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Transcript
1. What is the average age of onset for juvenile onset myopia in Caucasian children in the
United States?
a. 3-4 years of age
b. 5-6 years of age
c. 8-10 years of age
d. 12-14 years of age
e. 16-20 years of age
2. In comparison to normal full-term infants, premature infants that are born before 32 weeks of
age and/or weigh less that 1500 gram __________.
a. exhibit longer axial lengths and are more myopic
b. have steeper crystalline lenses and are more myopic
c. have flatter corneas and are more hyperopic
d. have steeper corneas and are more myopic
e. none of the above are correct
3. What is the expected the average spherical equivalent refractive error for a normal
infant at birth?
a. +2.25 D
b. +1.5 D
c. +0.5 D
d. plano
e. -0.5 D
4. For a population of young adults, which of the following statements is most correct?
a. The distribution of corneal powers conforms to a normal Gaussian distribution.
b. Anterior chamber depth is randomly distributed across the population.
c. Lens power is distributed in a leptokurtic fashion.
d. a and b are correct
e. all of the above are correct.
5. Which of the following ocular changes results in the largest changes in total refracting
power during the first 3 years of life?
a. a relative increase in the refractive index of the crystalline lens core.
b. an increase in anterior corneal radius of curvature.
c. a decrease in the posterior corneal radius of curvature.
d. a decrease in the refractive index gradient in the crystalline lens.
6. 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 fewer 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
7. 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
8. Which of the following statements concerning the predictability of refractive errors in
young U.S. children is correct?
a. If a 5-year-old is a +1.50 D hyperope, it is very unlikely that they will develop
juvenile onset myopia.
b. If a 5-year-old is a +0.75 D hyperope, it is very likely that they will remain
clinically emmetropic at least until early adulthood.
c. If a 5-year-old is a -0.50 D myope, it is very likely that they will be myopic in
their early teenage years.
d. a and b are correct
e. all of the above are correct.
9. Which of the following statements concerning the prevalence of anisometropia during early
infancy (0-3 years) is correct?
a. Anisometropias of about 1-2 D are frequently transient during early development and
not very predictive of the balance of refractive errors later in life.
b. About 1 out of every 100 infants will exhibit a detectable anisometropia.
c. If an infant is isometropic (i.e., no anisometropia) at 1 year of age, 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 prevalence of significant anisometropia (e.g., >1,0 D) is higher a 3 years of age
than at birth.
e. None of the above.
10. For the average individual, which of the following ocular properties change the most
between 5 and 10 years of age?
a. lens power and axial length
b. corneal power and axial length
c. refractive error and axial length
d. vitreous chamber depth and corneal power
e. corneal power and lens power
11. Which of the following statements concerning the role of accommodation in emmetropization
and the development of refractive errors is correct?
a. The fact that bifocals slow the progression of myopia demonstrates that
accommodation plays a key role in the genesis of myopia.
b. Accommodation has an indirect effect on refractive development via its influence on
the eye’s retinal image quality.
c. Studies in monkeys have shown that prolonged accommodation during near work
produces axial myopia.
d. The fact that base-in prisms reduce myopic progression in esophoric juveniles
indicates that chronic over convergence promotes myopia.
e. A and B are correct.
12. Which of the following structures/pathways plays a role in the development of formdeprivation myopia?
a. the visual cortex.
b. the sympathetic input to the eye
c. the parasympathetic input to the eye
d. changes in choroidal thickness
e. none of the above
13. At which of the following ages is a myopic shift most likely due to changes in the crystalline
lens?
a. premature infants
b. juveniles 12-18 years of age.
c. individuals 65-80 years of age
d. individual 40 to 65 years of age
e. none of the above.
14. 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.
15. Which of the following statements concerning the implications of lens-rearing experiments in
laboratory animals on the phenomenon of emmetropization is NOT correct?
a. Emmetropization comes about primarily as a result of vision-dependent control over
lens thickness and lens power.
b. The eye uses visual feedback associated with the eye’s effective refractive status to
guide ocular growth toward emmetropia.
c. Brief daily periods of unrestricted vision have a stronger effect on eye growth in young
animals than much longer periods of either form deprivation or hyperopic defocus.
d. The emmetropization process has a limited operating range and refractive errors that
fall outside this range produce unpredictable growth.
e. None of the above
16. Which of the following statements concerning the normal changes in astigmatism
that occur during life is correct?
a. In a young Caucasian population, the prevalence of astigmatism increases
between the ages of 6 months and 3 years.
b. The total refractive astigmatism observed at 6 months of age is primarily due a
tilting of the crystalline lens with respect to the visual axis.
c. Infants typically show with-the-rule astigmatism.
d. a and c are correct
e. All of the above are correct.
17. With respect to the development of myopia, which of the following statements is NOT
correct?
a. Between the ages of 30 and 40 years, late onset myopia is most likely due to an
effective increase in corneal power.
b. For many individuals, myopic progression stops in late teenage years when axial
growth normally stops.
c. In general, the earlier the onset of myopia, the higher the final degree of myopia.
d. Children of two myopic parents are about 6 times more likely to become myopic than
children of non-myopic parents.
e. None of the above
18. Which of the following statements concerning the operational properties of the visiondependent mechanisms that regulate refractive development is correct?
a. Early in life, a functioning fovea is essential for the recovery from vision-induced
refractive errors.
b. Peripheral vision can mediate emmetropization.
c. Visual signals from the fovea are essential for the phenomenon of lens compensation.
d. Peripheral image degradation will not alter the pattern of peripherally refractive errors.
e. None of the above.
19. 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. Clinical studies have suggested that in young emmetropic adults relative peripheral
hyperopia is a risk factor for adult onset myopia.
e. None of the above.
20. Which of the following statements concerning treatment strategies for myopia is NOT
correct?
a. Recent studies have shown that undercorrecting myopic eyes for distance actually
accelerates the progression rate of myopia.
b. Topically applied anti-glaucoma drugs that reduce intraocular pressure do not prevent
or slow down the progression of myopia.
c. Pirenzepine is a relatively selective cholinergic muscarinic antagonist that has been
shown to slow the progression of juvenile onset myopia in a dose dependent fashion.
d. There is little evidence that prescribing progressive addition lenses reduces the
progression of juvenile onset myopia in esophoric children.
e. none of the above; all of the statements are correct
21. 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. The performance properties of the emmetropization process are qualitatively similar
across many species.
d. Vision-dependent mechanisms are probably active well into early adult life.
e. None of the above. All the statements are correct.
22. In the scleras of primate eyes, which of the following changes take place in response to a
myopiagenic stimulus like form deprivation?
a. The rate of proteoglycan synthesis is reduced in the posterior pole.
b. There is a decrease in production of matrix metalloproteinases that act as gelatinolytic
enzymes
c. The scleral tissue from the posterior pole becomes less able to resist stretching in
response to physical forces.
d. a and c are correct.
e. all of the above are correct.
23. Which of the following statements concerning the shape of emmetropic eyes of young adults
is correct?
a. Corneal power is usually negatively correlated with crystalline lens power.
b. Corneal power is usually positively correlated with axial length.
c. Crystalline lens power is usually negatively correlated with axial length.
d. There is a high negative correlation between total power and axial length.
e. Crystalline lens power is usually negatively correlated with corneal power.
24. Emmetropization is typically complete by _____________.
a. 1 month of age
b. 9 months of age
c. 18 months of age
d. 6 years of age
e. 16 years of age
25. During the first 3 years of life the power of crystalline lens decreases by approximately
____________.
a. 2-4 D
b. 5-8 D
c. 12-15 D
d. 18-22 D
e. 25-30 D
26. 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. a decrease in vitreous chamber
b. a decrease in lens thickness
c. the onset of presbyopia
d. an increase in the refractive index of the lens cortex.
e. None of the above are correct
27. Which of the following statements concerning the effects of visual experience on
emmetropization is NOT correct?
a. Topically applied atropine slows the progression of myopia by reducing the ability of
the eye to accommodate.
b. Form deprivation myopia can be prevented by the topical application of the dopamine
agonist apomorhine.
c. Providing the fovea with clear vision while at the same time producing form
deprivation in the periphery typically causes the eye to become myopic.
d. 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.
e. Viewing conditions that have been shown to produce hyperopic growth in young
animals can also produce an increase in the thickness of the choroids.