Lecture 7: prescribing for different refractive states NEAR

Question 1

What are the aims of prescribing for presbyopes?

Answer 1

*Give comfortable N5 at preferred working distance (need to establish exact wd)
*Give a useful range of clear vision: check if you can move reading material in by x cm from PWD before it blurs and move out 2x cm from PWD before it blurs.
*E.g., px PWD is 40 cm. moves material in by 15 cm before it blurs and out by 30 cm.

Question 2

When should you olny consider reducing or increasing power for near?

Answer 2

px complains they have to hold the material too close

Question 3

Why might the px not be happy if the positive power is increased too much?

Answer 3

-established relationship between accommodation and convergence is upset
-the range of distinct vision may be reduced to an unacceptable extent

Question 4

The higher the ADD…

Answer 4

the lower the range of clear vision

Question 5

What are the symptoms of nuclear sclerosis cataract?

Answer 5

second sight
-myopic shift

Question 6

When should you prescribe an ADD?

Answer 6

-reading difficulties
-first ADD of +0.75

Question 7

What tentative ADD can you prescribe based on age?

Answer 7

45 years : +1.00
50 years: +1.50
55 years: +2.00

Question 8

When might you need to prescribe a intermediate ADD?

Answer 8

when near ADD reaches +2.00