Extra Questions for Module 10
          Evaluation of Rx
Each worksheet is different, because each one was originally written by a different person.  Use the directions at the beginning of each worksheet for that worksheet.

Refractive errors

What is the refractive error for each of the following Rs's.  Use SMA, SHA, CMA, CHA, H, M.
Note that we do not use simple hyperopia for a spherical Rx, so if you wrote that it is wrong.  Simple is used for an astigmatism.  If it is spherical it is myopia or hyperopia.  Not simple myopia or simple hyperopia.
 
 
1.  +3.50

2.  -1.00 -1.00 x180

3.  +0.50 -2.00 x030

4.  -1.00 +1.00 x080

5.  -1.00 +3.00 x110

6.  +8.75 -2.25 x005

7.  -16.75 -2.00 x179

8.  -16.75 +2.00 x005 

9.  -0.75 +1.00 x092

10.  -1.62 +1.75 x115

11.  +0.25 -0.50 x135

12.  pl -0.50 x058

13.  -4.25

14.  pl +3.75 x053

15.  +0.25 -0.50 x145

16.  +0.25 -0.25 x135

17.  +22.50 -3.50 x058

18.  -0.25 -0.50 x033

19.  +1.00 -2.00 x090

 1.  H

2.  CMA

3.  MA

4.  SMA

5.  MA

6.  CHA

7.  CMA

8.  CMA

9.  MA

10.  MA

11.  MA

12.  SMA

13.  M

14.  SHA

15.  MA

16.  SHA

17.  CHA

18.  CMA

19.  MA

Refractive Errors Study Sheet

1.  What are the two major causes of myopia?  Eye too long or the cornea/lens too much + power.

a.  How do we correct for myopia?  Minus lens power.
b.  What are the symptoms of myopia?  Distance out of focus, near in focus (at some particular distance).
c.  What is another term for myopia?  Nearsighted.  Why is it called that?  Because the person sees up close.
2.  What are the two major causes of hyperopia?  Eye too short or the cornea/lens not enough + power.  NOTE:  too much - power is NOT a correct answer.
a.  How do we correct for hyperopia?  Plus lens power.
b.  What are the symptoms of hyperopia?  Distance in focus, near out of focus, or not comfortable.
c.  What is another term for hyperopia?  Farsighted.  Why is it called that?  'Cause I said so.
3.  What is the cause of presbyopia?  Loss of accommodative ability in the lens/ciliary muscle system.
a.  How do we correct for it?  Plus lens power, or less minus power than the distance Rx.
b.  What are the symptoms of presbyopia?  Inability to focus on close material when the distance vision is clear.
4.  what do the following mean:
a.  OD  Right eye or right lens.
b.  OS  Left eye or left lens.
c.  OU  Both eyes or both lenses.
d.  Add  Plus power that must be added to the distance Rx.
5.  What refractive error is corrected by the following Rs's:
 
a.  -5.00 sph
b.  +5.00
c.  pl, Add +3.50
d.  +2.00 -1.00 x090
e.  pl -2.50 x120
f.  -2.00 -2.00 x135
g.  +1.00 -1.00 x045
h.  +1.00 -2.00 x115
myopia
hyperopia
presbyopia
compound hyperopic astigmatism
simple myopic astigmatism
compound myopic astigmatism
simple hyperopic astigmatism
mixed astigmatism
 
 

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