Prism Implementation iQuiz

Which method of prism implementation in spectacles is used to correct vertical imbalance?

• Slab-off

• Ground-in

• Fresnel

• Prism by decentration

Which of the following is NOT a characteristics of Fresnel prism?

• Thin, light weight

• Fairly inexpensive

• Limited available prism power

• Can be easily applied in office

Which of the following visual function is negatively impacted by the Fresnel prism?

• visual acuity

• color perception

• depth perception

• visual field

For a pair of spectacles with +0.50 DS OD/OS, what is the approximately maximum amount of ground-in prism that can be prescribed?

• 10pd

• 20pd

• 30pd

• 40pd

What is the approximate maximum amount of prism correction that can be achieved with slab-off prism?

• 7Δ

• 8Δ

• 9Δ

• 10Δ

What type of prism can be implemented in a contact lens?

• base-in

• base-out

• base-up

• base-down

Your patient has a right hyperphoria at near and needs 2 vertical prism to see single at near. Which of the following is an appropriate method for implementing this prescription?

• Ground-in 2BU over right eye

• Ground-in 2BD over right eye

• Conventional slab off 2pd over right eye

• Reverse slab off 2pd over right eye

Your patient has a comitant, constant right esotropia of 16 prism diopters and needs 10 BO to achieve sensory fusion. How would you implement the prescription using ground-in prism?

• 10 BO OD, no prism OS

• 7 BO OD, 3 BO OS

• 5 BO OD, 5 BO OS

• no prism OD, 10 BO OS