EPT6

Question 1

What mechanism explains the iris color change sometimes noted in pts on topical ophthalmic latanoprost?

Answer 1

Increased pigmentation associated with INC of melanin within iridial melanocytes

Question 2

Which is the MOST common cause of genetic visual impairment in infants and children?

Answer 2

Leber congenital amaurosis

Question 3

What is sorsby dystrophy?

Answer 3

Peripheral choroidal and outer retinal disease that typically manifests in adulthood

Question 4

When does choroideremia cause visual impairment?

Answer 4

Middle adulthood

Question 5

Which technique for measuring aniseikonia is considered to be the MOST accurate?

Answer 5

Space eikonometer

Rare to have, most clinicians just estimate aniseikonia with the rule that for every 1.00D of power difference, there will be ~1% induced aniseikonia

Question 6

If you add two soft CL’s how do you figure out the resultant power and axis?

Answer 6

1. Resultant cyl axis is between the cylinder lens axis
2. Resultant cyl axis is closer to the CL with more cyl power
3. Sum of spherical equivalents of the 2 cyl lenses will equal the spherical equivalent of the resultant cyl lens

Question 7

DEC synthesis of type 1 collagen is MOST likely result in which of the follow? Select 2

a. INC IOP
b. Corneal thinning
c. Blue sclera
d. Cataract formation
e. Vitreous syneresis

Answer 7

b. Corneal thinning
c. Blue sclera

NOTE: type 1 collagen is primarily located w/in the cornea and sclera. Thus, DEC synthesis of type 1 collagen is MOST likely to result in scleral thinning (noted as a blue sclera due to the visibility of the underlying uvea), as well as corneal thinning

Question 8

Type I collagen is found in which part of the cornea?

Answer 8

Stroma (450 um)

Question 9

Where is type IV collagen found in the cornea?

Answer 9

Basement membrane & Descemet’s Membrane

Question 10

Where is Type II collagen found in the cornea?

Answer 10

Bowman’s membrane

Question 11

What mucin types bind to goblet cells?

Answer 11

Mucin 1,4,6

Question 12

EBMD and Meesan affects what part of the cornea?

Answer 12

Basement Membrane

NOTE: thcikens w age, 8-10 weeks for regeneration

Question 13

Band Keratopathy, Pterygia, Reis-buckler dystrophy, and Keratoconus affects which part of the cornea?

Answer 13

Bowman’s Membrane

NOTE: strong barrier to injury, acellular, embryologically layed down (no regeneration)

Question 14

Macular dystrophy, granular dystrophy, and lattic dystrophy affects which part of the cornea?

Answer 14

Stroma

NOTE: hydrophilic, nerves enter here and move anteriorly

Question 15

What are the 2 effects of PTH?

Answer 15

1. Stimulation of osteoclast activity in bone

2. Stimulation of calcium reabsorption by the kidney

Question 16

The midbrain is involve in the control of which of the follow (select 3)?

a. Sensory innervation of the cornea
b. Innervation of the lateral rectus
c. Innervation of the Superior Oblique
d. Innervation of the levator palpebrae superioris
e. Motor activity to the muscles of facial expression
f. Pupillary constriction

Answer 16

c. Innervation of the Superior Oblique
d. Innervation of the levator palpebrae superioris
f. Pupillary constriction

NOTE: the midbrain contains nuclei for CN3/4, and the EW nucleus.

Question 17

Autoimmune damage to the salivary glands is MOST likely associated with which of the following clinical findings?

a. 11mm wetting after 5 min on Schirmer 1 testing
b. 6 sec TBUT
c. 4mm wetting after 5min on Schirmer 2 testing
d. 11mm wetting after 15 sec on phenol red thread test

Answer 17

c. 4mm wetting after 5min on Schirmer 2 testing

NOTE: autoimmune damage to the salivary glands (including the lac gland) causes Sjogren’s syndrome which is associated with ADDE. <5mm of wetting after 5min on Schirmer 2 testing is suggestive of ADDE

Question 18

What is the MOST common infectious cause of post-operative endophthalmitis?

Answer 18

Gram (+) bacteria

NOTE: our lids and lashes have gram (+)

Question 19

What is the MOST common clinical finding in toxic anterior segment syndrome following cataract extraction is?

Answer 19

Corneal edema

NOTE: marked diffuse corneal edema with little to no post seg inflammation Dx w/in first 12-48 hours following cat extraction. PS & suppurative conjunctivitis are LESS common but possible.

Question 20

Zeaxanthin and lutein are xanthophyll pigments that are PRIMARILY located where?

Answer 20

Inner segments of PR

Question 21

A posterior vitreous detachment is MOST commonly the result of:

a. INC type 2 collagen content of the vitreous
b. Formation of lacunae and inward collapse of the vitreal cortex
c. Loss of Weiger’s ligament in the anterior vitreous
d. Separation of the vitreous base from the retina

Answer 21

b. Formation of lacunae and inward collapse of the vitreal cortex

NOTE: result of INC vitreal liquefaction, which results in lacunae formation and inward collapse of the cortex.

Question 22

When does separation of the vitreous base from the retina most often occur?

Answer 22

Trauma and is NOT a cause of PVD

Question 23

What is the DIRECT role of RPE in the visual cycle?

Answer 23

Converting All-trans-Retinol to 11-cis retinol –> then oxidized to 11-cis retinal**

NOTE: RPE transports All-trans retinol into its cytoplasm via cellular retinol binding protein, where it is sequentially converted into 11-cis retinal. Many rod-cone dystrophies occur as a result of interruptions to this pathway

Question 24

Using a high powered add will have all of the following effects EXCEPT:

a. DEC WD
b. DEC FOV
c. DEC lateral magnification
d. INC relative distance magnification

Answer 24

c. DEC lateral magnification

Question 25

What is duane syndrome exactly?

Answer 25

A group of EOM disorders characterized by abduction and/or adduction deficits due to misrouting of CN6 & irregular innervation of a branch of CN3

Question 26

What is the index of refraction for an ideal thin film that minimizes reflections for an anterior chamber IOL (n=1.45) w/in the aqueous humor?

Answer 26

1.392 nf = (nL*nm)^0.5 nf=(1.45*1.336)^0.5=1.392 nf=index of film nL=index of IOL nm=index of aqueous

Question 27

For aquired and asymmetric color vision defects, which eye should you test monocularly first?

Answer 27

The POORER seeing eye!!!

Question 28

Which layers are absent at the foveola and why?

Answer 28

``` No bipolar cells No ganglion cells No INL No IPL No NFL ``` in order to minimize light scattering as light travels to the cone PR

Question 29

Which group of vessels exits the outer wall of schlemm's canal?

Answer 29

External collector channels (aka aqueous veins of Ascher) --> Episcleral plexus --> Anterior ciliary veins --> muscular veins --> S/I ophthalmic veins --> CS

Question 30

Which of the following is NOT an association of an acute, unilateral, non-granulomatous uveitis (SELECT 3): a. Juvenile rheumatoid arthritis b. Behcet's disease c. Fuchs' heterochromic iridocyclitis d. Ankylosing spondylitis e. Reactive arthritis f. Tuberculosis

Answer 30

a. Juvenile rheumatoid arthritis c. Fuchs' heterochromic iridocyclitis f. Tuberculosis (a) and (c) are both chronic non-granulomatous uveitis, most often uni in Fuch's and bilateral in JRA (f) is associated with chronic, bilateral, granulomatous uveitis that may be anterior, posterior, or panuveitis

Question 31

What is the MOA of Spironolactone?

Answer 31

It inhibits the actions of aldosterone in the late distal convoluted tubule (DCT) & the collecting duct of the nephron, leading to DEC absorption of NaCl & DEC excretion of K+

Question 32

Furosemide inhibits which cotransporter?

Answer 32

Na+/2Cl-/K+ cotransporter in the thick ascending loop of Henle

Question 33

If a bacterium were susceptible to both penicillin and erythromycin, then it would NOT be appropriate to Tx the pt w both antibiotics at the same time bc?

Answer 33

Penicillin is ONLY effective against growing cells Bc erythromycin inhibits cell growth, it will DEC the effectivity of penicillin if both medications are administered at the same time

Question 34

Which wavelengths are we most easily able to distinguish?

Answer 34

495nm and 590nm

Question 35

Which of the following CORRECTLY pairs the pt's age w the MOST appropriate VA test? a. 24 month old toddler who sits too close to the TV; broken wheel testing b. 11-month old infant w/o vision concerns; Allen symbols c. 9 month old infant w a suspected RET; ooptokinetic drum d. 30 month old toddler who squints; teller acuity cards

Answer 35

a. 24 month old toddler who sits too close to the TV; broken wheel testing Broken wheel testing is a forced choice test that is MOST appropriate for toddlers or children of pre-school age. Teller acuity cards, another forced choice method, are most appropriate for infants ages 6-18 months. Allen symbols are most appropriate for pre-school children (3 years of age or older) rather than an infant The OKN drum only assesses activity within the visual cortex & is not appropriate for determining the presence of strab or the risk of amblyopia

Question 36

Your pt w a Hx of RA presents w a complaint of redness OD w/o associated pain. You note focal blue-gray areas of the sclera w mild conjunctival injection and no associated keratitis. What is the MOST likely Dx?

Answer 36

Scleromalacia perforans NOTE: also known as necrotizing scleritis w/o inflammation. It is a common form of scleritis in pts with severe RA. Pts present w a bluish-gray hue of the sclera due to thinning that results from rearrangement of the scleral collagen fibers after resolution of the inflammation. Pts ofte have minimal hyperemia & pain. Nodula

Question 37

A 45 year old female complains of bilateral ocular burning, tearing, and a FB sensation that progressively worsens throughout the day. She also reports a Hx of chronic dry mouth. Which of the following is MOST appropriate to further evaluate this pt's symptoms?

Answer 37

Salivary gland biopsy R/O sjogren's

Question 38

What is the MOA of ophthalmic trifluridine?

Answer 38

It prevents viral DNA replication by inhibiting thymidine synthetase

Question 39

A pt who has experiences a TBI complains of difficulty finding the start of the next line when he finishes reading a line of text. Which of the following is MOST likely cause of his complaints? a. Bitemporal hemianopsia b. Left homonymous hemianopsia c. Right homonymous hemianopsia d. Binasal hemianopsia

Answer 39

b. Left homonymous hemianopsia

Question 40

A pt who smokes cigarettes notices a gradual onset of labored breathing and shortness of breath. He has a reduced FEV1/FVC ratio. Which of the following is the MOST likley Dx?

Answer 40

Pulmonary emphysema Enlarged air spaces & decreased elastic recoil - Dyspnea - Tachycardia - REDUCED FEV1/FVC ratio

Question 41

Which of the following wavelengths of light is MOST likely to damage the retina of a phakic elderly adult? a. 285 nm b. 370 nm c. 310 nm d. 210 nm

Answer 41

b. 370 nm Recall: UVA 400-315 UVB 315-280 UVC 280-100 UVC is absorbed by tears, cornea, and aq humor UVA and UVB will be transmitted by the lens to the retina in a young pt With age UVB is absorbed and almost all of UVA light

Question 42

What is Kearns-Sayre Syndrome? What are some ocular features?

Answer 42

Kearns-Sayre syndrome is considered a mitochondrial myopathy in which mitochondrial DNA deletions result in a clinical triad of signs. These signs include ocular features such as progressive external ophthalmoplegia (CPEO) and "salt and pepper" pigmented retinopathy (with predilection for the macula), as well as one or more systemic complications which can include heart block, cerebellar ataxia, or abnormally elevated cerebrospinal fluid protein.

Question 43

Which of these statements are FALSE about a sphero-cylindrical lens OR for a SCL? a. If the axis of the OR is the same as the axis of the spectacle Rx, INC cyl power in the soft toric CL b. If the axis of the OR is 090 degrees from the axis of the spectacle Rx, DEC the cyl power in the SCL c. For every 5 degrees of misalignment btwn the soft toric CL and the axis of the spectacle Rx, 1/4th of the original cyl power will manifest in the OR d. If the axis of the OR is oblique compared to the axis of the spectacle Rx, the soft toric CL has rotated

Answer 43

c. For every 5 degrees of misalignment btwn the soft toric CL and the axis of the spectacle Rx, 1/4th of the original cyl power will manifest in the OR NOTE: for every 5 degrees of misaligment btwn the soft toric CL position & the spectacle Rx, approx 1/6th of the original cyl power in the spectacle Rx will manifest in the sphero cylindrical OR. If the axis of the OR and spectacle lens Rx are the same, the soft toric CL is under-correcting the pt's astig; thus, the cyl power in the soft toric CL should be increased. If the axis of the OR is 090 away then subtract the OR from the pts astig If the axis of the OR and spec Rx are oblique, the axis of the soft toric CL is incorrect or the CL rotated on the eye

Question 44

All of the following may occur as a result of an aneurysm of the posterior communicating artery EXCEPT: a. impaired accommodation b. Limited abduction c. Limited supraduction d. Mydriasis e. Ptosis

Answer 44

b. Limited abduction A PCA aneurysm is the MOST common cause of a pupil-involved CN3 palsy. Impaired CN3 innervation results in Mydriasis (impaired iris sphincter), Ptosis (impaired levator), Poor accommodation (impaired ciliary muscle), & limited adduction, supraduction, and infraduction (poor innervation of the MR, SR, IO, and IR)

Question 45

Which of the following statements regarding visual development is INCORRECT? a. Accommodation & fusional vergence are present at birth b. Saccades are hypometric until ~6 years of age c. Stereopsis reaches adult levels at 6 months of age d. Near point of convergence is NOT detectable until 6 months of age

Answer 45

a. Accommodation & fusional vergence are present at birth NOTE: accommodation & fusional vergence do NOT develop ~1 month after birth

Question 46

A 53 year old female complains of spontaneous, intermittent, involuntary, bilateral, transient eyelid closure that most commonly occurs while reading or following exposure to bright lights. You detect adequate lid symmetry and good lid position, and all CNs are fully intact. The pt has no dysdiadochokinesia w rapid alternating movements & demonstrates a well-balanced & coordinated gait. What is the MOST likely Dx?

Answer 46

Benign essential blepharospasm NOTE: characterized by idiopathic bilateral lid closure causing transient blindness until the spasm resolves

Question 47

Which of the following ganglia provides parasympathetic innervation to the lacrimal gland to stimulate aqueous secretion?

Answer 47

Pterygopalatine! NOTE: parasympathetic innervation travels w the greater petrosal nerve of CN7 --> Postganglionic parasympathetic fibers join the zygomatic branch of V2 before joining the lacrimal nerve of V1 to innervate the lacrimal gland

Question 48

Which of the following is an example of an anastomosis btwn the internal and external carotid arteries that supply ocular structures? a. The infraorbital artery joins the facial artery to supply the lower eyelid and lacrimal sac b. The angular artery communicates with the dorsal nasal artery to supply the medial canthus c. the superficial temporal artery communicates w the facial artery to supply the superficial skin around the orbit d. the dorsal nasal artery communicates w the supratrochlear artery to supply the lacrimal sac

Answer 48

b. The angular artery communicates with the dorsal nasal artery to supply the medial canthus The angular artery (from the facial artery of the ECA) communicates w the dorsal nasal artery (from the OA of the ICA) and supplies blood to the medial canthus The infraorbital artery (from the maxillary artery of the ECA) joins w the dorsal nasal artery (from the OA of the ICA) to supply the lower eyelid and the lacrimal sac The superficial temporal artery from the ECA communicates w branches of the OA from the ICA The Supratrochlear artery does NOT communicate with branches of the ECA

Question 49

A choroidal melanoma is characterized by abnormal proliferation of melanocytes within which of the following layers?

Answer 49

Choroidal stroma RECALL: Choroidal melanomas are the MOST COMMON primary intraocular malignancies in adults.

Question 50

Light absorption by a PR results in what?

Answer 50

Closure of Na+ channels Hyperpolarization of the cell DEC glutamate release PR responds with graded potentials

Question 51

UV exposure to cells in the stratum basale of the eyelid is MOST likely associated w which of the following clinical findings?

Answer 51

Telangiectasia NOTE: damage to stratum basale of the eyelid results in the development of BCC. Recall that a key characteristic that DDx BCC from Squamous cell carcinomas (located w/in the stratum spinosum) is the presence of surface telangiectasia

Question 52

What is the physiological limit of VA in a theoretical human eye with perfect optics?

Answer 52

20/8 This is due to the cone diameter

Question 53

Your pt's palpebral fissure OD appears wider vertically compared to OS due to trauma. His right eye is non-seeing. The pt desires a spectacle lens OD that will cosmetically equalize (narrow) the appearance of his right eye in the vertical meridian only. What is the power of the right lens that would BEST address this pt's request? a. +1.00-1.00x180 b. +1.00-1.00x090 c. plano-2.00x180 d. plano-2.00x090

Answer 53

c. plano-2.00x180 Trying to minimize vertical meridian

Question 54

What are associated with idiopathic intracranial HTN?

Answer 54

Oral contraceptives, tetracyclines, Accutane, vitamin A, and Naladixic acid (a quinolone antibiotic)

Question 55

what test should be performed in order to determine the etiology of CME?

Answer 55

FA! Irvine Gass will leak

Question 56

A CR-39 spec lens has a back vertex power of +4.00D. If the lens has a center thickness of 3mm & is worn at a vertex distance of 10mm, the power mag produced by the lens is approx what?

Answer 56

1.05X 1/(1-h*Fv) h=10mm+3mm (distance from cornea to EP) 1.05X means 5% magnification due to the lens

Question 57

What is the greatest risk for developing a macular hole

Answer 57

Increasing age

Question 58

A pt with a Hx of an intracranial mass has an impaired optokinetic nystagmus response when the drum is rotated to the RIGHT. Where is the MOST likely location of the lesion?

Answer 58

Right Parietal Lobe Recall: Parietal lobe lesions can affect pursuits and therefore the OKN response. A parietal lobe lesion will inhibit pursuit movements on the same (ipsilateral) side of the lesion. When a OKN drum is spun to the right, the resultant eye movement in a normal pt will be tracking movement (smooth pursuit) to the right followed by a refixation (saccade) to the left. In this case, since the OKN response is impaired w the drum spinning ot the right, the right parietal lobe must be the area involved

Question 59

A pt presents w retinal hemorrhages and bilateral temporal optic nerve pallor on dilated fundus exam. Which of the following types of anemia is the MOST likely cause of these ocular findings?

Answer 59

Pernicious NOTE: pernicious anemia is caused by autoantibodies directed against parietal cells in the stomach, resulting in DEC production of intrinsic factor necessary for the absorption of vit B12. Inadequate intake of vit B12 is associated w retinal hemorrhages & temporal optic nerve pallor

Question 60

A 35 year old male presents w bilateral, yellow, elevated, plaque lesions within the upper medial portion of the eyelids. Which of the following tests is MOST appropriate?

Answer 60

Triglycerides, HDL, and LDL

Question 61

You devise a new test to determine whether pt has glaucoma. To determine the sensitivity and specificity of your test, you administer it to 100 pts who are known to have glaucoma and 100 pts who are healthy. Out of the 100 pts who have glaucoma, the test gives 96 positive results and 4 negative results. Out of the 100 pts who do not have glaucoma, the test gives 25 positive results and 75 negative results. What is the sensitivity and specificity of your new test?

Answer 61

96% sensitive 75% specific

Question 62

All of the following respiratory disease are characterized by a normal to elevated FEV1/FVC ratio EXCEPT: a. Toxoplasmosis b. Histoplasmosis c. Sarcoidosis d. Chronic bronchitis

Answer 62

d. Chronic bronchitis NOTE: the FEV1/FVC ratio measures how much air a pt can forcefully expire in one second vs total forced lung capacity. A normal to elevated FEV1/FVC ratio is characteristic of restrictive lung diseases (i.e. sarcoid, toxoplasmosis, and histoplasmosis). Chronic bronchitis is an obstructive lung disease that is characterized by a reduction in the FEV1/FVC ratio <80% ratio indicates obstructive lung disease

Question 63

If the trigeminothalamic pathway is severed at the level of the medulla, what would happen MOST likely? a. Proprioception b. Taste c. Light touch from contra side of face d. Pain from ipsi side of face

Answer 63

d. Pain from ipsi side of face NOTE: trigeminothalamic pathway carries pain and temperature info from face. Fibers enter brainstem at pons, descend to the spinal nucleus of CNV at the level of the medulla, and then decussate to ascend to the thalamus. Thus, a lesion at the medulla will result in loss of pain info on the ipsi side of the face

Question 64

Which of the following ocular striated muscles is the last to develop? a. Superior oblique b. Inferior rectus c. Superior rectus d. Levator palpebrae

Answer 64

d. Levator palpebrae The levator palpebrae is the last muscle to appear as it splits from the superior rectus during development. Recall that the orbital striated muscles are derived from mesodermal mesenchyme that differentiates into myoblasts

Question 65

How do interferons provide resistance against corneal epithelial dendritic keratitis?

Answer 65

They prevent the replication and production of new viruses within neighboring cells Recall that interferons are polypeptides produced by viral-infected cells that help to protect neighboring cells from viral infections. Although viruses can still penetrate neighboring cells, interferons prevent viral replication and the production of new virus particles

Question 66

A pt w a TBI to the LEFT FRONTAL LOBE will MOST likely show DEC function when making saccades in which direction?

Answer 66

To the Right Side NOTE: saccadic eye movements are generated by contralateral FEF (as well as the superior colliculus). Thus, damage to the left frontal lobe is MOST likely to affect saccades to the RIGHT side

Question 67

Topical ophthalmic PG analogs INC aqueous humor outflow through (SELECT 3): a. Vortex veins b. Anterior ciliary veins c. Aqueous veins of Ascher d. Schlemm's canal e. Ciliary Muscle fiber bundles

Answer 67

a. Vortex veins b. Anterior ciliary veins e. Ciliary Muscle fiber bundles Topical ophthalmic PG analogs INC aq humor outflow through the uveoscleral meshwork. Recall the aq humor that drains through the uveoscleral meshwork passes through ciliary muscle fiber bundles to the suprachoroidal space and sclera, or drains into the anterior ciliary veins or vortex veins. Aqueous humor drains through the corneoscleral meshwork through schlemm's canal. The aq veins of ascher (ext collector channels) then carry aq humor to the episcleral venous plexus NOTE: PG analogs also act on skin receptors activating phospholipase C to alter hair follicles

Question 68

Diabetic macular nonperfusion may result from loss of pericytes from which of the following? a. LPCA b. Haller's layer c. Sattler's layer d. Choriocapillaris

Answer 68

d. Choriocapillaris

Question 69

A pt presents w symptoms of amaurosis fugax and a Hollenhorst plaque OD. All of the following tests are indicated EXCEPT: a. CT scan b. Echocardiogram c. Carotid ultrasound d. FA

Answer 69

d. FA Pts w retinal embolia and/or amaurosis fugax are at a greater risk of development of TIAs and/or strokes. They should be referred immediately for a CT or MRI to determine whether a concomitant stroke is occuring. A carotid ultrasound and cardiac studies (i.e. EKG, echocardiogram) are also warranted to determine the source of the embolus.

Question 70

Which of the following definitions BEST describes radiant intensity? a. The amount of energy per second produced by a light source b. The amount of energy per second in a specific direction (or amount of space) produced by a light source c. The visual system's response to a given amount of energy per second produced by a light source d. The visual system's response to a given amount of energy per second in a specifc direction (or amount of space) produced by a light source

Answer 70

b. The amount of energy per second in a specific direction (or amount of space) produced by a light source a is radiant power c is luminance power d is luminance intensity

Question 71

Which of the following statements regarding visual development of the infant is FALSE? a. aprox half of the changes necessary for development of the adult eye occur within the first 6 months b. The sclera in an infant is approx half the thickness of the sclera in an adult c. A newborn has the same average IOP as an adult d. The lacrimal system is patent at birth but does not reach full development until 3-4 years

Answer 71

c. A newborn has the same average IOP as an adult The avg IOP of an infant is 10 mmHg and increases 1mmHg per year until the age of 5. The avg scleral thickness in an infant is 0.45mm vs 1.09 mm in an adult The lacrimal system is normally fully patent at birth, although 2-4% of neonates have an obstruction of the nasolacrimal system. It is not fully developed until 3-4 years of age

Question 72

Which of the following enzymes is inhibited by 1% trifluridine, prescribed for a patient with herpes simplex epi keratitis?

Answer 72

DNA polymerase 1% trifluridine (viroptic) is a topical ophthalmic antiviral medication that inhibits the replication of herpes simplex virus within corneal epi cells by inhibiting DNA polymerase. Recall that DNA polymerase is the enzyme responsible for extending the new DNA strand during replication

Question 73

What drug properties is the best at corneal penetration?

Answer 73

Hydrophilic and lipophilic properties NOTE: hardest is hydrophilic molecules

Question 74

A 31 year old pt presents w multiple molluscum contagiosum lesions bilaterally on his eyelids. What is the MOST appropriate test you should order to further eval this pt?

Answer 74

ELISA NOTE: molluscum contagiosum lesions are caused by DNA poxvirus. It is a self-limiting condition that typically resolves 2-3 months after onset. It most commonly occurs in children or in adults as a single or few lesions. Adults who preent w multiple lesions should be evaluated for an underlying immunosuppressive condition, including HIV. ELISA is the most appropriate test to order in cases of suspected HIV FTA-ABS and RPR test = syph CBC w diff = non specific usually to see if an infection, inflammation, bone marrow disorder, or autoimmune disease

Question 75

How does Fuch's heterochromic iridocyclitis affect bluer and browner eyes?

Answer 75

Bluer eyes become DARKER Browner eyes become LIGHTER NOTE: FHI is uni iridocyclitis that presents w minimal pain and redness & rarely presents with PAS/PS

Question 76

The terminal complex btwn RPE cells contain all of the cell junctions EXCEPT: a. Zonula adherens b. Hemidesmosomes c. Macula adherens d. Zonula occludens

Answer 76

b. Hemidesmosomes NOTE: terminal complex btwn RPE cells that forms the BRB is composed of ZO, ZA, & MA. Hemidesmosomes connect an epi layer w its underlying basement membrane

Question 77

A pt presents w Rx -2.00-2.00X150. Which line will appear MOST blurred on clock dial test when pt is uncorrected?

Answer 77

2-8 o'clock

Question 78

Decreased levels of the enzyme citrate synthase will MOST likely result in the INC production of all of the following EXCEPT: a. Acetoacetate b. Acetone c. Beta-hydroxybutyrate d. ATP

Answer 78

d. ATP Citrate synthase is responsible for converting acetyl CoA into citric acid, which is the 1st step in Kreb;s cycle. If citrate synthase is NO longer available, acetyl CoA is shuttled away from the Krebs cycle & is used to produce ketone bodies (acetone, acetoacetate, and beta-hydroxybutyrate). Recall that ketone bodies are primarily produced during starving conditions.

Question 79

How does the body compensate for blood acidity changes from hypoventilation? a. DEC excretion of HCO3- b. DEC excretion of H+ c. INC excretion of HCO3- d. INC excretion of H+

Answer 79

a. DEC excretion of HCO3-

Question 80

What infectious entity is MOST commonly implicated in the development of acute retinal necrosis syndrome (ARN)?

Answer 80

Varicella zoster NOTE: ARN is most commonly attributed to members of the herpes virus family, predominantly varicella zoster and herpes simplex.

Question 81

A serous retinal detachment is associated w all of the following EXCEPT: a. Posterior scleritis b. Proliferative vitreoretinopathy c. Optic pit d. Intraocular neoplasm

Answer 81

b. Proliferative vitreoretinopathy

Question 82

Which of the following oral NSAID is MOST appropriate in pts w peptic ulcer Dz? a. Naproxen b. Ibuprofen c. Celecoxib d. Indomethacin

Answer 82

c. Celecoxib Celecoxib is a selective COX2 inhibitor COX2 prevents production of inflammatory PG w minimal effects on PG produced physiologically. COX2 inhibitors are therefore MOST appropriate in pts w peptic ulcer Dz bc it will have minimal impact on the synthesis of PG that protect the gastric mucosa. The other choices exacerbate peptic ulcers

Question 83

INC water content in a traditional hydrogel contact lens results in which of the following? a. Better handling b. Improved VA c. DEC depositing d. Greater stability

Answer 83

a. Better handling INC water content in a traditional hydrogel CL results in better handling bc inc water leads to inc in CL thickness. DEC water content in a traditional hydrogel CL results in greater stability (a thinner CL will move less on eye), improved VA (due to better optics), and DEC deposits on the CL surface

Question 84

Deposits are more likely to be in which FDA classification of SCL?

Answer 84

Group 4: HIGH water content, ionic

Question 85

Which of the following are contraindications of oral CAIs such as acetazolamide (select 3)? a. Post op cataract care b. Systemic HTN c. Pregnancy d. Tachycardia e. Liver disease f. Severe COPD g. Cough

Answer 85

c. Pregnancy e. Liver disease f. Severe COPD Acetazolamide should be avoided in pts w severe COPD bc these pts may be unable to inc their alveolar ventilation enough to compensate for the acid-base alterations induced by the drug. Further, alkalinization of urine may result in INC levels of ammonia in the systemic circulation, contributing to the development of hepatic encephalopathy. Thus, acetazolamide is CI in pts w clinically sig liver disease. It is also CI during preg. Post op cat care & tachycardia are not CI; acetazolamide lowers BP & is therefore a benefit in pts w systemic HTN

Question 86

Which of the following statements regarding retinopathy of prematurity (ROP) are CORRECT? select 3 a. Screenings for ROP should be performed at the hospital after birth for all babies who weight less than 2000 grams b. Pts w ROP may present w a "dragged" appearance of the macula c. Unlike infants born at a normal birth weight, infants w ROP demonstrate an incomplete development of the macula at birth d. Incomplete development of the macula at birth e. INC O2 exposure immediately after birth leads to an INC risk of development ROP f. ROP may be assocaited w the development of high myopia in infants

Answer 86

b. Pts w ROP may present w a "dragged" appearance of the macula e. INC O2 exposure immediately after birth leads to an INC risk of development ROP f. ROP may be assocaited w the development of high myopia in infants Screenings for ROP are performed in infants who weight < 1500 grams at birth, as they have the higher risk for development of ROP. The development of the macula is incomplete at birth in all infants, not just those who develop ROP. The macula continues to mature through 4 years of age.

Question 87

Which entopic phenomenon should be MOST concerning to a clinician? a. Phsophenes b. Blue arcs of the retina c. Purkinje tree d. Moore's lightning streaks

Answer 87

d. Moore's lightning streaks Moore's lightning streaks are vertical flashes of light seen in the periphery of the visual field. They are associated w viterous syneresis and retinal distention (tugging on the retina) and can be a harbinger of retinal breaks or detachments. Purkinje tree is a normal phenomenon that involves the visualization of the retinal vasculature as moving light casts shadows on the retina Phosphenes are flashes of light that are a result of neural noise or mechanical (i.e. rubbing one's eyes) or electrical stimulation of the retina (almost NEVER a sign of peripheral retinal issues) Blue arcs of the retina originate from a light source and extend towards the physiological blind spot. Perceived when viewing a dim light in a dark room

Question 88

Which of the following serum lab results is Dx of acute pancreatitis?

Answer 88

Elevated lipase The pancreas is responsible for releasing enzymes into the intestine for digestion, including lipase and amylase. Pancreatitis results in a DEC in the release of lipase and amylase into the digestive tract causing an increase in blood serum levels.

Question 89

What does the blur point represent in a pt who is being tested for negative fusional vergence at 6pd?

Answer 89

Convergence-induced accommodation has decreased and the pt is no longer able to increase blur-induced accommodation to keep the target clear; the pt's hyperopia is under-corrected NOTE: blur point is not expected when testing NFV ranges at distance bc accomm should be fully relaxed. however, if a pt does report a blur point at far, the pts accomm was not fully relaxed at the beginning of the test, indicating too little plus (or too much minus) in the distance rx

Question 90

Which of the following characteristics of the corneal stroma contributes to corneal transparency? a. there is less cross-linking and less branching of collagen fibers in the posterior 2/3 of the cornea b. The anterior 1/3 of the stroma has a high degree of cross-linking btwn collagen fibers c. Glycosaminoglycans within the stroma repulse water to maintain corneal transparency d. Collagen lamellae within the stroma are uniformly spaced

Answer 90

d. Collagen lamellae within the stroma are uniformly spaced NOTE: uniform spacing of type 1 collagen lamellae is essential in order to maintain corneal transparency. Glycoaminoglycans attract water and help maintain the precis spacing of the collagen lamelle. The degree of cross-linking and branching of collagen fibers in the ant compared to the post stroma contributes to corneal rigidity and curvature more so than corneal transparency

Question 91

Which of the following statements regarding the conjunctiva is INCORRECT? a. The conj moves in conjunction w the eye bc the forniceal conj is attached to the fascia surrounding the EOM b. The marginal conj is continuous w the epi of the skin at the mucocutaneous junction of the lid c. The submucosa of the bulbar conj is loosely attached to Tenon's capsule until approx 3 mm from the cornea d. The submucosa of the tarsal conj is thin and loosely attached to the tarsal plate

Answer 91

d. The submucosa of the tarsal conj is thin and loosely attached to the tarsal plate FALSE The submucosa of the tarsal conj is THICKER compared to the marginal conj bc it contains the accessory lac glands. It is tightly linked tot he underlying tarsal plate of the upper eyelid. The remaining statements regarding the conj are correct.

Question 92

What is the gain of the VOR approximately?

Answer 92

1:1 VOR functions to keep eyes aligned w an object during head movement. The gain is the ratio of eye movement to head movement. Thus, the gain must be 1:1 (i.e. 5 degrees of eye movement for 5 degrees of head movement) in order to keep the eyes aligned on the image

Question 93

A 45 year old female presents w 2+ superior bulbar conj injection that stains w lissamine green and NaFl, small superior bulbar conj papillae, and superior superficial punctate keratitis OU. What is the MOST likely Dx?

Answer 93

Superior limbic keratoconjunctivitis

Question 94

Which of the following conditions is MOST likely to result in permanent loss of vision? a. Atopic keratoconjunctivitis b. Perennial allergic conjunctivitis c. Seasonal allergic conjunctivitis d. Vernal keratoconjunctivitis

Answer 94

a. Atopic keratoconjunctivitis Atopic keratoconjunctivitis may cause corneal epi erosions, corneal neo & opacification, conj scarring, & symblepharon formation, resulting in permanent DEC vision

Question 95

Oral propranolol should be prescribed w caution in pts w which of the following systemic conditions (select 3)? a. Insulin-dependent DM b. POAG c. COPD d. Bronchil asthma e. Cardiac arrhythmias

Answer 95

a. Insulin-dependent DM c. COPD d. Bronchil asthma NOTE: propranolol is a nonselective Beta-receptor antagonist. It has negligible effects on alpha receptors and muscarinic receptors. Inhibition of beta-2 in lungs leads to bronchoconstriction; thus, propranolol should be used w caution in pts w COPD and asthma. Propranolol may also result in hypoglycemia & should be prescribed w caution in pts w insulin-dependent DM. Selective Beta-1 receptor antagonists are safer alternatives to propranolol for pts w these systemic conditions.

Question 96

Which of the following oral medications may cause aplastic anemia (SELECT 3)? a. Acetazolamide b. Furosemide c. Chlorpheniramine d. Cephalexin e. Trimethoprim f. Chloramphenicol

Answer 96

a. Acetazolamide e. Trimethoprim f. Chloramphenicol (fatal + optic neuritis) Aplastic anemia is a fatal condition secondary to bone marrow suppression; it is characterized by insufficient production of new blood cells NOTE: methotrexate also causes

Question 97

Which of the following statements regarding the clinical properties of the topical ophthalmic combination agent brinzolamide/brimonidine is TRUE? a. the FDA-approved dosing frequency is BID b. This medication is the only combination agent for the Tx of elevated IOP that does NOT contain an adrenergic antagonist c. This medication should be avoided in pts w asthma or COPD d. This medication is less effective than either of its components used singly or in combination

Answer 97

b. This medication is the only combination agent for the Tx of elevated IOP that does NOT contain an adrenergic antagonist

Question 98

A lesion that impacts only the parvocellular pathway would have the MOST effect on what?

Answer 98

Ability to discern colors in isoluminant gratings NOTE: the magnocellular pathway processes and transmits the majority of high-frequency flickering stimuli, low spatial frequency stimuli, and stimuli that move at high velocities. Conversely, the parvocellular pathway processes and transmits the majority of wavelength-based discrimination (color vision) & high spatial frequency stimuli (VA). Isoluminant gratings are gratings that consist of diff wavelengths w the same luminance. If each grating had a diff luminance, the magnocellular pathway would be able to differentiate the wavelengths based on perceived brightness of the diff bars as determined by the photopic luminance function.

Question 99

Which of the following statements regarding metamers is INCORRECT? a. Metamer theory applies to dichromats but not trichromats b. They are visual stimuli that are physically diff but result is identical visual perception c. INC the intensity of the two metamers will change both metamers, , but they will still appear identical d. Adding light of the same wavelength and radiance to two metamers will change both metamers, but they will still appear identical

Answer 99

a. Metamer theory applies to dichromats but not trichromats Metamer theory is based on the principle of uvariance: the wavelength of a given light determines how many photons are absorbed by the visual system, but once the photon is absorbed, all info about wavelength is lost. the implication is that the visual system can be confused. we can create metamers by mixing diff wavelengths to make them appear identical. Grassman's law tell us that we can make certain changes to metamers and they will still appear identical. One of grassman's laws staes that adding light of the same wavelength and radiance to two metamers will result in an identical change in both metamers. Another of grassman's laws states that increasing the intensity of two metamers will result in an identical change in both metamers. Metamer theory applies to trichromates and dichromats.

Question 100

A clinician performs NPC testing on a pt who is wearing their habitual correction. Which of the following vergence eye movements made by the pt has the LEAST contribution in NPC testing? a. Proximal b. Accommodative c. Fusional d. Tonic

Answer 100

a. Proximal Its present but clinically negligible

Question 101

The PR dark current is characterized by all of the following EXCEPT? a. Resting membrane potential is more negative than other cells b. Higher outer segment membrane permeability to Na+ ions c. Net flow of cations into the outer segment and out of the inner segment d. High outer segment membrane permeability to Ca2+ ions

Answer 101

a. Resting membrane potential is more negative than other cells The PR dark current is characterized by net flow of cations into the outer segment and out of the inner segment. This is accomplished by the CNG (i.e. phototransduction) channel, which increases outer segment permeability to Na_ and Ca2_, resulting in a less (-) resting membrane potential

Question 102

Increased tension on the scleral spur PRIMARILY results in which of the following?

Answer 102

INC in corneoscleral outflow NOTE: scleral sput is the point of attachment for the ciliary muscle longitudinal fibers and the lamellae of the TM. Ciliary muscle contraction INC tension and pulls the scleral spur posteriorly, resulting in an increase in the size of the pores of the TM & an INC in corneoscleral outflow

Question 103

A 47 year old male presents w an iris OD that is sig lighter in color than the iris OS. You note stellate keratic precipitates, trace cells in the AC, and a sig posterior subcapsular cataract OD. His IOP are 32 mmHg OD and 16 mmHg OS. What is his Dx most likely?

Answer 103

Fuchs' Heterochromatic Iridocyclitis FHI is characterized by a chronic low grade anterior chamber inflammation that leads to the development of iris heterochromia, stellate keratic precipitates, PSC, and elevated IOP

Question 104

Pt presents w peripheral corneal ulcer and associated anterior necrotizing scleritis. What is the MOST likely cause of this pt's peripheral ulcerative keratitis?

Answer 104

Collagen vascular disease Peripheral ulcerative keratitis, particularly in combination w scleritis, carries a high risk of an underlying, often undiagnosed, collagen vascular disease or systemic vasculitis

Question 105

Topically administered ophthalmic cyclopentolate may cause systemic adverse effects in low birth weight infants. Which of the following is NOT a possible ADE? a. Inhibition of gastric secretion b. Hyperglycemia c. INC Heart reat d. Elevated BP

Answer 105

b. Hyperglycemia Trop alone does not produce sufficient mydriasis in premature infants.

Question 106

True or false. The topical form of Besifloxacin medication was derived from systemic formulations.

Answer 106

False!

Question 107

When is edge clearance the lowest?

Answer 107

The peripheral curve radius is steep in combination with the smallest width. In this case, the 10.4mm radius, in combo w 0.2mm width, would represent the lowest or least edge clearance design

Question 108

Which ophthalmic drugs do NOT provide rapid relief of ocular itching? a. Lodoxamide b. Emedastine c. Epinastine d. Olopatadine

Answer 108

a. Lodoxamide NOTE: lodoxamide is a mastc ell stabilizer that prevents mast cell degranulation and the release of allergic mediators (i.e. histamine). It is ineffective at treating acute ocular allergy symptoms bc it cannot reverse the effects of histamine that has already been released by degranulated mast cells. Emedastine is a selective H1 receptor antagonist that prevents histamine from binding to its receptors; this, it is indicated for hte rapid relief of ocular itching. Epinastine and olopatadine are dual acting mast cell stabilizer and antihistamines and are indicated for both immediate and long-term Tx of ocular allergies

Question 109

All of the following are CI to the admin of topical ophthalmic pilocarpine EXCEPT: a. Hx of RD b. Absolute presbyopia c. Uveitic glaucoma d. COPD

Answer 109

b. Absolute presbyopia

Question 110

All of the following topical ophthalmic medications are indicated for the Tx of fungal keratitis EXCEPT: a. Amphotericin B b. Natamycin c. Miconazole d. Trifluridine

Answer 110

d. Trifluridine

Question 111

Which of the following systemic medications is NOT associated w NAION? a. Sumatriptan b. Sildenafil c. Amiodarone d. Prednisone

Answer 111

v Prednisone has not been linked to NAION. The remaining are associated. Sumatriptan is selective serotonin agonist that is used in the Tx of migraines. Sildenafil is a PDE-5 inhibitor used in the Tx of ED. Amiodarone is indicated for tps w cardiac arrhythmias

Question 112

Which of the following 2 statements regarding the Developmental Test of Visual Motor Integration are CORRECT? (select 2) a. Partial credit may be given when the pt meets 2/3 criteria for a given response b. Pts are allowed to erase and correct their drawings c. The test should be stopped after a pt misses 3 consecutive examples d. The pt's drawings are graded based on specific criteria that involve measuring the angles and the length of the figures e. The pt is asked to trace drawings in pencil during the test.

Answer 112

c. The test should be stopped after a pt misses 3 consecutive examples d. The pt's drawings are graded based on specific criteria that involve measuring the angles and the length of the figures