ABO Low Vision & Rehabilitation 3

Question 1

Which condition is characterized by a ring scotoma that most severely affects mobility and orientation rather than fine reading tasks in early stages?

Accepted Answer

Retinitis pigmentosa

Answer

Retinitis pigmentosa causes progressive peripheral field loss (ring scotoma) that impairs mobility and night vision while central acuity for reading is preserved until late stages.

Question 2

The contrast sensitivity function (CSF) in low vision patients is clinically important because it

Accepted Answer

Often explains functional difficulty even when Snellen acuity appears relatively preserved

Answer

Patients can have near-normal Snellen acuity yet severely reduced contrast sensitivity, explaining difficulties with face recognition, mobility in low contrast environments, and reading low-contrast print.

Question 3

For a patient with hemianopia following a stroke, which non-optical rehabilitation strategy can most directly expand the usable visual field for reading?

Accepted Answer

Training compensatory saccadic eye movements toward the blind field side

Answer

Saccadic training (scanning therapy) teaches patients to make larger, more deliberate eye movements into the blind field, effectively increasing the functional reading field.

Question 4

A low vision specialist is evaluating an 8-year-old with albinism and acuity of 20/200. Which device would be most appropriate as an initial near aid for classroom reading?

Accepted Answer

A closed-circuit television (CCTV) system placed on the student's desk

Answer

A CCTV (video magnifier) allows the child to use both hands, adjust magnification as needed, and work at a comfortable posture, making it practical for sustained classroom use.

Question 5

What is the primary advantage of a head-mounted electronic magnification device (e.g., OrCam, eSight) over optical magnifiers for patients with moderate low vision?

Accepted Answer

They allow hands-free use, variable magnification, and often have additional features like text-to-speech

Answer

Head-mounted electronic devices offer hands-free operation, adjustable magnification across tasks, and supplemental features such as OCR/text-to-speech that optical aids cannot provide.

ABO - American Board of Optometry Practice Test

ABO - American Board of Optometry Practice Test

ABO Low Vision & Rehabilitation 3