuity at the following ages?
3 years
4 years
5 years
6 years

Back 83

3 years 20/50 or better
4 years 20/40 or better
5 years 20/30 or better
6 years 20/20

Front 84

When you are testing visual acuity in the child, any difference in the scores between the eyes should be noted. A two-line difference (e.g., 20/50 and 20/30) suggests what condition?

Back 84

amblyopia

Front 85

What does Retinal examination in the pregnant woman can help differentiate between?

Back 85

chronic hypertension and PIH

Front 86

Vascular tortuosity, angiosclerosis, hemorrhage, and exudates may be seen in pregnant patients with

Back 86

long-standing history of hypertension

Front 87

What symptoms do PIH patients show?

Back 87

In the patient with PIH, however, there is segmental arteriolar narrowing with a wet, glistening appearance indicative of edema. This finding is not exclusive to pregnant women. Hemorrhages and exudates are rare. Detachment of the retina may occur with spontaneous reattachment after hypertension is successfully controlled

Front 88

What is Exophthalmos?
What is the most common cause?
What about unilateral?

Back 88

increase in the volume of the orbital content, causing a protrusion of the globes forward
It may be bilateral or unilateral. The most common cause is Graves' disease, but when the exophthalmos is unilateral, a retro-orbital tumor must be considered, even though thyroid eye disease is the most common cause of unilateral proptosis as well.
Retraction of the upper lid and exposure of the sclera above the iris may exaggerate the appearance of exophthalmos.

Front 89

What is considered Eye Protrusion?
What factors produce this?

Back 89

The mean protrusion of the eye for black males exceeds that of white males by 2 mm. The same measurement in black females exceeds that of white females by 2.4 mm.
This is due to the more shallow orbits of blacks and to other craniofacial variations between blacks and whites.

Front 90

What is Episcleritis?
What conditions cause this?

Back 90

inflammation of the superficial layers of the sclera anterior to the insertion of the rectus muscles . It is generally localized, with a purplish elevation of a few millimeters.
Often the cause of the inflammation is unknown, but it is a common manifestation of Crohn's disease, rheumatoid arthritis, and other autoimmune disorders

Front 91

How is “Band keratopathy” produced?
Describe it
Where is this finding most commonly seen?

Back 91

produced by the deposition of calcium in the superficial cornea.
It appears as horizontal grayish bands interspersed with dark areas that look like holes. Band keratopathy appears as a line where the eyelids close just below the pupil; it passes over the cornea rather than around the iris as arcus senilis does.
This finding is most commonly seen in patients with chronic corneal disease but may occur in patients with hyperparathyroidism and occasionally in individuals with renal failure or syphilis.

Front 92

What are Corneal ulcers?
Caused by?
What increases the risk of this condition?

Back 92

disruption of the corneal epithelium and stroma
caused by viral or bacterial infection, or by desiccation because of incomplete lid closure or poor lacrimal gland function.
Wearing contact lenses increases the risk of developing bacterial ulceration in the otherwise healthy eye. Fig. 11-37 shows an ulcer in the lower temporal quadrant of the left cornea stained with rose Bengal

Front 93

What is Strabismus?

Back 93

Strabismus is a condition in which both eyes do not focus on an object simultaneously.
The condition may be paralytic, caused by impairment of one or more extraocular muscles or their nerve supply

Front 94

What is Nonparalytic strabismus?
How do you detect it?
This can be a sign of what condition?

Back 94

Nonparalytic strabismus has no primary muscle weakness. The patient can focus with either eye but not with both simultaneously .
It is detected by having the patient observe a near object. When one eye is covered, the other one will move to focus on the object if the covered eye was the dominant one .
Nonparalytic strabismus can be the presenting sign of intraocular pathology producing poor vision such as an infantile cataract or a retinoblastoma.

Front 95

What are Contributing Factors to Miosis?

Back 95

Iridocyclitis; miotic eye drops (e.g., pilocarpine given for glaucoma); drug abuse

Front 96

What are Contributing Factors to Mydriasis (pupillary dilation; usually more than 6 mm in diameter)?

Back 96

Iridocyclitis;
mydriatic or cycloplegic drops (e.g., atropine);
midbrain (reflex arc) lesions or hypoxia;
oculomotor (CN III) damage;
acute angle glaucoma (slight dilation);
drug abuse

Front 97

What are Contributing Factors to Failure to respond (constrict) with increased light stimulus?

Back 97

Iridocyclitis; retinal degeneration; optic nerve (CN II) destruction; midbrain synapses involving afferent pupillary fibers or oculomotor nerve (CN III) (consensual response is also lost); impairment of efferent fibers (parasympathetic) that innervate sphincter pupillae muscle, mydriatics

Front 98

What are Contributing Factors to Argyll Robertson pupil?

Back 98

Bilateral, miotic, irregularly shaped pupils that fail to constrict with light but retain constriction with convergence;
pupils may or may not be equal in size;
commonly caused by neurosyphilis or lesions in midbrain where afferent pupillary fibers synapse

Front 99

What are Contributing Factors to Anisocoria (unequal size of pupils)?

Back 99

Congenital (approximately 20% of healthy people have minor or noticeable differences in pupil size, but reflexes are normal) or caused by local eye medications (constrictors or dilators), or unilateral sympathetic or parasympathetic pupillary pathway destruction

Front 100

What are Contributing Factors to Iritis constrictive response?

Back 100

Acute uveitis is commonly unilateral; constriction of pupil accompanied by pain and circumcorneal flush (redness)

Front 101

What are Contributing Factors to Oculomotor nerve (CN III) damage?

Back 101

Pupil dilated and fixed;
eye deviated laterally and downward;
ptosis

Front 102

What are Contributing Factors to Adie pupil (tonic pupil)?

Back 102

Affected pupil dilated and reacts slowly or fails to react to light;
responds to convergence; caused by impairment of postganglionic parasympathetic innervation to sphincter pupillae muscle or ciliary malfunction;
often accompanied by diminished tendon reflexes (as with diabetic neuropathy or alcoholism)

Front 103

What causes Horner syndrome?
How do you detect it?

Back 103

Horner syndrome is caused by the interruption of the sympathetic nerve supply to the eye and results in ipsilateral miosis and mild ptosis.
Because the ptosis is subtle it may be best appreciated by noting that the amount of iris seen superiorly in the opposite eye is greater.
It is often caused by interruption of the cervical sympathetic trunk due to mediastinal tumors, bronchogenic carcinoma, metastatic tumors, or operative trauma

Front 104

What is the only common abnormality of the lens?
Other then age, what else can cause this condition?

Back 104

cataract formation
With aging, the lesion is generally central, but peripheral cataracts are common and may occur in conditions such as hypoparathyroidism. Chronic steroid use can cause significant visual disability from cataracts. Congenital cataracts can result from a number of genetic defects, maternal rubella, or other fetal insults during the first trimester of pregnancy

Front 105

Optic atrophy is the result what problem?
What is the primary symptom?
What procedure can make it appear like a patient has this problem but really doesn’t?

Back 105

Optic atrophy is the result of the death of nerve fibers and myelin sheaths.
The primary symptom of optic atrophy is loss of central or peripheral vision or both. The disc or a portion of it loses its yellowishpink hue and becomes stark white. It is often helpful to compare the disc color in each eye when assessing for optic atrophy .
Cataract surgery in one eye can make the disc look somewhat paler than the non-operated eye.

Front 106

What is DIABETIC RETINOPATHY (BACKGROUND) ?
Why is there soft or hard exudates?

Back 106

Background retinopathy is marked by dot hemorrhages or microaneurysms and the presence of hard and soft exudates.
Hard exudates are the result of lipid transudation through incompetent capillaries; these have sharply defined borders and tend to be bright yellow. They are generally superficial in the retina and are clustered around retinal vessels.
Soft exudates are caused by infarction of the nerve layer and appear as dull gray spots with poorly defined margins

Front 107

What is DIABETIC RETINOPATHY (PROLIFERATIVE)?
Where does it occur?
What can result is this condition gets worst?
What is the treatment for this?

Back 107

Proliferative retinopathy is the development of new vessels as the result of anoxic stimulation. The new vessels lack the supporting structure of healthy vessels and are likely to hemorrhage. These vessels grow out of the retina toward the vitreous humor, and visualization may require change in the lens setting of the ophthalmoscope.
It may occur in the peripheral retina or on the optic nerve itself.
Bleeding from these vessels is a major cause of blindness in patients with diabetes
Laser therapy

Front 108

What is LIPEMIA RETINALIS ?
What type of patients gets this condition?

Back 108

Lipemia retinalis is a dramatic condition that occurs when the serum triglyceride level exceeds 2000 mg/dL . The blood vessels become progressively pink and then white as the triglyceride level rises. This condition may be seen in diabetic ketoacidosis and in some of the hyperlipidemic states.

Front 109

What is RETINITIS PIGMENTOSA ?
What is the major problem with this condition?
What are the hallmarks of this disaease?

Back 109

Retinitis pigmentosa is an autosomal recessive condition characterized by the development of night blindness and loss of peripheral vision.
Optic atrophy "waxy pallor" narrowing of the arterioles, and peripheral "bone spicule" pigmentation are hallmarks of the disease

Front 110

What is CYTOMEGALOVIRUS INFECTION?
Who is it common in?
What is the nickname for this disease?

Back 110

Cytomegalovirus (CMV) infection is a common cause of blindness in immune compromised individuals such as those with HIV.
It is characterized by hemorrhage, exudates, and necrosis of the retina following the vascular pattern.
CMV infection is said to create a "pizza pie" appearance in the retina

Front 111

What is Glaucoma?
How might this occur?
What symptoms are in acute glaucoma?
What symptoms are in chronic glaucoma?

Back 111

Glaucoma is disease of the optic nerve wherein the nerve cells die, producing a characteristic appearance of the optic nerve (increased cupping).
It may occur acutely with dramatically elevated intraocular pressure if the iris blocks the exit of aqueous humor from the anterior chamber.
Acute glaucoma is accompanied by intense ocular pain, blurred vision, halos around lights, a red eye, and a dilated pupil. Occasionally patients complain of stomach pain, nausea, and vomiting.
In chronic glaucoma, which is more common, symptoms are absent except for gradual loss of peripheral vision over a period of years .

Front 112

What is Chorioretinal inflammation?
What is the most common cause?
What can change in the eye that affects the visual field?
What change in the eye happens but doesn’t affect the visual field

Back 112

inflammatory process that involves both the choroid and the retina. It results in a sharply defined lesion that is generally whitish yellow and becomes stippled with dark pigment in later stages ending with a chorioretinal scar.
laser therapy for diabetic retinopathy, but it may also be seen as a consequence of infectious agents such as histoplasmosis, cytomegalovirus or toxoplasmosis during fetal life.
A visual field defect can be detected in individuals with a large lesion. A chorioretinal scar appears similar to the whitish pigment seen when myelin sheath persists.
Myelin sheath persistence, however, causes no visual field defect

Front 113

What is a CHOROIDAL NEVUS ?
What do they suggest?

Back 113

Choroidal nevi are pigmented lesions of the choroid . They appear as darkened, well-defined areas of varying size beneath the retina.
They should be carefully observed to detect any enlargement or elevation that would suggest malignant change (e.g., melanoma).

Front 114

Defective vision or blindness in a single eye may be a consequence of what two problems?
What is the most common cause?

Back 114

degenerative changes within the eye itself (e.g., cataract) or it may stem from a lesion of the optic nerve anterior to its decussation.
The most common cause is interruption of the vascular supply to the optic nerve

Front 115

What causes a Bitemporal hemianopia?

Back 115

caused by a lesion-most commonly a pituitary tumor-interrupting the optic chiasm

Front 116

What causes a Homonymous hemianopia?

Back 116

Homonymous hemianopia can be caused by a lesion arising in the optic nerve radiation on either side of the brain.
These lesions occur after the optic chiasm and therefore involve nerve fibers arising from the same side of each eye and are caused by the interruption of the nerve fibers as they progress to the optic cortex

Front 117

What is RETINOBLASTOMA?
When does it arise? transmitted?
What is the initial sign?
What is seen on the Funduscopic examination?

Back 117

Retinoblastoma is an embryonal malignant tumor arising from the retina, often during the first 2 years of life.
The retinoblastoma may be transmitted either by an autosomal dominant trait or by a chromosomal mutation.
Initial signs are a white reflex (also called a cat's eye reflex) rather than the usual red reflex.
Funduscopic examination reveals an ill-defined mass arising from the retina. Often chalky-white areas of calcification can be seen

Front 118

What is the concern with RETINAL HEMORRHAGES IN INFANCY ?

Back 118

multiple hemorrhages in the optic fundus of an infant who was a victim of the shaken-baby syndrome.
Whenever retinal hemorrhages are seen, one must suspect infant abuse and investigate carefully.