Optics - Contact Lenses

Question 1

How do you increase Sagital depth?

Answer 1

1. Decrease BC (remember BC has an inverse relationship)
2. Increase Diameter
   Increasing sagital depth increases suction and will get a tighter fit

Question 2

For Soft Toric CL how to do change the axis when the 6:00 mark has shifted left or right?

Answer 2

Pneumonic: LARS “left add, right subtract” Each clock hour is 30 degrees

Question 3

How do you calculate the piggy back lens needed for myopes and hype ropes?

Answer 3

Myopes is 1 x refractive error ; Hyperopes is 1.5 X the refractive error.