Test 1

Question 1

Which of the following columns in the OD histogram is driven equally by input from the right and left eyes? What about the other columns

Answer 1

1- Contra eye 
2-Both, but not equal
3- Both, but not equal 
4- Equal input 
5- both but not equal 
6- both but not equal
7- ipsi

Question 2

Co2 can be transported from tissues to the lungs through which methods

Answer 2

Bicarb 95%
Bound to hemoglobin as carbaminohemoglobin 5%
dissolved in blood plasma 5%

Question 3

Most common cause of posterior uveitis

Answer 3

Toxoplasmosis
-Most often congenital via transplacental transmission. Could also be acquired by inhaling a parasite in cat feces or by eating undercooked meat.

Question 4

Medication prescribed for Tb that is most likely to cause retrobulbar Optic neuritis

Answer 4

Ethambutol

Most often reversible, but may take months.

Question 5

image jump is based on what

Answer 5

Add power and distance from the top of the segment to the near OC

Question 6

scotopic system

Answer 6

Greater sensitivity for visual stimuli (more spatial summation) but poor visual acuity due to larger pixels for spatial summation.

Spatial summation means that all visual input within a given space pixel is summed together by the visual cortex.

Question 7

Thimerosal is the preservative in

Answer 7

Trifluridine

Question 8

Which preservative is prescribed to chelate calcium in patients with band keratopathy

Answer 8

EDTA

Question 9

Bucket 2 of pharm

Answer 9

Anti-cholinergic
1st gen antihisamines (PHEN)
Anti psychotics (Phenothiazine)
Antidepressants (TCA, MAOIs)

Question 10

Slab off

Answer 10

Add base up to the more minus lens.

Question 11

Most common site of metastases for a choroidal, conj, or iris melanoma

Answer 11

Liver

Question 12

Which corneal stromal dystrophies are related to a mutation in the TGFB1 gene?

Answer 12

Granular, lattice, avellino

Question 13

Min blank size formula

Answer 13

M = ED + 2d + 2mm

d= decentration per lens
Frame pd - pt pd / 2

Question 14

VOR

Answer 14

Obtains image on the fovea during short head movements

Question 15

Tritanopia

Answer 15

Missing cyanolabe

Question 16

Protanopia

Answer 16

Missing erythrolabe

Question 17

Deuteranopia

Answer 17

Missing chlorolabe pigment

Question 18

There are no __ cones or rods within the central one degree of the foveola

Answer 18

Blue

Question 19

Risk factors for bulls eye maculopathy

Answer 19

Treatment for 5+ years 
Liver disease
Kidney disease 
60+ years old 
High body fat 
Concomitant retinal disease 
Dosage 5+ mg/kg/day based on real body weight

Question 20

Distortion

Answer 20

Different magnitudes of magnification for different object points away from the optical axis.

Question 21

angle of anomaly equals what in HRC

Answer 21

Angle of anomaly = objective deviation

Question 22

angle of anomaly equals what in unharmonious ARC

Answer 22

Greater than zero, but less than the objective deviation.

Question 23

angle of anomaly equals what in paradoxical ARC

Answer 23

angle of anomaly is greater than the objective angle of deviation

Question 24

3 examples of granulomatous inflammation

Answer 24

Sarcoid
TB
syphilis

Question 25

Examples of extrinsic and intrinsic evaporative dry eye disease

Answer 25

Extrinsic- independent of lid pathology. Vitamin A deficiency, preservatives, CL wear. Intrinsic- due to lid pathology. MGD, proptosis, decreased blink rate.

Question 26

Which drug can cause secondary angle closure by causing choroidal swelling

Answer 26

Topiramate/Topamax | Moves iris forward --> angles narrows.

Question 27

Type of herpes simplex stromal keratitis with direct invasion of the virus into the K stroma? What is IK, disci form, and dendritic

Answer 27

Necrotizing- rare. Severe inflammation and necrosis --> thinning and perforation.; IK is due to an antigen-antibody complement cascade against a virus or viral antigen. Disciform keratitis is due to an immune response in the K endothelial cells. Poor pumping --> edema Dendritic is most common

Question 28

Molluscum contagiosa - What is it - Demographics

Answer 28

DNA pox virus Single or multiple waxy nodules, umbilicate. Immunocomp (HIV) or children

Question 29

Latent nystagmus

Answer 29

Pathological nystagmus when one eye is occluded. Associated with essential infantile esotropia and amblyopia.

Question 30

Accommodation reaches adult levels by

Answer 30

3 months

Question 31

accommodation reaches adult levels when

Answer 31

3 months

Question 32

Abbe values of Crown glass, CR39, polycarbonate, trivex. | What does abbe value mean?

Answer 32

Want a high abbe value= less chromatic aberrations. 58 58 poly 30 trivex 44

Question 33

Define entrance pupil, exit pupil, aperture stop, field stop.

Answer 33

Entrance pupil- Image of the aperture stop formed by all the lenses in FRONT of it. Exit pupil- the image of the aperture stop formed by all the lenses BEHIND it. Aperture stop- physical entity that limits the amount of LIGHT entering the system Field stop- physical entity that limits the SIZE of the object that can be viewed by the system.

Question 34

Which vitamins can lead to toxicity

Answer 34

Fat soluble vitamins stored in the body | ADEK

Question 35

Which water soluble vitamin aids in the synthesis of purine and pyrimidines

Answer 35

Folic acid | Deficiency causes impaired DNA and spina bifida.

Question 36

What parts of visual pathway does the anterior choroidal supply

Answer 36

Optic tract, LGN, optic radiations.

Question 37

Which 2 arteries supply the primary visual cortex

Answer 37

Posterior cerebral, middle cerebral.

Question 38

What does each of the follow color vision tests detect 1. Ishihara 2. Nagel anomaloscope 3. D 15 4. HRR

Answer 38

1. Ishihara: red green 2. Nagel anomaloscope: Can distinguish between anomalous trichromat and dichromat. 3. D 15: red green and blue yellow 4. HRR: red green and blue yellow

Question 39

Which 5 drugs can cause Whorl keratopathy

Answer 39

``` Amiodarone Indomethacin Hydroxychloroquin Chloroquine Tamoxifen ```

Question 40

Is silicone more or less permeable to oxygen than water

Answer 40

More. | Which is why increasing water content in siHy lenses causes decreased oxygen transmission.

Question 41

Average amp of accommodation formula

Answer 41

18.5 - 1/3(age)

Question 42

Which molecule is found at 40x higher concentration in the vitreous compared to the blood

Answer 42

Vitamin C

Question 43

systemic diseases associated with KCN

Answer 43

T-DOME !! ``` Turner syndrome Down syndrome Osteogenesis imperfecta Marfan syndrome Ehlers-Danlos ```

Question 44

Thickness of cornea in the center | Thickest and thinnest points of the choroid, sclera, and retina.

Answer 44

Choroid: Thickest at posterior pole 0.2mm Thinnest at ora serrata 0.1mm Sclera: Thickest at 1mm Thinnest at 0.3mm at reti insertions Retina: Thickest in the papilomacular bundle: 0.23mm Thinnest at fovea: 0.1mm Cornea is 0.52-0.55mm

Question 45

Parinaud oculoglandular sydrome

Answer 45

Eye problem similar to conjunctivitis. | Affects swollen lymph nodes and fever

Question 46

What do these stand for: VRDL RPR FTAA

Answer 46

VRDL: Venereal disease research laboratory RPR: Rapid plasma reagent card test FTAA: Fluorescent treponema antibody absorption

Question 47

4 types of bacteria than can penetrate an intact cornea

Answer 47

Canadian national hockey team: Corynebacterium dipltheriae, Neisseria gonorrhoeae, haemophilus, listeria

Question 48

What corneal finding is characteristic of EKC

Answer 48

serotype 8 symptoms 8 days after exposure SEIs 8 days after that. No longer contagious.

Question 49

4 ways to dx syphilis

Answer 49

FTA- ABS MHA- TP Dark field microscopy Enzyme immunoassay

Question 50

Internal hordeola is most commonly caused by

Answer 50

S. Aureus

Question 51

Staph epidermis is the most common cause of

Answer 51

Acute postoperative endophthalmitis

Question 52

Strep pneumonia may cause what 2 infections

Answer 52

Pediatric bacterial conjunctivitis | K ulcers

Question 53

When an ophthalmic topical drug contacts the tear film, the pH of the tears alters the drug to which of the following

Answer 53

Non0Ionized. The pH of the tears is 7.54. When drugs contact the tear film, the tears alter the drug into a non ionized form (hydrophobic) which promotes absorption across the hydrophobic corneal epi and endothelial. Ionized/hydrophillic drugs are less likely to be absorbed.

Question 54

What does each pathway do Medial lemniscus Tectospinal Trigeminothalamic Spinothalamic

Answer 54

Medial lemniscus- touch, pressure, vibration from the body. Tectospinal- reflexive head movements in response to visual stimuli. Trigeminothalamic- pain and temp from the face. Spinothalamic- pain and temp from the body.

Question 55

``` Define Sensitivity Specificity Positive predictive value Negative predictive value ```

Answer 55

Sensitivity- Ability of a test to detect a patient has the disease. Good to be sensitive. Specificity- Ability of a test to detect a patient doesn't have the disease. Positive predictive value- Probability that the patient has the disease if the test is positive. Negative predictive value- Probability that the patient doesn't have the disease if the test is negative.

Question 56

``` What are these lasers used for: Argon Excimer Nd: YAG Helium neon ```

Answer 56

Argon- PRP, focal laser tx for ME Excimer- LASIK, PRK Nd: YAG- PCO, SLT, LPIs Helium neon- illuminate the retina to view the fundus

Question 57

How do photoreceptors collect photons/how does color vision work

Answer 57

A wavelength of a photon determines the probability that the photon is absorbed by a photoreceptor. Based on the principle of univariance- once the photon is absorbed, all information regarding the wavelength of the photon is lost. A single photoreceptor cannot discriminate color. Color vision is based on the relative responses of different photoreceptors based on the number of photons each absorbed.