How should the prism be added to this prescription?
Prescription: OD -200 -100 X 180 5BU, OS -1.50 -.50 X 90

Question

Quizplus · Accepted Answer

The prism should be added to this prescription by placing 2.5 base up in the right and 2.5 base down in the left.
This is called split prism. It makes the lenses more equally thick or thin, distributes balance. The right eye in this case will have the prism BU and to counter that the left eye will need to have the balance prism base down.

How Should the Prism Be Added to This Prescription