CO CO Optical Devices & Low Vision Rehabilitation 2

Question 1

Eccentric viewing training teaches patients with a central scotoma to:

Accepted Answer

Use an intact peripheral retinal area as the preferred retinal locus (PRL)

Answer

Eccentric viewing training helps patients with central scotoma develop a preferred retinal locus in intact peripheral retina as a functional substitute for the damaged fovea.

Question 2

Telescope magnification is calculated as the ratio of:

Accepted Answer

Eyepiece lens power to objective lens power

Answer

Telescope magnification equals the power of the eyepiece divided by the power of the objective lens (equivalently, focal length of the objective divided by focal length of the eyepiece).

Question 3

A patient with homonymous hemianopia may benefit from which optical device to improve awareness of the blind hemifield?

Accepted Answer

Sector prism or mirror placed on the hemianopic side

Answer

Sector prisms or Fresnel prisms placed on the hemianopic side of spectacles redirect images from the blind hemifield into the seeing field to alert the patient to objects.

Question 4

In orthoptic management of accommodative esotropia, bifocal or progressive addition lenses are prescribed to:

Accepted Answer

Reduce near accommodative demand and the associated convergence excess

Answer

Bifocal or progressive addition lenses reduce near accommodative demand in patients with accommodative esotropia, lessening the convergence excess that drives the near deviation.

Question 5

The magnification needed for a low vision patient is estimated by the formula:

Accepted Answer

Required magnification = desired VA denominator ÷ current VA denominator

Answer

The required magnification equals the desired visual acuity denominator divided by the current visual acuity denominator (e.g., 20/200 needing 20/40 requires 200/40 = 5× magnification).

(CO) Certified Orthoptist Practice Test

(CO) Certified Orthoptist Practice Test

CO CO Optical Devices & Low Vision Rehabilitation 2