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4.3. A trial soft contact lens moves excessively with eyelid blinks. Which of the following would decrease lens movement?

a.flattening the base curve while maintaining the diameter

b.decreasing the diameter while maintaining the base curve

c.increasing the power of the contact lens

d.steepening the base curve while maintaining the diameter

e.flattening the base curve and decreasing the diameter

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4.4. You fit a patient who has –3.50 D of myopia with an RGP contact lens that is flatter than K. If the patient’s average K reading is 7.80 mm and you fit a lens with a base curve of 8.00 mm, what is the shape of the tear lens?

a.plano

b.teardrop

c.concave

d.convex

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4.5.For the patient in question 4.4, what power RGP lens should you order?

a.–3.50 D

b.–4.00 D

c.–2.00 D

d.–2.50 D

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4.6. You fit a toric soft contact lens on a patient with a refractive error of –2.50 D –1.50 × 175. The trial lens centers well, but the lens mark at the 6-o’clock position appears to rest at the 5-o’clock position when the lens is placed on the patient’s eye. What power contact lens should you order?

a.–2.50 D –1.50 × 175

b.–2.50 D –1.50 × 145

c.–2.50 D –1.50 × 55

d.–2.50 D –1.00 × 175

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Appendix 4.1