Download VSII Final 2008-Smith section

Vision Science II
Opto 5221
April 25, 200
Final Examination
Multiple choice - mark the most appropriate answer on the computer scoring sheet. If you have
concerns over a given question, write you concerns on your test and turn it in with your answer
sheet. Be sure to put your name on the test and indicate on the top of the front page which
questions I should examine.
1. In comparison to a normal Gaussian distribution, the distribution of spherical-equivalent
refractive errors for a young adult US population __________.
a. is leptokurtic in shape
b. has more high hyperopes (e.g., larger than +6D) than predicted on the basis of
chance.
c. has more high myopes (e.g., larger than -6D) than predicted on the basis of chance.
d. a and c are correct
e. a, b, and c are correct
2. Which of the following statements concerning the refractive errors in newborn infants is NOT
correct?
a. The distribution of refractive errors is similar in shape to a random Gaussian
distribution.
b. In comparison to children 3-5 years of age, newborns exhibit a higher prevalence of
larger refractive errors.
c. Premature infant are generally more hyperopic than full-term infants.
d. The average refractive error is about +2.5 D of hyperopia.
e. The shape of the distribution of refractive errors is symmetric about the mean.
3. What is the expected the average spherical equivalent refractive error for a normal,
infant at about 18 months of age?
a. +2.25 D
b. +1.5 D
c. +0.5 D
d. plano
e. -0.5 D
4. In comparison to infants whose parents are both myopic, infants of emmetropic parents
_______.
a. are about 5 times less likely to develop myopia during the school years.
b. are just as likely to become myopic if they start school at the same age.
b. are more than 20 times less likely to develop myopia during the school years
c. are twice as likely to develop myopia before the school years
e. usually develop myopia at a younger age.
5. With respect to spherical equivalent refractive errors, at which of the following ages would
you expect to find the smallest variance in the population of “normal” individuals?
a. at birth (full-term infants)
b. 4 years
c. 25 years
d. 50 years
e. 75 years
6. Which of the following ocular changes results in the largest changes in total refracting
power during the first 3 years of life?
a. a decrease in the refractive index gradient in the crystalline lens
b. an increase in the anterior and posterior lens radii.
c. a decrease in the posterior corneal radius of curvature
d. an increase in anterior corneal radius of curvature.
e. an increase in anterior chamber depth.
7. What is the most common age for the onset of common axial myopia in the US population?
a. 18 months
b. 3-6 years
c. 8-10 years
d. 14-18 years
e. 20-25 years
8. Which of the following parts of the eye reach adult-like dimensions at the earliest age?
a. cornea
b. vitreous chamber depth
c. crystalline lens
d. anterior chamber depth
e. axial length
9. Myopia is almost always associated with an increase in axial length. However, at which of the
following ages is the incidence of myopia or relative myopic shifts in refractive error
likely to be due to factors other than axial length?
a. premature infants and individuals 14-18 years of age.
b. premature infants and individuals 65-80 years of age
c. full-term neonates and individuals 65-80 years of age
d. full-term neonates and individuals 40-60 years of age
e. full-term neonates and children 14-18 years old
10. Which of the following statements concerning the normal changes in astigmatism
that occur during life is NOT correct?
a. In a young Caucasian population, the prevalence of astigmatism decreases
between the ages of 6 months and 3 years.
b. The total refractive astigmatism observed at 6 months of age is highly
correlated with the amount of corneal astigmatism.
c. In a young Caucasian population, the prevalence of astigmatism is higher at 6
months than at 30 years of age.
d. Most recent studies report that infants typically show with-the-rule astigmatism.
e. None of the above. All the statements are correct.
11. With respect to the development of myopia, which of the following statements is NOT
correct?
a. In general, the earlier the onset of myopia, the faster the annual rate of progression.
b. In general, the earlier the onset of myopia, the higher the final degree of myopia.
c. For many individuals, myopic progression stops in late teenage years when axial
growth normally stops.
d. The annual rate of myopic progression in US children is typically about 0.4 to 0.6 D
per year.
e. None of the above. All the statements are correct.
12. Approximately how much does the eye normally increase in axial length during the first 3
years of age?
a. 0.5 mm
b. 1.5 mm
c. 5 mm
d. 8 mm
e. 12mm
13. For the average individual, which of the following ocular properties are most likely to show
systematic changes between 5 and 10 years of age?
a. axial length and corneal power
b. axial length and lens power
c. vitreous chamber depth and corneal power
d. corneal power and with-the-rule astigmatism
e. refractive error and lens power.
14. Which of the following predictive statements is NOT correct?
a. At 6 years of age, refractive error is probably our best clinical predictor for who will
become myopic.
b. Children who have hyperopic errors greater than +1.5 D at age 6 years will typically
stay hyperopic.
c. Children who have hyperopic error between +0.5 and +1.5 D at age 6 years will
typically become clinically emmetropic.
d. Children who have refractive errors less hyperopic/more myopic than +0.5 D at age 6
years will typically become myopic in the next 5-6 years.
e. None of the above. All the statements are correct.
15. After 40 years of age, the eye develops more ______________.
a. against-the-rule/less with-the-rule astigmatism because the vertical meridian of
the cornea flattens with age at a faster rate than the horizontal meridian.
b. with-the-rule/less against-the-rule astigmatism because the vertical meridian of
the cornea flattens with age at a faster rate than the horizontal meridian.
c. against-the-rule/less with-the-rule astigmatism because the horizontal meridian
of the cornea gets steeper with age at a faster rate than the vertical meridian.
d. with-the-rule/less against-the-rule astigmatism because the horizontal meridian
of the cornea flattens with age at a faster rate than the vertical meridian.
e. none of the above are correct
16. With respect to the interocular balance of refractive errors during early infancy (0-3 yrs),
which of the following statements is correct?
a. Only 1 out of every 100 infants will exhibit a detectable anisometropia.
b. Infants who exhibit more than 1 D of anisometropia during early infancy almost always
development myopia later in life.
c. If an infant is isometropic (i.e., no anisometropia) at 1 yr, there is only about a 1 out of
100 chance that the infant will ever develop a significant anisometropia (e.g., >1.0 D).
d. The overall prevalence of significant anisometropia (e.g., >1,0 D) is relatively constant
from birth to 3 years of age.
e. Infants who exhibit about 1-2 D of anisometropia typically retain the anisometropia
through puberty.
17. Based on experiments involving form deprivation myopia in laboratory animals, which of the
following statements is NOT correct?
a. Form deprivation increases the amount of dopamine in the retina.
b. Form deprivation myopia can be prevented by the topical application of the dopamine
agonist, apomorhine.
c. Haloperidol is a selective D2 dopamine receptor blocker that when applied to the eye
eliminates the protective effects of apomorphine.
d. Early gene expression in glucagon containing amacrine cells is influenced in a
complimentary way by hyperopic versus myopic defocus.
e. None of the above. All the statements are correct.
18. Which of the following substances has been implicated as a possible choroidal signal
messenger in the biochemical cascade that regulates eye growth?
a. ZENK
b. retinoic acid
c. acetylcholine
d. vasoactive intestinal peptide
e. matrix metalloproteinase
19. Which of the following changes does NOT take place in mammalian sclera during the
development of form-deprviation myopia?
a. There is a increase in proteoglycan synthesis.
b. Gelatinolytic enzymes increase the amount catabolic activity in the sclera.
c. There is an increase in amount of MMP-2 activity in the sclera.
d. The extensibility or creep rate of the sclera increases
e. The sclera gets thinner.
20. Pirenzepine is a __________________________.
a. relatively selective nicotinic, cholinergic receptor blocker that acts primarily at the M3
muscarinic receptor.
b. unselective muscarinic, cholindergic receptor blocker that acts equal on all muscarinic
receptors.
c. relatively selective muscarinic, cholinergic receptor blocker that acts primarily at the
M1 muscarinic receptor.
d. relatively selective muscarinic, cholinergic receptor blocker that produces a mild
cycloplegia via its actions on the M4 muscarinic receptor.
e. relatively selective muscarinic, cholinergic receptor blocker that produces mild pupil
dilation primarily via its actions on the M1 muscarinic receptor.
21. Which of the following manipulations have been shown to prevent the myopia produced by
monocular form-deprivation in laboratory animals?
a. surgically removing the primary visual cortex.
b. cutting the optic nerve of the deprived eye.
c. topically applied atropine.
d. surgically eliminating the primary sympathetic and parasympathetic inputs to the
deprived eye.
e. none of the above
22. Which of the following statements concerning the mechanisms that mediate visiondependent eye growth are NOT correct?
a. FDM is a graded phenomenon; the degree of axial myopia is dependent of the degree
of image degradation.
b. The way in which the mechanisms that mediate vision-dependent eye growth
integrate the effects visual experience over time normally reduces the likelihood that
the eye will become myopic.
c. Because the mechanisms that mediate vision dependent growth integrate visual
experience over time in a non-linear way, the use of “diopters-hours” to quantify the
amount of near work is probably not the optimal measure.
c. The performance properties of the emmetropization process are qualitatively similar
across many species.
e. None of the above
23. Which of the following statements concerning the pattern of peripheral refractive errors
along the horizontal meridian is NOT correct?
a. The degree of radial astigmatism increases with eccentricity.
b. Myopic eyes (i.e., foveal refractive error) typically exhibit less myopia / more
hyperopia in the periphery.
c. Hyperopic eyes (i.e., foveal refractive error) typically exhibit less hyperopia / more
myopia in the periphery.
d. Relative peripheral hyperopia is often observed in children 1-2 years before the onset
of central axial myopia.
e. None of the above.
24. Studies in animals and humans have shown that topically applied beta-blocker, timolol
______________.
a. can slow the progression of myopia without lowering IOP.
b. can reduce the IOP in humans but not in animals.
c. can slow the progression of form-deprivation myopia in birds but not in humans.
d. can reduce IOP in both humans and animals but it does not slow the progression of
myopia.
e. can eliminate accommodation in birds without reducing IOP.
25. Which of the following statements concerning treatment strategies for myopia is NOT
correct?
a. Recent studies have shown that progressive addition lenses are most effective in
reducing the progression rate of myopia in children with nearpoint exophoria and a
small lag of accommodation.
b. Undercorrection of myopes at distance actually accelerates the progression rate of
myopes.
c. Pirenzepine has been shown to slow the progression of juvenile onset myopia in a
dose dependent fashion.
d. There is little evidence that prescribing base-in prism for near work reduces the
progression of juvenile onset myopia.
e. none of the above; all of the statements are correct
26. Which of the following statements concerning the operational properties of the visiondependent mechanisms that regulate refractive development is NOT correct?
a. The nonlinear temporal integration properties of the emmetropization process
normally reduce the likelihood that the eye will become myopic.
b. The potential for a clear retinal image is essential for normal emmetropization.
c. In order to produce axial myopia, the eye only has to experience form deprivation for
approximately half the daily light cycle.
d. The performance properties of the emmetropization process are qualitatively similar
across many species.
e. Vision-dependent mechanisms are probably active well into early adult life.
27. Which of the following statements concerning the operational properties of the visiondependent mechanisms that regulate refractive development is correct?
a. Peripheral vision does not normally influence foveal refractive development.
b. Early in life, a functioning fovea is essential for the recovery from vision-induced
refractive errors.
c. Visual signals from the fovea are essential for the phenomenon of form deprivation
myopia.
d. In both chickens and primates, form depriving half of the retina produces axial
elongation and myopia in the deprived part of the eye.
e. None of the above.
28. Which of the following statements concerning the effects of visual experience on
emmetropization is NOT correct?
a. Although LAISK procedures can correct the optical errors associated with myopia,
these surgical procedures do not reduce the extra risk for retinal detachment
associated with high degrees of myopia.
b. Eyes with myopia greater than about -6.00 are about 2 times more likely to develop
primary open-angle glaucoma than emmetropic eyes.
c. Viewing conditions that have been shown to produce axial myopic growth in young
animals first produce a decrease in the thickness of the choroid.
d. Form deprivation myopia can be prevented by the topical application of transforming
growth factor beta in chickens.
e. None of the above
29. Which of the following changes is NOT thought to contribute to the slow refractive error shift
that occurs between the ages 40 and 65 years?
a. an increase in anterior chamber depth
b. a decrease in vitreous chamber
c. the onset of presbyopia
d. an increase in the radius of curvature of the anterior and posterior lens surfaces.
e. an increase in the refractive index of the lens cortex.
30. Which of the following statements concerning the anti-myopia effects of muscarinic
cholinergic blocking agents is correct?
a. Atropine can reduce the progression of juvenile onset only if the concentration is high
enough to produce complete cycloplegia.
b. Although the duration of treatment required to slow myopic progression is not known,
it is likely that to maintain therapeutic effects, anti-myopia agents like atropine must
administered at least throughout the teenage years.
c. Pirenzepine is much stronger than atropine and only has to be administered once a
week to prevent myopic progression in juveniles.
d. Pirenzepine reduces axial elongation rates by decreasing intraocular pressure.
e. None of the above.