CO Optical Devices & Low Vision Rehabilitation Flashcards

Low vision is generally defined as best-corrected visual acuity of:

Answer: 20/70 or worse in the better eye

Low vision is defined as best-corrected visual acuity of 20/70 or worse in the better eye that cannot be improved with standard optical correction.

Fresnel press-on prisms incorporated into a spectacle lens are primarily used to manage:

Answer: Diplopia caused by strabismus

Fresnel press-on prisms are used to neutralize diplopia by redirecting the visual axis in patients with strabismus, especially when deviation may change over time.

Which low vision device uses a strong convex lens resting on reading material to magnify near objects?

Answer: Stand magnifier

Stand magnifiers use a strong convex lens mounted at a fixed focal distance and rest directly on reading material to provide stable near magnification.

When prescribing base-out prism for a patient with esotropia and diplopia, the prism functions by:

Answer: Redirecting the visual axis nasally to align the diplopic images

Base-out prism redirects the visual axis nasally, compensating for esotropia and aligning the diplopic images to eliminate double vision.

Bioptic telescopes are primarily prescribed to:

Answer: Allow patients with low vision to meet driving visual acuity requirements

Bioptic telescopes are miniature telescopes mounted superiorly in spectacle lenses that allow patients with low vision to spot-check acuity for driving in states that permit bioptic driving.

According to Prentice's Rule, the prismatic effect in prism diopters equals:

Answer: Lens power in diopters multiplied by decentration in centimeters

Prentice's Rule states that prismatic effect (Δ) = lens power (D) × decentration (cm), essential for calculating induced prism from decentered lenses.