Confrontation Visual Fields

Question 1

Purpose of confrontation visual fields and which optic nerve is evaluated?

Answer 1

To make a gross check of the patients peripheral field of vision. CN II is evaluated

Question 2

Temporal retinal fibers see the ___ visual field
Nasal retinal fibers see the ___ visual field
Superior retinal fibers see the ___ visual field
Inferior retinal fibers see the ___ visual field

Answer 2

Nasal
Temporal
Inferior
Superior

Question 3

Path of ON II after exiting the eye

Answer 3

OD:

• Temporal retina travels directly back to R side of brain.
• Nasal retina crosses over to left side.

OS:

• Temporal retina travels directly back to L side of brain.
• Nasal retina crosses over to the left side.

Nasal fibers cross at the chaiasm.

Question 4

Difference between optic nerves, optic chasm, optic tracts, and occipital cortex

Answer 4

1. Optic nerves- Right as the fibers exit the eye, before any split occurs.
2. Optic chiasm- Crossing over between nasal fibers to the opposite side of the brain
3. Optic tracts- OD temporal traveling with OS nasal on the right side of the brain. OS temporal traveling with OD nasal on the left side of the brain.
4. Occipital cortex- Where vision is processed I guess?

Question 5

Quadrantopsia

Answer 5

One fourth of the visual field gone

Question 6

Hemianopsia

Answer 6

One half of the visual field gone (superior, inferior, right or left)

Question 7

Homonymous

Answer 7

Both eyes involved, same side of visual field affected (Ex: both eyes missing R side of field)

Question 8

Scotoma

Answer 8

Isolated area of visual field loss. Not a whole quadrant, island of vision loss.

Question 9

Glaucoma

Answer 9

Intraocular pressure causing a degeneration of the optic nerve. In later stages, there is a shrinkage or constriction of the visual field.

Question 10

Lesion

Answer 10

A break in the conduction of the nerve impulse

Question 11

What are you checking for when doing:

Peripheral field finger counting?

Answer 11

Checking all 4 quadrants for quadrantopsias and hemianopsia.

Question 12

What are you checking for when doing:

Simultaneous finger counting

Answer 12

Parietal lobe extinction phenomenon. When a stimulus is presented only in the defective field, the stimulus is seen. However, when an additional stimulus is placed in the opposite hemifield simultaneously, the stimulus in the contralesional fired is not perceived.

Question 13

What are you checking for when doing:

Hemifield comparison

Answer 13

Checks for the relative defect between the two eyes.