Examination Of The Eye

Front 1

What is Exopthalmos (proptosis)?

Back 1

An abnormal protrusion of the eye from the Orbit.

Front 2

How can you determine whether a pt has proptosis (exophthalmos)?

Back 2

By placing a ruler at the edge of the lateral orbital angle and sighting from the side, the distance can be measured from the orbital angle to the anterior edge of the cornea.

If the distance exceeds 19mm for a white female, 21mm for a white male, 23mm for a black female or 24mm for a black male than the pt has exophthalmos.

Front 3

what is the most common cause of unilateral exophthalmos (proptosis) in children?

Back 3

bacterial orbital cellulits and retro-orbital tumors.

Front 4

what is the most common cause of bilateral exophthalmos (proptosis) in adults?

Back 4

Graves dz (which is an autoimmune disease that cause hyperthyroidism)

Front 5

Why is exophthalmos (proptosis) bad?

Back 5

B/c it causes corneal drying and limits the mobility of the globe.

Front 6

What is the tear coat?

Back 6

covers the anterior surface of the eye to prevent corneal drying, decrease friction b/e the eyelids and the cornea and is also anti-bacterial.

Front 7

What are Meibomian glands? What do they produce?

Back 7

A specialized sebaceous gland that produces the most superficial layer of the tear coat.

Front 8

What is the function of the most superficial layer of the tear coat?

Back 8

This layer is oily and functions to prevent evaporation of tears.

Front 9

What will happen to a pt who has a meibomian gland blockage, or anything that disrupts production of the superficial layer of the tear coat?

Back 9

Their tears will evaporate and cause dry eyes.

Front 10

What is the function of lacrimal glands?

Back 10

They produce the middle layer of the tear coat which is watery and composes the major component of tears.

Front 11

What is the function of eye goblet cells?

Back 11

Produce the inner layer of the tear coat, which is mucoid and helps disperse the water evenly across the anterior orbital surface.

Front 12

What is epiphora?

Back 12

Excessive tear production, which can be caused by eye irritation (inc. production of tears) or decreased tear drainage by punctal occlusion or nasolacrimal duct occlusion.

Front 13

What is the function of the nasolacrimal system?

Back 13

Drains the tears from the eye to the inferior meatus of the nose.

Front 14

What would happen if there was an occlusion in the nasolacrimal system?

Back 14

There would be epiphora or watery eyes.

Front 15

What is keratoconjunctivitis sicca?

Back 15

Decreased tear production that leads to dry eyes.

Front 16

What are the presenting symptoms of keratoconjunctivis sicca? what are the physical exam findinigs?

Back 16

Sys: A gritty sensation, burning and itching in one or both eyes.

PE: redness (conjunctival irritation) and corneal ulcers/scarring.

Front 17

What is the function of the Schirmer test? how is it performed?

Back 17

Evaluates tear production. Performed by applying a topical anesthetic, then placing a thin strip of filter paper in the inferior cul-de-sac. The pt closes their eye for 5 min. and the amount of wetness in the eye is measured.

If the amount of wetness is <5mm is abnormal, 5-10mm is iffy whether they have dry eyes or not.

Front 18

What is the function of the eyelids?

Back 18

Protect the cornea and anterior segment of the eye.

Front 19

What is the normal position of the eyelids?

Back 19

The upper eyelid normally lies b/e the corneoscleral junction (limbus) and the upper border of the pupil.

the lower lid margin lies along the lower corneoscleral junction.

Front 20

What is the palpebral fissure?

Back 20

The opening b/e the two eyelids.

Front 21

What is the action and innervation of the orbicularis ocuuli?

Back 21

Closes the upper eyelid during involuntary blinking and voluntary closure. It is innervated by CNVII

Front 22

What is Lagophthalmos? What pts typically develop Lagophthalmos? what does it cause?

Back 22

The inability to close the eyelids. It is typically present in comatose pts who have a decreased orbicularis tone and in pts who have CNVII palsy.

Lagophthalmos causes corneal drying and ulcerations.

Front 23

What is the action and innervation of the levator palpebrae superioris?

Back 23

It is innervated by CNIII and is responsible for raising the upper eyelid.

Front 24

what is the action and innervation of Muller's muscle?

Back 24

This muscle is innervated by postganglionic sympathetic fibers and aids the levator muscle in raising the upper eyelid.

Front 25

What presenting symptom in the eye is caused by sympathetic nerve palsy?

Back 25

causes the upper eyelid to droop 1-2mm.

Front 26

What presenting symptom in the eye is caused by 3rd cranial nerve palsy?

Back 26

Causes the upper eyelid to droop by >3mm.

Front 27

What is ptosis?

Back 27

Drooping of the upper eyelid.

Front 28

What is lid lag?

Back 28

A condition where the upper eyelid lags behind the globe when pts quickly change their direction of gaze from up to down.

Front 29

How can you detect lid lag?

Back 29

It is apparent when the sclera is visible b/e the upper eyelid and the corneoscleral junction during downward gaze.

Front 30

What causes lid lag?

Back 30

1. hyperthyroidism
2. hyperactivity of the sympathetic nervous system and Muller's muscle.

Front 31

What is a chalazion?

Back 31

A cystic nodule in the eyelid that develops from an obstruction in one of the ducts that drain a Meibomian gland.

Front 32

What are the presenting symptoms of a chalazion?

Back 32

A nodule on the inner surface of the eyelid that may be red and tender or painless. It will be red and tender if there is inflammation.

Front 33

What is a internal hordeolum? what causes it?

Back 33

A red, warm and tender nodule that occurs on the inner surface of the eyelid. It is caused by a bacterial infection of a meibomian gland.

Front 34

What is a external hordeolum (stye)? what causes it?

Back 34

A red, warm and tender nodule that occurs at the lid margin. It is caused by an acute bacterial infection of a sebaceous gland of Zeis at the base of a hair follicle.

Front 35

What are the presenting symptoms of internal and external hordeolums?

Back 35

Besides the nodule they cause a gritty sensation, itching, burning and pain in the affected eye.

Front 36

What are ectropion and entropion? what causes them? What do they cause?

Back 36

An outward or inward turning (respectively) of the eyelid margin. they are a result of aging and cause corneal irritation, excessive tearing or corneal drying.

Front 37

What is the conjunctiva?

Back 37

Except for the cornea, all parts of the anterior eye are covered by a thin, transparent, vascularized mucous membrane called the conjunctiva.

Front 38

What do glands in the conjunctiva produce?

Back 38

Mucoid secretions that contribute to the tear coat and also acts as a barrier against infection.

Front 39

What is the bulbar conjunctiva?

Back 39

It covers the surface of the sclera.

Front 40

What is the palpebral conjunctiva?

Back 40

Covers the inner surface of the eyelid.

Front 41

what is a pingueculum? what causes it? What are their effects?

Back 41

A yellow, fatty nodule of the bulbar conjunctiva on either side of the iris. Pingueculum develop w/ age, chronic sun exposure and from dry/windy conditions.

They are harmless and do not affect vision unless they become inflamed and interfere w/ wearing contact lenses.

Front 42

What are Pterygium? what causes it?

Back 42

A triangular fibrovascular thickening of the bulbar conjunctiva that grows slowly across the cornea (usually from the nasal side). It is usually caused by chronic UV exposure, though this is not certain.

Front 43

What are chemosis?

Back 43

Painless edema of the conjunctiva that develops as a consequence of several abnormalities.

Front 44

What abnormalities cause chemosis?

Back 44

1. Increased permeability of conjunctival capillaries due to allergic reactions or local ocular infections.
2. increased hydrostatic pressure in conjunctival capillaries due to SVC obstruction or right heart failure.
3. decreased oncotic pressure - in conjunctival capillaries due to increased albumin excretion (nephrotic syndrome) or decreased albumin synthesis (liver disease)
4. decreased lymphatic drainage - of the orbit due to local lymphatic obstruction (graves disease) or systemic lymphatic obstruction (heart failure)

Front 45

what are conjunctival hemorrhages?

Back 45

Occur in the palpebral conjunctiva or the bulbar conjunctiva when conjunctival blood vessels leak blood or rupture.

Front 46

What are tiny petechial conjunctival hemorrhages? what causes them?

Back 46

Occur in the palpebral conjunctiva as a result of small vessel vasculitis (inflammation) that may accompany autoimmune disease or infectious endocarditis.

Front 47

What are hyposphagma?

Back 47

large bulbar conjunctival hemorrhages that occur when conjunctival vessels rupture and bright red blood collects b/e the sclera and conjunctiva.

Front 48

What is bad about hyposphagma?

Back 48

They are painless but often very alarming. If they are recurrent they could indicate a coagulation defect.

Front 49

What is the cause of hyposphagma?

Back 49

They are most often caused by either a sudden increase in intravascular pressure which is caused by sneezing or coughing, or by local eye trauma such as occurs from rubbing the front of the eye.

Front 50

What is scleral icterus?

Back 50

"Jaundice"; is a yellow discoloration of the bulbar conjunctiva rather than the sclera. It is caused by hyperbilirubinemia (which is a [bilirubin] > 2.5-3.0).

An increased bilirubin results from hepatic dysfunction or biliary tract obstruction.

Front 51

What do blue sclera indicate?

Back 51

A classic finding of osteogenesis imperfecta. Decreased type I collagen in the sclera causes the sclera to become transparent and allow the darker (black) choroid to show through, giving the impression that the sclera is blue.

*Ehler's Danlos syndrome also causes blue sclera.

Front 52

When are blue sclera a normal finding?

Back 52

In newborns and infants.

Front 53

What is the cornea?

Back 53

A thin avascular tissue that is richly innervated w/ sensory nerve fibers from the ophthalmic branch of CNV.

Front 54

How does the cornea receive nutrients? how does it keep the cornea clear?

Back 54

It receives nutrients by extracting O2 from the air anteriorly and glucose from the aqueous humor posteriorly.

To maintain clarity the corneal endothelium pumps water from the corneal stroma to the aqueous humor.

Front 55

What is the limbus?

Back 55

A 1-2mm wide transitional zone located b/e the cornea and the sclera that identifies where the conjunctiva inserts.

Front 56

What provides the majority of the focusing power of the lens?

Back 56

The cornea and tear coat provide 70% of the focusing power of the eye while the lens provides 30% of the focusing power.

Front 57

What is "LASIK"?

Back 57

A surgical procedure that permanently changes the shape of the cornea. A microkeratome knife is used to cut a flap in the cornea leaving a hinge at one end. Then pulses from a computer-controlled laser vaporize a portion of the stroma and the flap is replaced.

Front 58

What is LASIK used to correct?

Back 58

Myopia (near-sightedness); hyperopia (far-sightedness); and astigmatism (corneal irregularities that cause blurred vision)